Legal Proceedings (Textual) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended	3 Months Ended		24 Months Ended
	Mar. 31, 2012 SEC Penalties Settlement [Member]	Mar. 31, 2011 SEC Penalties Settlement [Member]	Mar. 31, 2012 SEC Penalties Settlement [Member]	Mar. 31, 2012 DOJ Penalties Settlement [Member]	Mar. 31, 2011 DOJ Penalties Settlement [Member]	Mar. 31, 2013 DOJ Penalties Settlement [Member]
Loss Contingencies [Line Items]
Total settlement consideration			$ 6.4			$ 8.0
Payments for legal settlements	$ 3.2	$ 3.2		$ 2.3	$ 3.5