CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flows from Operating Activities:
Net income	$ 95,822	$ 45,292	$ 107,936
Adjustments to reconcile net income to net cash from operating activities:
Depreciation	63,759	37,919	40,216
Amortization of intangible assets	3,543	3,715	13,486
Share-based compensation expense	13,423	9,477	18,615
Excess income tax benefit from share-based compensation	(269)	(186)	(787)
Change in debt discount and deferred debt issuance costs	10,968	2,095	2,270
Deferred income taxes	(10,169)	22,214	21,460
Loss on sale of investments			1,786
(Gain) loss on sale of property and equipment	453	(2,909)	801
Other long-term liabilities	28,210	28,912	3,074
Other non-cash items	(1,874)	(3,680)	3,273
Changes in other components of working capital	(90,530)	(128,777)	(268,808)
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	113,336	14,072	(56,678)
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisition of property and equipment excluding financed purchases	(15,743)	(35,912)	(75,013)
Proceeds from sale of property and equipment	1,899	4,980	5,335
Proceeds from sale of investments			44,497
Change in restricted cash	(4,651)	(1,483)	(1,776)
NET CASH USED IN INVESTING ACTIVITIES	(18,495)	(32,415)	(26,957)
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of convertible notes	200,000
Proceeds from debt	1,353,895	1,013,205	1,156,739
Repayment of debt	(1,562,684)	(1,054,371)	(1,026,349)
Payments related to business acquisitions			(26,430)
Excess income tax benefit from share-based compensation	269	186	787
Issuance of common stock and effect of cashless exercise	(584)	(808)	(1,771)
Debt issuance costs	(15,086)		(3,681)
NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES	(24,190)	(41,788)	99,295
Net (decrease) increase in cash and cash equivalents	70,651	(60,131)	15,660
Cash and cash equivalents at beginning of year	75,452	135,583	119,923
Cash and cash equivalents at end of year	$ 146,103	$ 75,452	$ 135,583