CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flows from Operating Activities:
Net income	$ 154,544	$ 95,822	$ 45,292
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	48,387	63,759	37,919
Amortization of intangible assets	3,543	3,543	3,715
Share-based compensation expense	21,174	13,423	9,477
Excess income tax benefit from share-based compensation		(269)	(186)
Change in debt discounts and deferred debt issuance costs	17,595	10,968	2,095
Deferred income taxes	(23,096)	(10,169)	22,214
Loss (gain) on sale of property and equipment	1,131	453	(2,909)
Changes in other components of working capital	(60,214)	(90,530)	(128,777)
Other long-term liabilities	3,656	28,210	28,912
Other	(3,170)	(1,874)	(3,680)
NET CASH PROVIDED BY OPERATING ACTIVITIES	163,550	113,336	14,072
Cash Flows from Investing Activities:
Acquisition of property and equipment	(30,280)	(15,743)	(35,912)
Proceeds from sale of property and equipment	2,744	1,899	4,980
Investments in securities, restricted	(54,504)
Investments in securities	(6,463)
Proceeds from maturities of investments in securities	1,370
Change in restricted cash	45,724	(4,651)	(1,483)
NET CASH USED IN INVESTING ACTIVITIES	(41,409)	(18,495)	(32,415)
Cash Flows from Financing Activities:
Proceeds from debt	2,161,384	1,353,895	1,013,205
Repayment of debt	(2,195,068)	(1,562,684)	(1,054,371)
Issuance of convertible notes		200,000
Debt issuance and extinguishment costs	(15,266)	(15,086)
Cash payments related to share-based compensation	(11,769)	(584)	(808)
Excess income tax benefit from share-based compensation		269	186
Distributions paid to noncontrolling interests	(17,499)
Contributions from noncontrolling interests	2,842
NET CASH USED IN FINANCING ACTIVITIES	(75,376)	(24,190)	(41,788)
Net increase (decrease) in cash and cash equivalents	46,765	70,651	(60,131)
Cash and cash equivalents at beginning of year	146,103	75,452	135,583
Cash and cash equivalents at end of year	$ 192,868	$ 146,103	$ 75,452

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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The cash outflow for loan and debt issuance costs.

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