Basis of Condensed Consolidated Financial Statements (Details) (USD $) In Millions, except Per Share data, unless otherwise specified			9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Minimum [Member]	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2013 Wells Fargo [Member]	Sep. 30, 2012 Wells Fargo [Member]	Sep. 30, 2013 Wells Fargo [Member]	Sep. 30, 2012 Wells Fargo [Member]
Concentration Risk, Customer					0.099	0.153	0.107	0.116
Common stock, par value	$ 0.00001	$ 0.00001
Escrow deposit	$ 946.7	$ 228.9
Escrow deposits, period held by the Company (in business days)			2 days	5 days