Condensed Consolidated Statements of Redeemable Preferred Stock and Shareholders' Equity - USD ($) $ in Thousands	Total	Redeemable Preferred Stock	Common Stock	Paid in Capital in Excess of Par	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balances, beginning of period (in shares) at Dec. 31, 2018		2,500,000	6,176,000
Balances, beginning of period at Dec. 31, 2018	$ 286,787	$ 49,554	$ 62	$ 0	$ 286,623	$ 102
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	37,853				37,853
Net unrealized loss from currency translation adjustment, net of tax benefit (expense)	(26)					(26)
Net unrealized loss from derivative instruments, net of tax benefit (expense)	$ (1,304)					(1,304)
Shares repurchased (in shares)	(72,324)		(72,000)
Shares repurchased	$ (3,567)		$ (1)	(2,087)	(1,479)
Shares issued under stock compensation plans (in shares)			283,000
Shares issued under stock compensation plans	163		$ 3	160
Cancellation of restricted stock in satisfaction of withholding tax (in shares)			(37,000)
Cancellation of restricted stock in satisfaction of withholding tax	(1,460)		$ 0	(1,460)
Stock-based compensation expense	3,387			3,387
Accretion of preferred shares issuance costs	(42)	$ 42			(42)
Preferred stock dividends	(1,611)				(1,611)
Balances, end of period (in shares) at Jun. 30, 2019		2,500,000	6,350,000
Balances, end of period at Jun. 30, 2019	320,413	$ 49,596	$ 64	0	321,577	(1,228)
Balances, beginning of period (in shares) at Mar. 31, 2019		2,500,000	6,160,000
Balances, beginning of period at Mar. 31, 2019	307,438	$ 49,575	$ 62	563	306,912	(99)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	16,975				16,975
Net unrealized loss from currency translation adjustment, net of tax benefit (expense)	(299)					(299)
Net unrealized loss from derivative instruments, net of tax benefit (expense)	(830)					(830)
Shares repurchased (in shares)			(65,000)
Shares repurchased	(3,251)		$ (1)	(1,771)	(1,479)
Shares issued under stock compensation plans (in shares)			277,000
Shares issued under stock compensation plans	3		$ 3	0
Cancellation of restricted stock in satisfaction of withholding tax (in shares)			(22,000)
Cancellation of restricted stock in satisfaction of withholding tax	(914)		$ 0	(914)
Stock-based compensation expense	2,122			2,122
Accretion of preferred shares issuance costs	(21)	$ 21			(21)
Preferred stock dividends	(810)				(810)
Balances, end of period (in shares) at Jun. 30, 2019		2,500,000	6,350,000
Balances, end of period at Jun. 30, 2019	320,413	$ 49,596	$ 64	0	321,577	(1,228)
Balances, beginning of period (in shares) at Dec. 31, 2019		2,500,000	6,356,000
Balances, beginning of period at Dec. 31, 2019	350,338	$ 49,638	$ 64	4,557	348,965	(3,248)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	9,658				9,658
Net unrealized loss from currency translation adjustment, net of tax benefit (expense)	(176)					(176)
Net unrealized loss from derivative instruments, net of tax benefit (expense)	$ (2,937)					(2,937)
Shares repurchased (in shares)	(54,626)		(55,000)
Shares repurchased	$ (1,490)		$ 0	(1,490)	0
Shares issued under stock compensation plans (in shares)			311,000
Shares issued under stock compensation plans	200		$ 3	197
Cancellation of restricted stock in satisfaction of withholding tax (in shares)			(60,000)
Cancellation of restricted stock in satisfaction of withholding tax	(1,194)		$ (1)	(1,193)
Stock-based compensation expense	5,132			5,132
Accretion of preferred shares issuance costs	(42)	$ 42			(42)
Preferred stock dividends	(1,621)				(1,621)
Balances, end of period (in shares) at Jun. 30, 2020		2,500,000	6,552,000
Balances, end of period at Jun. 30, 2020	357,868	$ 49,680	$ 66	7,203	356,960	(6,361)
Balances, beginning of period (in shares) at Mar. 31, 2020		2,500,000	6,344,000
Balances, beginning of period at Mar. 31, 2020	353,007	$ 49,659	$ 63	6,527	352,420	(6,003)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,372				5,372
Net unrealized loss from currency translation adjustment, net of tax benefit (expense)	(5)					(5)
Net unrealized loss from derivative instruments, net of tax benefit (expense)	(353)					(353)
Shares repurchased (in shares)			(55,000)
Shares repurchased	(1,490)			(1,490)
Shares issued under stock compensation plans (in shares)			307,000
Shares issued under stock compensation plans	0		$ 3	(3)
Cancellation of restricted stock in satisfaction of withholding tax (in shares)			(44,000)
Cancellation of restricted stock in satisfaction of withholding tax	(846)		$ 0	(846)
Stock-based compensation expense	3,015			3,015
Accretion of preferred shares issuance costs	(21)	$ 21			(21)
Preferred stock dividends	(811)				(811)
Balances, end of period (in shares) at Jun. 30, 2020		2,500,000	6,552,000
Balances, end of period at Jun. 30, 2020	$ 357,868	$ 49,680	$ 66	$ 7,203	$ 356,960	$ (6,361)