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v3.23.1

Other Balance Sheet Information (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
Cash and Cash Equivalents [Line Items] |  |  |  |
Overnight Holdings | $ 635,931 | $ 678,512 |  |
Short-term Investments | 91,081 | 90,031 |  |
Cash | 21,072 | 41,047 |  |
Drafts Payable | (15,961) | (43,694) |  |
Cash, Cash Equivalents, and Short-term Investments | 732,123 | 765,896 |  |
Client Prepayments Included in Cash Balance | (42,900) | (36,800) |  |
Payroll Withholdings Included in Cash Balance | 457,800 | 504,800 |  |
Supplemental Cash Flow Elements [Abstract] |  |  |  |
Restricted cash | 48,113 | 49,779 | $ 49,429 | $ 46,929
Funds Held for Clients | 41,552 | 34,942 | 0 | 0
Deposits workers compensation | 211,226 | 196,370 | 190,756 | 185,027
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents | 997,479 | 1,013,919 | $ 816,839 | $ 807,768
Money Market Funds [Member] |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |
Overnight Holdings | 0 | 0 |  |
Short-term Investments | 35,535 | 33,068 |  |
Cash | 0 | 0 |  |
Drafts Payable | 0 | 0 |  |
Cash, Cash Equivalents, and Short-term Investments | 35,535 | 33,068 |  |
Cash and Cash Equivalents [Member] |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |
Overnight Holdings | 635,931 | 678,512 |  |
Short-term Investments | 55,546 | 56,963 |  |
Cash | 21,072 | 41,047 |  |
Drafts Payable | (15,961) | (43,694) |  |
Cash, Cash Equivalents, and Short-term Investments | $ 696,588 | $ 732,828 |  |

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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, these investments are only held overnight. + References No definition available. + Details
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481372/852-10-55-10 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480167/946-830-55-12 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(4)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 45 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480555/946-210-45-21 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 45 -Paragraph 20 -SubTopic 210 -Topic 946 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480555/946-210-45-20 + Details
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- Definition Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(9)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Carrying amount as of the balance sheet date of the funds held on behalf of others and that are expected to be liquidated within one year or the normal operating cycle, if longer. This does not include funds held under reinsurance agreements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(8)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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