Earnings (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	May 20, 2013
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income (loss)	$ 9,019	$ 52,406	$ 89,937	$ (66,489)
Effect of dilutive securities:
Income (loss) to common stockholders plus assumed conversions	$ 13,434	$ 55,314	$ 100,259	$ (66,489)
Weighted average common shares outstanding:
Basic shares outstanding (in shares)	1,264,516	1,169,993	1,263,416	1,137,854
Incremental shares from assumed exercises, conversions and other issuance of:
Stock options, restricted stock, restricted stock units and ESPP (in shares)	2,370	7,364	5,661	0
Diluted shares outstanding (in shares)	1,427,800	1,345,905	1,448,920	1,137,854
Net income (loss) per share:
Basic (USD per share)	$ 0.01	$ 0.04	$ 0.07	$ (0.06)
Diluted (USD per share)	$ 0.01	$ 0.04	$ 0.07	$ (0.06)
Antidilutive shares excluded from computation of earnings per share (in shares)				171,500
8.00% Convertible Senior Notes Issued in 2013
Effect of dilutive securities:
Dilutive securities	$ 28	$ 388	$ 66	$ 0
Incremental shares from assumed exercises, conversions and other issuance of:
Conversion of debt securities (in shares)	1,867	2,157	2,087	0
Loan Agreement with Thermo
Effect of dilutive securities:
Dilutive securities	$ 4,387	$ 2,520	$ 10,256	$ 0
Incremental shares from assumed exercises, conversions and other issuance of:
Conversion of debt securities (in shares)	159,047	166,391	177,756	0
8.00% Convertible Senior Notes Issued in 2013
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Loan interest rate	8.00%		8.00%		8.00%