Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows from Operating Activities:
Net income	$ 91,319	$ 41,503
Adjustments to reconcile net income to net cash provided by operating activities—
Depreciation	62,107	54,410
Amortization of intangible assets	21,355	17,908
Change in fair value of contingent consideration liabilities	(363)	2,758
Equity in (earnings) losses of unconsolidated affiliates	(5,868)	2,683
Amortization of debt discount and issuance costs	846	589
Gain on sale of property and equipment	(4,982)	(814)
Provision for credit losses	43	273
Deferred income tax provision	2,494	4,210
Non-cash stock-based compensation	18,687	14,912
Foreign currency gain	(576)	(353)
Changes in operating assets and liabilities, net of non-cash transactions	(59,449)	89,470
Net cash provided by operating activities	125,613	227,549
Cash Flows from Investing Activities:
Capital expenditures	(83,486)	(68,109)
Proceeds from sale of property and equipment	7,223	4,790
Proceeds from insurance settlements related to property and equipment	7	198
Cash paid for acquisitions, net of cash, cash equivalents and restricted cash acquired	(32,778)	(22,794)
Proceeds from disposition of businesses	0	2,474
Investments in unconsolidated affiliates and other	(113,982)	(5,692)
Cash received from investments in unconsolidated affiliates and other entities	210	0
Net cash used in investing activities	(222,806)	(89,133)
Cash Flows from Financing Activities:
Borrowings under credit facility	828,496	1,474,452
Payments under credit facility	(656,818)	(1,171,059)
Payments of other long-term debt	(857)	(446)
Net repayments of short-term debt, net of borrowings	(4,247)	(2,799)
Payments for contingent consideration liabilities	(263)	(989)
Distributions to non-controlling interests	(1,129)	(1,963)
Payments related to tax withholding for stock-based compensation	(23,921)	(15,886)
Payment of dividends	(8,798)	(7,384)
Repurchase of common stock	(19,474)	(200,000)
Net cash provided by financing activities	112,989	73,926
Effect of foreign exchange rate changes on cash, cash equivalents and restricted cash	11	(449)
Net increase in cash, cash equivalents and restricted cash	15,807	211,893
Cash, cash equivalents and restricted cash, beginning of period	186,808	169,745
Cash, cash equivalents and restricted cash, end of period	$ 202,615	$ 381,638