Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

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Accounting Policies 401k(Details) - USD ($) $ in Millions	12 Months Ended
Accounting Policies 401k(Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Worksite Employee Plan [Member]
Defined Contribution Plan [Abstract]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 374.5	$ 328.5	$ 244.1
Worksite Employee Plan [Member] \| Minimum [Member]
Defined Contribution Plan [Abstract]
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	0.00%
Worksite Employee Plan [Member] \| Maximum [Member]
Defined Contribution Plan [Abstract]
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	6.00%
CorporatePlan [Domain]
Defined Contribution Plan [Abstract]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	6.00%	6.00%	6.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	100.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 16.9	$ 14.4	$ 8.2