CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Total
Balance at Dec. 31, 2016	$ 225	$ 144,523	$ 82,387	$ (6,672)	$ 220,463
Balance (in shares) at Dec. 31, 2016	22,501,640
Increase (Decrease) in Stockholders' Equity
Net loss			55,324		55,324
Dividends paid			(21,974)		(21,974)
Prior period adjustment		187
Adjustment for pension and postretirement benefit liability, net of tax of ($94) in 2019, ($558) in 2018 and ($140) in 2017				233	233
Adjustment for interest rate swap, net of tax of $1,211 in 2019, ($64) in 2018 and $88 in 2017				(133)	(133)
Shares withheld on restricted stock vesting		(923)			(923)
Stock based compensation	$ 1	3,500			3,501
Stock based compensation (in shares)	89,257
Balance at Dec. 31, 2017	$ 226	147,287	115,737	(6,572)	256,678
Balance (in shares) at Dec. 31, 2017	22,590,897
Increase (Decrease) in Stockholders' Equity
Net loss			43,905		43,905
Dividends paid			(24,383)		(24,383)
Prior period adjustment | ASC 2014-09			377
Adjustment for pension and postretirement benefit liability, net of tax of ($94) in 2019, ($558) in 2018 and ($140) in 2017				1,568	1,568
Adjustment for interest rate swap, net of tax of $1,211 in 2019, ($64) in 2018 and $88 in 2017				84	84
Shares withheld on restricted stock vesting		(23)			(23)
Stock based compensation	$ 1	4,549			4,550
Stock based compensation (in shares)	110,094
Balance at Dec. 31, 2018	$ 227	151,813	136,765	(6,049)	282,756
Balance (in shares) at Dec. 31, 2018	22,700,991
Increase (Decrease) in Stockholders' Equity
Impact due to adoption			1,129	(1,129)
Net loss			49,166		49,166
Dividends paid			(25,183)		(25,183)
Adjustment for pension and postretirement benefit liability, net of tax of ($94) in 2019, ($558) in 2018 and ($140) in 2017				351	351
Adjustment for interest rate swap, net of tax of $1,211 in 2019, ($64) in 2018 and $88 in 2017				(3,496)	(3,496)
Pension termination, net of tax of ($2,237)				6,380	6,380
Shares withheld on restricted stock vesting		(50)			(50)
Stock based compensation	$ 1	3,238			3,239
Stock based compensation (in shares)	94,421
Balance at Dec. 31, 2019	$ 228	$ 155,001	$ 160,748	$ (2,814)	$ 313,163
Balance (in shares) at Dec. 31, 2019	22,795,412