Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets, Current [Abstract]
Cash and Cash Equivalents	$ 282,223	$ 292,656
Receivables, net	150,260	115,446
Inventories	79,945	70,941
Prepaid expenses and other current assets	7,893	6,130
Total current assets	520,321	485,173
Restricted cash	781	781
Property, plant, and equipment, net	326,404	162,232
Deferred income taxes	52	1,311
Other assets	1,028	853
Total assets	848,586	650,350
Liabilities, Current [Abstract]
Current maturities of long-term debt	4,000	3,960
Accounts payable	63,979	35,238
Other current liabilities	70,994	59,629
Total current liabilities	138,973	98,827
Long-term debt	389,914	379,177
Deferred income taxes	7,095	12,660
Other long-term liabilities	13,468	13,348
Total liabilities	549,450	504,012
Commitments and Contingencies
Preferred stock	0	0
Common stock	1,976	1,965
Additional paid-in capital	81,113	71,420
Retained earnings (accumulated deficit)	266,221	72,692
Accumulated other comprehensive income (loss)	(174)	261
Treasury stock, at cost	(50,000)	0
Total stockholders' equity	299,136	146,338
Total liabilities and stockholders' equity	$ 848,586	$ 650,350
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	1,500,000,000	1,500,000,000
Common shares outstanding (in shares)	195,522,290	196,524,010
Common Stock, Shares, Issued	197,615,064	196,524,010
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	150,000,000	150,000,000
Preferred Stock, Shares Outstanding	0	0
Preferred Stock, Shares Issued	0	0
Treasury Stock, Common, Shares	2,092,774	0