Shareholders Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2012	Aug. 31, 2011
Changes in shareholders' equity accounts
Beginning Balance, Amount			$ 359,875
Beginning Balance, Shares			30,053,443
Beginning Balance, Treasury Stock, Shares			(4,129,668)
Net earnings	7,592	9,712	11,471	21,136
Foreign currency translation, net of deferred tax of $526	1,257	(827)	(850)	131
Dividends declared ($.35 per share)			(9,135)
Stock based compensation			697
Exercise of stock options and restricted stock grants			26
Stock repurchases			(2)
Stock repurchases shares			(175)
Ending Balance, Treasury Stock, Shares	(4,090,265)		(4,090,265)
Ending Balance, Amount	362,082		362,082
Ending Balance, Shares	30,053,443		30,053,443
Common Stock [Member]
Changes in shareholders' equity accounts
Beginning Balance, Amount			75,134
Beginning Balance, Shares			30,053,443
Net earnings
Foreign currency translation, net of deferred tax of $526
Dividends declared ($.35 per share)
Stock based compensation
Exercise of stock options and restricted stock grants
Exercise of stock options and restricted stock grants shares
Stock repurchases
Stock repurchases shares
Ending Balance, Amount	75,134		75,134
Ending Balance, Shares	30,053,443		30,053,443
Additional Paid-in Capital [Member]
Changes in shareholders' equity accounts
Beginning Balance, Amount			121,390
Net earnings
Foreign currency translation, net of deferred tax of $526
Dividends declared ($.35 per share)
Stock based compensation			697
Exercise of stock options and restricted stock grants			(680)
Stock repurchases
Ending Balance, Amount	121,407		121,407
Retained Earnings [Member]
Changes in shareholders' equity accounts
Beginning Balance, Amount			249,862
Net earnings			11,471
Foreign currency translation, net of deferred tax of $526
Dividends declared ($.35 per share)			(9,135)
Stock based compensation
Exercise of stock options and restricted stock grants
Stock repurchases
Ending Balance, Amount	252,198		252,198
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in shareholders' equity accounts
Beginning Balance, Amount			(12,785)
Net earnings
Foreign currency translation, net of deferred tax of $526			(850)
Dividends declared ($.35 per share)
Stock based compensation
Exercise of stock options and restricted stock grants
Stock repurchases
Ending Balance, Amount	(13,635)		(13,635)
Treasury Stock [Member]
Changes in shareholders' equity accounts
Beginning Balance, Amount			(73,726)
Beginning Balance, Treasury Stock, Shares			(4,129,668)
Net earnings
Foreign currency translation, net of deferred tax of $526
Dividends declared ($.35 per share)
Stock based compensation
Exercise of stock options and restricted stock grants			706
Exercise of stock options and restricted stock grants shares			39,578
Stock repurchases			(2)
Stock repurchases shares			(175)
Ending Balance, Treasury Stock, Shares	(4,090,265)		(4,090,265)
Ending Balance, Amount	$ (73,022)		$ (73,022)