Derivative and Hedging Instruments (Schedule of Terms of Interest Rate Cap Agreements) (Details) - USD ($)		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Derivative [Line Items]
Debt facility financing amount		$ 2,345,600,000		$ 2,086,300,000
Interest rate caps, fair value of less than $0.1 million		100,000		100,000
Warehouse Facility II [Member]
Derivative [Line Items]
Debt facility financing amount	[1],[2]	400,000,000
Warehouse Facility II [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Debt facility financing amount		$ 400,000,000		400,000,000
Start		Dec. 01, 2014	Dec. 01, 2014
End		Jun. 01, 2016	Jun. 01, 2016
Notional		$ 325,000,000		$ 325,000,000
Cap Interest Rate	[3]	5.50%		5.50%
Warehouse Facility IV [Member]
Derivative [Line Items]
Debt facility financing amount	[1],[2]	$ 75,000,000
Warehouse Facility IV [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Debt facility financing amount		$ 75,000,000		$ 75,000,000
Start		Mar. 01, 2014	Mar. 01, 2014
End		Mar. 01, 2017	Mar. 01, 2017
Notional		$ 75,000,000		$ 75,000,000
Cap Interest Rate	[3]	5.50%		5.50%
Warehouse Facility V [Member]
Derivative [Line Items]
Debt facility financing amount	[1],[2]	$ 100,000,000
Warehouse Facility V [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Debt facility financing amount		$ 100,000,000		$ 100,000,000
Start		Jun. 01, 2015	Jun. 01, 2015
End		Jul. 01, 2018	Jul. 01, 2018
Notional		$ 75,000,000		$ 75,000,000
Cap Interest Rate	[3]	5.50%		5.50%

[1] Financing made available only to a specified subsidiary of the Company.

[2] Interest rate cap agreements are in place to limit the exposure to increasing interest rates.

[3] Rate excludes the spread over the LIBOR rate.