Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Retained Earnings	Total
Balance at the beginning at Dec. 31, 2017	$ 345	$ 1,628,355	$ (654,332)	$ 974,368
Increase (Decrease) in Shareholders' Equity
Net loss			(55,813)	(55,813)
Nonvested stock amortization		493		493
Balance at the end at Mar. 31, 2018	345	1,628,848	(710,145)	919,048
Increase (Decrease) in Shareholders' Equity
Net loss			(1,118)	(1,118)
Issuance of 7,015,000 shares of common stock	70	109,605		109,675
Nonvested stock amortization		638		638
Balance at the end at Jun. 30, 2018	415	1,739,091	(711,263)	1,028,243
Increase (Decrease) in Shareholders' Equity
Net loss			5,707	5,707
Issuance of 7,015,000 shares of common stock		(12)		(12)
Nonvested stock amortization		645		645
Balance at the end at Sep. 30, 2018	415	1,739,724	(705,556)	1,034,583
Balance at the beginning at Dec. 31, 2018	416	1,740,163	(687,272)	1,053,307
Increase (Decrease) in Shareholders' Equity
Net loss			(7,801)	(7,801)
Nonvested stock amortization		452		452
Balance at the end at Mar. 31, 2019	416	1,740,615	(695,073)	1,045,958
Increase (Decrease) in Shareholders' Equity
Net loss			(34,476)	(34,476)
Nonvested stock amortization		569		569
Balance at the end at Jun. 30, 2019	416	1,741,184	(729,549)	1,012,051
Increase (Decrease) in Shareholders' Equity
Net loss			(14,591)	(14,591)
Nonvested stock amortization		575		575
Balance at the end at Sep. 30, 2019	$ 416	$ 1,741,759	$ (744,140)	$ 998,035