CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash Flows from Operating Activities:
Net income	$ 48,644	$ 70,159
Amounts to reconcile net income to net cash flows provided by (used in) operating activities:
Income from discontinued operations, net of taxes	(23)	(21)
Impairment and other charges		1,786
Benefit for deferred income taxes	(1,088)	(69,493)
Depreciation and amortization	56,235	61,063
Amortization of deferred financing costs	2,837	2,642
Amortization of discount on convertible notes	6,028	7,337
Write-off of deferred financing costs		1,845
Loss on extinguishment of debt	2,148
Stock-based compensation expense	2,728	4,635
Excess tax benefit from stock-based compensation	(12)	(4)
Changes in:
Trade receivables	(4,135)	(19,107)
Interest receivable	(2,609)	(2,578)
Accounts payable and accrued liabilities	(23,579)	(72,198)
Other assets and liabilities	4,740	4,947
Net cash flows provided by (used in) operating activities - continuing operations	91,914	(8,987)
Net cash flows provided by (used in) operating activities - discontinued operations	(205)	79
Net cash flows provided by (used in) operating activities	91,709	(8,908)
Cash Flows from Investing Activities:
Purchases of property and equipment	(35,773)	(15,181)
(Increase) decrease in restricted cash and cash equivalents	6,268	(8,273)
Other investing activities	398	226
Net cash flows used in investing activities - continuing operations	(29,107)	(23,228)
Net cash flows used in investing activities - discontinued operations
Net cash flows used in investing activities	(29,107)	(23,228)
Cash Flows from Financing Activities:
Net borrowings (repayments) under credit facility	190,500	(82,000)
Issuance of senior notes		350,000
Early redemption of senior notes		(152,180)
Repurchase and conversion of convertible notes	(126,541)
Repurchase of common stock warrants	(50,775)
Deferred financing costs paid	(8,158)	(15,395)
Repurchase of Company stock for retirement		(100,028)
Payment of dividend	(53,389)	(25,823)
Proceeds from exercise of stock option and purchase plans	2,309	5,145
Excess tax benefit from stock-based compensation	12	4
Other financing activities, net	(296)	(357)
Net cash flows used in financing activities - continuing operations	(46,338)	(20,634)
Net cash flows used in financing activities - discontinued operations
Net cash flows used in financing activities	(46,338)	(20,634)
Net change in cash and cash equivalents	16,264	(52,770)
Cash and cash equivalents - unrestricted, beginning of period	61,579	97,170
Cash and cash equivalents - unrestricted, end of period	$ 77,843	$ 44,400