CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Total
Balance at Dec. 31, 2011	$ 47,329	$ 993,434	$ 402,679	$ (43,615)	$ 1,399,827
Net income (loss)			(265,400)		(265,400)
Other comprehensive income (loss)				41	41
TOTAL COMPREHENSIVE INCOME (LOSS)					(265,359)
Tax effect of stock-based compensation		(195)			(195)
Stock-based compensation expense		9,470			9,470
Issuance of common stock, net	227	(106)			121
Balance at Dec. 31, 2012	47,556	1,002,603	137,279	(43,574)	1,143,864
Net income (loss)			87,296		87,296
Other comprehensive income (loss)				10,195	10,195
TOTAL COMPREHENSIVE INCOME (LOSS)					97,491
Tax effect of stock-based compensation		(7)			(7)
Stock-based compensation expense		6,623			6,623
Issuance of common stock, net	865	(1,301)			(436)
Balance at Dec. 31, 2013	48,421	1,007,918	224,575	(33,379)	1,247,535
Net income (loss)			107,936		107,936
Other comprehensive income (loss)				(8,240)	(8,240)
TOTAL COMPREHENSIVE INCOME (LOSS)					99,696
Tax effect of stock-based compensation		786			786
Stock-based compensation expense		18,616			18,616
Issuance of common stock, net	250	(1,378)			(1,128)
Balance at Dec. 31, 2014	$ 48,671	$ 1,025,942	$ 332,511	$ (41,619)	$ 1,365,505