Significant Accounting Policies - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Earnings Per Share Reconciliation [Abstract]
Net income (loss)	$ 47,493	$ (89,698)	$ 177,140
Weighted average common shares outstanding - basic	196,550	80,018
Weighted average common shares outstanding - diluted	196,550	80,018
Net income (loss) per common share - basic	$ 0.24	$ (1.12)
Net income (loss) per common share - diluted	$ 0.24	$ (1.12)