Capital Stock (Details) - USD ($) $ / shares in Units, $ in Thousands		6 Months Ended	12 Months Ended
	Dec. 09, 2016	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Shares Issued, Price Per Share		$ 5.50				$ 5.15	$ 11.43
Proceeds from Issuance of Common Stock	$ 109,700	$ 60,200	$ 10	$ 152,657
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 5.75
Warranty Liability						$ 13,202		$ 18,503
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right						11,200,000
Fair Value Adjustment of Warrants			$ (5,301)	2,106	$ 0
Warrants Issuance Cost charged to Earnings				$ 900
Total number of new units issued			0	33,810,000	0
Issuance Costs, Warrants				$ 6,500
underwriters option to purchase			2,900,000
per share net of underwrtiter discount		$ 5.2525	$ 4.9183
Common Stock, Shares, Issued	22,300,000	11,500,000				118,515,797		117,521,493
Unitssubjecttounderwritersoption		1,500,000
Common stock, shares authorized						250,000,000		150,000,000
Common stock, par value (in dollars per share)						$ 0.01		$ 0.01
Preferred stock, shares authorized						5,000,000
Preferred stock, par value						$ 0.01
Common Stock, Shares, Outstanding		114,985,072	114,985,072	80,256,544	79,649,946	115,877,704		114,985,072
Treasury stock, shares held		2,536,421	2,536,421	2,281,495	2,224,285	2,638,093		2,536,421
Preferred stock, shares issued						0
Common Shares Outstanding and Treasury Shares Held Rollforward [Table]
Common shares outstanding, beginning balance		114,985,072	114,985,072	80,256,544	79,649,946
Exercise of common stock options, net			0	636,937	67,808
Grants of restricted stock, net			892,632	281,591	538,790
Common shares outstanding, ending balance			115,877,704	114,985,072	80,256,544
Treasury stock, beginning balance		2,536,421	2,536,421	2,281,495	2,224,285
Shares received upon exercise of common stock options			0	13,854	36,818
Shares received upon vesting of restricted stock, net			101,672	241,072	20,392
Treasury stock, ending balance			2,638,093	2,536,421	2,281,495
Amount authorized under stock repurchase program						$ 20,000
Amount repurchased under the stock repurchase program in the period			0