Consolidated Balance Sheets (Parenthetical) - shares	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017
Common Stock [Member]
Common stock, shares authorized	100,000,000	100,000,000	100,000,000
Common stock, shares issued	24,968,799	24,930,725	25,114,349
Common stock, shares outstanding	24,968,799	24,930,725	25,114,349
Series A Junior Participating Preferred Stock [Member]
Preferred stock, shares authorized	500,000	500,000	500,000
Preferred stock, shares issued	0	0	0
Preferred stock, shares outstanding	0	0	0