Earnings Per Share - Components of Denominator for Basic Earnings Per Common Share and Diluted Earnings Per Common Share (Detail) (Parenthetical)	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Options excluded from the computation of diluted earnings per share	419,500	99,000	278,167	214,000