CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 167,528	$ 356,948	$ 171,474
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of intangibles and right-of-use assets	184,449	153,726	130,629
Impairment of right-of-use asset	2,012	5,874	0
Deferred taxes	9,587	4,448	(3,992)
Compensation expense related to share-based compensation plans	21,348	20,426	20,056
Gain on sale of assets	(6,835)	(24,176)	(19,173)
Changes in operating assets and liabilities, net of acquisitions:
Restricted investments	(2,698)	6,191	(903)
Accounts receivable, net	145,088	8,298	(115,568)
Prepaid taxes	(344)	(14,796)	(856)
Prepaid expenses and other current assets	(5,974)	(3,111)	(647)
Other assets	(3,732)	(4,231)	(2,883)
Accounts payable	1,215	(89,103)	78,448
Accrued expenses	(63,626)	57,613	9,686
Non-current liabilities	(25,860)	(19,944)	(13,436)
Net cash provided by operating activities	422,158	458,163	252,835
Cash flows from investing activities:
Proceeds from sale of equipment	27,717	42,929	45,177
Purchases of property and equipment	(140,068)	(219,140)	(132,952)
Acquisitions, net of cash acquired	(260,810)	(102,661)	(122,360)
Net cash used in investing activities	(373,161)	(278,872)	(210,135)
Cash flows from financing activities:
Purchase of treasury stock	(143,770)	(75,000)	0
Repayments of long-term debt	(105,771)	(111,482)	(107,608)
Stock tendered for payments of withholding taxes	(10,148)	(8,312)	(9,123)
Finance lease payments	(2,708)	(2,093)	(2,682)
Purchase of treasury stock from related party (Note 17)	0	(34,767)	0
Proceeds from issuance of debt	113,988	179,195	112,001
Net cash used in financing activities	(148,409)	(52,459)	(7,412)
Effect of exchange rate changes on cash and cash equivalents	40	26	(10)
Net increase (decrease) in cash and cash equivalents	(99,372)	126,858	35,278
Cash and cash equivalents beginning of the year	286,642	159,784	124,506
Cash and cash equivalents end of the year	187,270	286,642	159,784
Supplemental disclosures of cash paid for:
Interest	12,510	7,991	7,602
Income taxes	$ 34,882	$ 128,812	$ 58,593