v3.25.2

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Jun. 30, 2024
Stockholders' Equity Note [Abstract]
Aggregate number of shares repurchased during the period (in shares)					224,867
Shares repurchased under the program (in shares)					45,000
Authorized to repurchased additional shares under repurchase program (in shares)	1,407,764				1,407,764
Shares withheld for tax withholding obligations for the vesting of restricted stock awards (in shares)					179,867
Dividends declared per share of common stock (in dollars per share)	$ 0.60	$ 0.60	$ 0.60	$ 0.57
Payments of Ordinary Dividends, Common Stock					$ (45)	$ (44)

Aggregate number of shares repurchased during the period.

+ References

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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No definition available.

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- Definition

Number of shares remaining authorized to be purchased under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

+ References

No definition available.

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- References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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INSPERITY, INC. 10-Q