Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Mar. 31, 2011
Assets
Allowances for accounts receivable	$ 491	$ 436
Shareholders' equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	30,000,000	30,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, no par value	$ 0	$ 0
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	30,393,053	30,312,758
Common stock, shares outstanding	22,983,886	22,893,803
Treasury stock, shares	7,409,167	7,431,897