v3.25.4

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended						12 Months Ended
	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Aggregate number of shares repurchased during the period (in shares)							231,668
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)							186,668
Dividends declared per share of common stock (in dollars per share)	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.57
Payments of Ordinary Dividends, Common Stock							$ (90)	$ (89)	$ (84)
Preferred Stock, Shares Authorized	20,000,000			20,000,000			20,000,000	20,000,000

Aggregate number of shares repurchased during the period.

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- Definition

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

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- Definition

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

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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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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- 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.

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No definition available.

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

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INSPERITY, INC. 10-K