Derivatives and Hedging Activities - Schedule of Customer Related Derivative Positions (Details) $ in Thousands	Mar. 31, 2026 USD ($) derivative	Dec. 31, 2025 USD ($) derivative
Receive fixed, pay variable
Derivatives and Hedging Activities
Total	$ 3,500,284	$ 3,505,840
Pay fixed, receive variable
Derivatives and Hedging Activities
Total	3,504,381	3,505,840
Risk participation-out agreements
Derivatives and Hedging Activities
Total	681,207	670,834
Risk participation-in agreements
Derivatives and Hedging Activities
Total	147,069	153,185
Foreign exchange contracts \| Buys foreign currency, sells U.S. currency
Derivatives and Hedging Activities
Total	2,965	2,785
Foreign exchange contracts \| Sells foreign currency, buys U.S. currency
Derivatives and Hedging Activities
Total	$ 2,978	$ 2,800
Derivatives not designed as hedging instruments \| Receive fixed, pay variable
Derivatives and Hedging Activities
Number of Positions \| derivative	304	308
Notional Amount Maturing, Less than 1 year	$ 348,919	$ 280,333
Notional Amount Maturing, Less than 2 years	332,118	427,625
Notional Amount Maturing, Less than 3 years	616,891	368,548
Notional Amount Maturing, Less than 4 years	460,263	699,796
Notional Amount Maturing, Thereafter	1,742,093	1,729,538
Total	3,500,284	3,505,840
Fair Value	$ 70,480	$ 58,840
Derivatives not designed as hedging instruments \| Pay fixed, receive variable
Derivatives and Hedging Activities
Number of Positions \| derivative	305	308
Notional Amount Maturing, Less than 1 year	$ 348,919	$ 280,333
Notional Amount Maturing, Less than 2 years	332,118	427,625
Notional Amount Maturing, Less than 3 years	616,891	368,548
Notional Amount Maturing, Less than 4 years	464,360	699,796
Notional Amount Maturing, Thereafter	1,742,093	1,729,538
Total	3,504,381	3,505,840
Fair Value	$ 70,394	$ 58,853
Derivatives not designed as hedging instruments \| Risk participation-out agreements
Derivatives and Hedging Activities
Number of Positions \| derivative	87	87
Notional Amount Maturing, Less than 1 year	$ 67,441	$ 41,361
Notional Amount Maturing, Less than 2 years	44,412	65,257
Notional Amount Maturing, Less than 3 years	145,481	37,270
Notional Amount Maturing, Less than 4 years	52,348	155,480
Notional Amount Maturing, Thereafter	371,525	371,466
Total	681,207	670,834
Fair Value	$ 575	$ 532
Derivatives not designed as hedging instruments \| Risk participation-in agreements
Derivatives and Hedging Activities
Number of Positions \| derivative	22	23
Notional Amount Maturing, Less than 1 year	$ 28,039	$ 29,862
Notional Amount Maturing, Less than 2 years	6,855	10,321
Notional Amount Maturing, Less than 3 years	26,083	26,468
Notional Amount Maturing, Less than 4 years	18,313	18,473
Notional Amount Maturing, Thereafter	67,779	68,061
Total	147,069	153,185
Fair Value	$ 141	$ 139
Derivatives not designed as hedging instruments \| Foreign exchange contracts \| Buys foreign currency, sells U.S. currency
Derivatives and Hedging Activities
Number of Positions \| derivative	11	9
Notional Amount Maturing, Less than 1 year	$ 2,965	$ 2,785
Notional Amount Maturing, Less than 2 years	0	0
Notional Amount Maturing, Less than 3 years	0	0
Notional Amount Maturing, Less than 4 years	0	0
Notional Amount Maturing, Thereafter	0	0
Total	2,965	2,785
Fair Value	$ 125	$ 274
Derivatives not designed as hedging instruments \| Foreign exchange contracts \| Sells foreign currency, buys U.S. currency
Derivatives and Hedging Activities
Number of Positions \| derivative	11	9
Notional Amount Maturing, Less than 1 year	$ 2,978	$ 2,800
Notional Amount Maturing, Less than 2 years	0	0
Notional Amount Maturing, Less than 3 years	0	0
Notional Amount Maturing, Less than 4 years	0	0
Notional Amount Maturing, Thereafter	0	0
Total	2,978	2,800
Fair Value	$ 235	$ 258

Beacon Financial Corp 10-Q