Repurchases of Common Shares (Detail) (USD $)	12 Months Ended
	Mar. 31, 2015
Number of Shares	2,488,215
Amount	$ 19,200,393	[1]
2014 Repurchase Plan
Number of Shares	1,913,748
Weighted Average Price Per Share	$ 7.82
Amount	14,961,177	[1]
2015 Repurchase Plan
Number of Shares	574,467
Weighted Average Price Per Share	$ 7.38
Amount	$ 4,239,216	[1]

[1] Amount excludes commission fees.