Income Taxes (Details)	6 Months Ended
	Sep. 30, 2012
U.S. federal [Member] | Maximum [Member]
Summary of open tax years
Open tax years	2011
U.S. federal [Member] | Minimum [Member]
Summary of open tax years
Open tax years	2008
States [Member] | Maximum [Member]
Summary of open tax years
Open tax years	2011
States [Member] | Minimum [Member]
Summary of open tax years
Open tax years	2007