Condensed Consolidated Statements of Changes in Stockholders' Equity - 9 months ended Sep. 30, 2016 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Balances at Dec. 31, 2015	$ 421,476	$ 1,513	$ 3,024,461	$ (2,600,776)	$ (3,722)
Balances, in shares at Dec. 31, 2015		151,339
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	63,660	$ 0	0	63,660	0
Other comprehensive income (loss)	1,862	$ 0	0	0	1,862
Common stock issued under stock-based compensation plans, net (in shares)		1,940
Stock Issued During Period, Shares, New Issues		14,286
Stock Issued During Period, Value, New Issues	138,324	$ 143	138,181	0	0
Common stock issued under stock-based compensation plans, net	7,009	20	6,989	0	0
Balances at Sep. 30, 2016	$ 632,331	$ 1,676	$ 3,169,631	$ (2,537,116)	$ (1,860)
Balances, in shares at Sep. 30, 2016		167,565