Condensed Consolidated Statements Of Shareholders' Equity (unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Balances, shares at Dec. 31, 2018		41,357
Shares repurchased and retired, shares		(2,383)
Stock options exercised, shares		13
Vesting of restricted stock units, shares		227
Shares withheld for taxes, shares		(45)
Balances, shares at Mar. 31, 2019		39,169
Beginning Balances, value at Dec. 31, 2018	$ 1,132,225	$ 4,136	$ 554,939	$ 584,274	$ (11,124)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	2,772	0	2,772	0	0
Shares repurchased and retired, value	(61,080)	(239)	(26,473)	(34,368)	0
Stock options exercised, value	279	1	278	0	0
Vesting of restricted stock units, value	0	23	(23)	0	0
Shares withheld for taxes, value	(1,236)	(4)	(1,232)	0	0
Dividends declared	(5,875)	0	0	(5,875)	0
Net income	13,773	0	0	13,773	0
Other comprehensive loss	(2,133)	0	0	0	(2,133)
Ending Balances, value at Mar. 31, 2019	$ 1,078,725	$ 3,917	530,261	557,804	(13,257)
Balances, shares at Dec. 31, 2019	36,957	36,957
Shares repurchased and retired, shares		(724)
Stock options exercised, shares		16
Vesting of restricted stock units, shares		236
Shares withheld for taxes, shares		(70)
Balances, shares at Mar. 31, 2020	36,415	36,415
Beginning Balances, value at Dec. 31, 2019	$ 1,014,832	$ 3,696	512,019	515,876	(16,759)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	2,739	0	2,739	0	0
Shares repurchased and retired, value	(19,329)	(73)	(8,048)	(11,208)	0
Stock options exercised, value	359	2	357	0	0
Vesting of restricted stock units, value	0	24	(24)	0	0
Shares withheld for taxes, value	(1,767)	(7)	(1,760)	0	0
Dividends declared	(5,828)	0	0	(5,828)	0
Net income	3,852	0	0	3,852	0
Other comprehensive loss	(5,236)	0	0	0	(5,236)
Ending Balances, value at Mar. 31, 2020	$ 989,622	$ 3,642	$ 505,283	$ 502,692	$ (21,995)