Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Mar. 31, 2011
Condensed Consolidated Balance Sheets
Accounts receivable, allowances	$ 1,305	$ 1,532
Intangible assets, accumulated amortization	$ 68,296	$ 67,530
Common stock, no par value
Common stock, stated value	$ 0.30	$ 0.30
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	31,606,831	31,606,831
Common stock, shares outstanding	23,001,987	23,022,398
Treasury shares	8,604,844	8,584,433