CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash Flows from Operating Activities:
Net income	$ 97,781	$ 154,544	$ 95,822
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	43,724	48,387	63,759
Amortization of intangible assets	3,543	3,543	3,543
Share-based compensation expense	22,782	21,174	13,423
Excess income tax benefit from share-based compensation			(269)
Change in debt discounts and deferred debt issuance costs	12,072	17,595	10,968
Deferred income taxes	(449)	(23,096)	(10,169)
Loss on sale of property and equipment	402	1,131	453
Changes in other components of working capital	(156,844)	(60,214)	(90,530)
Other long-term liabilities	(2,007)	3,656	28,210
Other, net	398	(3,170)	(1,874)
NET CASH PROVIDED BY OPERATING ACTIVITIES	21,402	163,550	113,336
Cash Flows from Investing Activities:
Acquisition of property and equipment	(77,069)	(30,280)	(15,743)
Proceeds from sale of property and equipment	6,387	2,744	1,899
Investments in securities	(20,848)	(60,967)
Proceeds from maturities and sales of investments in securities	21,322	1,370
NET CASH USED IN INVESTING ACTIVITIES	(70,208)	(87,133)	(13,844)
Cash Flows from Financing Activities:
Proceeds from debt	1,753,160	2,161,384	1,353,895
Repayment of debt	(1,738,314)	(2,195,068)	(1,562,684)
Business acquisition related payment	(15,951)
Issuance of convertible notes			200,000
Cash payments related to share-based compensation	(2,671)	(11,769)	(584)
Excess income tax benefit from share-based compensation			269
Distributions paid to noncontrolling interests	(29,000)	(17,499)
Contributions from noncontrolling interests	3,797	2,842
Debt issuance and extinguishment costs		(15,266)	(15,086)
NET CASH USED IN FINANCING ACTIVITIES	(28,979)	(75,376)	(24,190)
Net increase (decrease) in cash, cash equivalents and restricted cash	(77,785)	1,041	75,302
Cash, cash equivalents and restricted cash at beginning of year	197,648	196,607	121,305
Cash, cash equivalents and restricted cash at end of year	$ 119,863	$ 197,648	$ 196,607