Insurance Subsidiaries Purchase of Series A Preferred Stock in Stockholders' Equity (Details) (Series A preferred stock, USD $) In Millions, except Share data, unless otherwise specified			27 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011 Insurance subsidiaries
Insurance investments:
Preferred stock, value, issued			$ 7.2
Preferred stock, shares issued	6,100,000	6,100,000	308,300