CONDENSED STATEMENT OF CHANGES IN STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Common Stock	Preferred Stock	Treasury Stock	Additional Paid in Capital	Retained Earnings
Balance at beginning of period at Dec. 31, 2018		$ 533	$ 0	$ (38,030)	$ 239,827	$ 510,282
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury stock purchase				(12,546)
Stock compensation					3,875
Net income (loss)	$ 280,949					280,949
Dividends paid						(237,814)
Other					(1,244)	105
Balance at end of period at Sep. 30, 2019	745,937	533	0	(50,576)	242,458	553,522
Balance at beginning of period at Jun. 30, 2019		533	0	(40,000)	241,020	511,105
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury stock purchase				(10,576)
Stock compensation					1,438
Net income (loss)	45,022					45,022
Dividends paid						(2,605)
Other					0	0
Balance at end of period at Sep. 30, 2019	745,937	533	0	(50,576)	242,458	553,522
Balance at beginning of period at Dec. 31, 2019	765,582	533	0	(50,576)	243,932	571,693
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury stock purchase				0
Stock compensation					5,247
Net income (loss)	(2,050)					(2,050)
Dividends paid						(7,796)
Other					(1,272)	0
Balance at end of period at Sep. 30, 2020	759,711	533	0	(50,576)	247,907	561,847
Balance at beginning of period at Jun. 30, 2020		533	0	(50,576)	246,126	578,880
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury stock purchase				0
Stock compensation					1,781
Net income (loss)	(14,434)					(14,434)
Dividends paid						(2,599)
Other					0	0
Balance at end of period at Sep. 30, 2020	$ 759,711	$ 533	$ 0	$ (50,576)	$ 247,907	$ 561,847