Debt Obligations - Long-term Debt Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Borrowings under senior credit facility	$ 323,281	$ 148,508
Other long-term debt	51,254	46,981
Finance leases	2,412	2,228
Total long-term debt obligations	1,364,718	1,184,825
Less — Current maturities of long-term debt	11,176	10,531
Total long-term debt obligations, net of current maturities	1,353,542	1,174,294
2.900% Senior Notes due 2030 \| Senior Notes
Debt Instrument [Line Items]
2.900% Senior Notes due 2030	1,000,000	1,000,000
Unamortized discount and debt issuance costs related to senior notes	$ (12,229)	$ (12,892)
Interest rate	2.90%

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and lease obligation, including portion classified as current.

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