Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock	Paid-in Capital in Excess of par	Accumulated Other Comprehensive Income	Retained Earnings	Total
Balances at Dec. 31, 2013	$ 84	$ 44,741	$ 325	$ 167,455	$ 212,605
Balances (in shares) at Dec. 31, 2013	8,400
Increase (Decrease) in Shareholders' Equity
Net income				7,525	7,525
Unrealized loss from derivative instruments, net of tax benefit			(236)		(236)
Shares repurchased	$ (2)	(4,005)			(4,007)
Shares repurchased (in shares)	(187)
Shares issued under stock compensation plans	$ 1	409			410
Shares issued under stock compensation plans (in shares)	92
Cancellation of restricted stock units in satisfaction of withholding tax	$ (1)	(1,308)			(1,309)
Cancellation of restricted stock units in satisfaction of withholding tax (in shares)	(66)
Stock-based compensation, net of forfeitures		2,447			2,447
Balances at Sep. 30, 2014	$ 82	42,284	89	174,980	217,435
Balances (in shares) at Sep. 30, 2014	8,239
Balances at Dec. 31, 2014	$ 83	42,076		174,702	216,861
Balances (in shares) at Dec. 31, 2014	8,346
Increase (Decrease) in Shareholders' Equity
Net income				4,383	4,383
Unrealized loss from derivative instruments, net of tax benefit			(200)		(200)
Shares repurchased	$ (2)	(3,648)			(3,650)
Shares repurchased (in shares)	(208)
Shares issued under stock compensation plans	$ 3	516			519
Shares issued under stock compensation plans (in shares)	207
Cancellation of restricted stock units in satisfaction of withholding tax	$ (1)	(1,100)			(1,101)
Cancellation of restricted stock units in satisfaction of withholding tax (in shares)	(64)
Stock-based compensation, net of forfeitures		2,961			2,961
Tax benefit on disqualified disposition of shares		75			75
Balances at Sep. 30, 2015	$ 83	$ 40,880	$ (200)	$ 179,085	$ 219,848
Balances (in shares) at Sep. 30, 2015	8,281