Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares shares in Thousands	Dec. 31, 2018	Mar. 31, 2018
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	20,000	20,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000	300,000
Common stock, shares issued (in shares)	176,369	176,369
Common stock, shares outstanding (in shares)	168,795	168,434
Treasury stock, shares (in shares)	7,574	7,935