Fair Value Measurements - Fair Vaue Measurement (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Assets:
Derivatives	$ 239	$ 213
Separate Account Asset	98,579	90,282
Liabilities:
Derivatives	268	299
Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	20,134	20,839
Cash, Cash Equivalents, and Short-term Investments	1,375	1,061
Separate Account Asset	98,579	90,282
Total assets, fair value	120,393	112,460
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	287	308
Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	307	221
Cash, Cash Equivalents, and Short-term Investments	1,356	1,061
Separate Account Asset	92,849	84,329
Total assets, fair value	94,522	85,628
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	10	0
Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	18,152	18,981
Cash, Cash Equivalents, and Short-term Investments	0	0
Separate Account Asset	5,390	5,605
Total assets, fair value	23,781	24,793
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	258	299
Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	1,675	1,637
Cash, Cash Equivalents, and Short-term Investments	19	0
Separate Account Asset	340	348
Total assets, fair value	2,090	2,039
Liabilities:
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19	9
U.S. Treasuries \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	378	275
U.S. Treasuries \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	307	221
U.S. Treasuries \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	71	54
U.S. Treasuries \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
U.S. Government agencies and authorities \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	27	30
U.S. Government agencies and authorities \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
U.S. Government agencies and authorities \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	27	30
U.S. Government agencies and authorities \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
State, municipalities and political subdivisions \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	409	554
State, municipalities and political subdivisions \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
State, municipalities and political subdivisions \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	409	554
State, municipalities and political subdivisions \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
U.S. corporate public securities \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	5,249	5,605
U.S. corporate public securities \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
U.S. corporate public securities \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	5,202	5,592
U.S. corporate public securities \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	47	13
U.S. corporate private securities \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	3,799	3,636
U.S. corporate private securities \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
U.S. corporate private securities \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	2,628	2,451
U.S. corporate private securities \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	1,171	1,185
Foreign corporate public securities and foreign governments \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	1,868	2,022
Foreign corporate public securities and foreign governments \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
Foreign corporate public securities and foreign governments \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	1,820	2,022
Foreign corporate public securities and foreign governments \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	48	0
Foreign corporate private securities \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	2,029	2,299
Foreign corporate private securities \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
Foreign corporate private securities \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	1,688	1,945
Foreign corporate private securities \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	341	354
Residential mortgage-backed securities \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	2,525	2,532
Residential mortgage-backed securities \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
Residential mortgage-backed securities \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	2,471	2,484
Residential mortgage-backed securities \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	54	48
Commercial mortgage-backed securities \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	2,111	2,358
Commercial mortgage-backed securities \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
Commercial mortgage-backed securities \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	2,111	2,358
Commercial mortgage-backed securities \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
Asset-backed Securities [Member] \| Assets measured on recurring basis
Assets:
Fixed maturities including securities pledged, Fair Value	1,739	1,528
Asset-backed Securities [Member] \| Assets measured on recurring basis \| Level 1
Assets:
Fixed maturities including securities pledged, Fair Value	0	0
Asset-backed Securities [Member] \| Assets measured on recurring basis \| Level 2
Assets:
Fixed maturities including securities pledged, Fair Value	1,725	1,491
Asset-backed Securities [Member] \| Assets measured on recurring basis \| Level 3
Assets:
Fixed maturities including securities pledged, Fair Value	14	37
Equity Securities [Member] \| Assets measured on recurring basis
Assets:
Equity Securities, FV-NI	66	65
Equity Securities [Member] \| Assets measured on recurring basis \| Level 1
Assets:
Equity Securities, FV-NI	10	11
Equity Securities [Member] \| Assets measured on recurring basis \| Level 2
Assets:
Equity Securities, FV-NI	0	0
Equity Securities [Member] \| Assets measured on recurring basis \| Level 3
Assets:
Equity Securities, FV-NI	56	54
Stabilizer and MCGs \| Assets measured on recurring basis
Liabilities:
Guaranteed benefit derivatives	19	9
Stabilizer and MCGs \| Assets measured on recurring basis \| Level 1
Liabilities:
Guaranteed benefit derivatives	0	0
Stabilizer and MCGs \| Assets measured on recurring basis \| Level 2
Liabilities:
Guaranteed benefit derivatives	0	0
Stabilizer and MCGs \| Assets measured on recurring basis \| Level 3
Liabilities:
Guaranteed benefit derivatives	19	9
Interest Rate Contract [Member] \| Assets measured on recurring basis
Assets:
Derivatives	201	186
Liabilities:
Derivatives	266	290
Interest Rate Contract [Member] \| Assets measured on recurring basis \| Level 1
Assets:
Derivatives	0	6
Liabilities:
Derivatives	10	0
Interest Rate Contract [Member] \| Assets measured on recurring basis \| Level 2
Assets:
Derivatives	201	180
Liabilities:
Derivatives	256	290
Interest Rate Contract [Member] \| Assets measured on recurring basis \| Level 3
Assets:
Derivatives	0	0
Liabilities:
Derivatives	0	0
Foreign Exchange Contract [Member] \| Assets measured on recurring basis
Assets:
Derivatives	38	27
Liabilities:
Derivatives	2	8
Foreign Exchange Contract [Member] \| Assets measured on recurring basis \| Level 1
Assets:
Derivatives	0	0
Liabilities:
Derivatives	0	0
Foreign Exchange Contract [Member] \| Assets measured on recurring basis \| Level 2
Assets:
Derivatives	38	27
Liabilities:
Derivatives	2	8
Foreign Exchange Contract [Member] \| Assets measured on recurring basis \| Level 3
Assets:
Derivatives	0	0
Liabilities:
Derivatives	$ 0	0
Credit Default Swap [Member] \| Assets measured on recurring basis
Liabilities:
Derivatives		1
Credit Default Swap [Member] \| Assets measured on recurring basis \| Level 1
Liabilities:
Derivatives		0
Credit Default Swap [Member] \| Assets measured on recurring basis \| Level 2
Liabilities:
Derivatives		1
Credit Default Swap [Member] \| Assets measured on recurring basis \| Level 3
Liabilities:
Derivatives		$ 0

VOYA RETIREMENT INSURANCE & ANNUITY Co 10-K