Consolidated Statements of Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Parent [Member]	Noncontrolling Interest [Member]	Total
Balance (in shares) at Dec. 31, 2016	20,712,166
Balance at Dec. 31, 2016	$ 207	$ 197,161	$ 47,155	$ 244,523	$ 101	$ 244,624
Net income (loss)	0	0	17,152	17,152	(11)	17,141
Stock-based compensation expense	$ 0	2,803	0	2,803	0	2,803
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans (in shares)	(56,092)
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans	$ 0	(590)	0	(590)	0	(590)
Shares issued through stock plans (in shares)	220,763
Shares issued through stock plans	$ 2	100	0	102	0	102
Balance (in shares) at Dec. 31, 2017	20,876,837
Balance at Dec. 31, 2017	$ 209	199,474	64,307	263,990	90	264,080
Net income (loss)	0	0	(14,216)	(14,216)	(14)	(14,230)
Stock-based compensation expense	$ 0	3,090	0	3,090	0	3,090
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans (in shares)	(86,692)
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans	$ 0	(982)	0	(982)	0	(982)
Shares issued through stock plans (in shares)	271,875
Shares issued through stock plans	$ 2	(2)	0	0	0	0
Adoption of ASC 606 and ASU 2018-07 (see Note 1) at Dec. 31, 2017	$ 0	(18)	(3,347)	(3,365)	0	$ (3,365)
Repurchase of common stock (in shares)	(1,003,116)					(1,003,116)
Repurchase of common stock	$ (10)	(8,430)	(123)	(8,563)	0	$ (8,563)
Balance (in shares) at Dec. 31, 2018	20,058,904					20,058,904
Balance at Dec. 31, 2018	$ 201	193,132	46,621	239,954	76	$ 240,030
Net income (loss)	0	0	(8,037)	(8,037)	36	(8,001)
Stock-based compensation expense	$ 0	2,260	0	2,260	0	2,260
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans (in shares)	(85,420)
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans	$ 0	(488)	0	(488)	0	(488)
Shares issued through stock plans (in shares)	277,401
Shares issued through stock plans	$ 2	(2)	0	0	0	$ 0
Repurchase of common stock (in shares)	(153,916)					(153,916)
Repurchase of common stock	$ (2)	(1,040)	0	(1,042)	0	$ (1,042)
Balance (in shares) at Dec. 31, 2019	20,096,969					20,096,969
Balance at Dec. 31, 2019	$ 201	$ 193,862	$ 38,584	$ 232,647	$ 112	$ 232,759