Derivative And Hedging Instruments (Schedule Of Terms Of Interest Rate Cap Agreements) (Details) - USD ($)		Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Debt financing amount		$ 2,086,300,000	$ 1,752,500,000
Interest rate swap agreements outstanding		100,000
Warehouse Facility II [Member]
Derivative [Line Items]
Debt financing amount	[1],[2]	400,000,000
Warehouse Facility II [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Debt financing amount		400,000,000	325,000,000
Notional value		$ 325,000,000	$ 325,000,000
Cap Interest Rate	[3]	5.50%	5.50%
Warehouse Facility IV [Member]
Derivative [Line Items]
Debt financing amount	[1],[2]	$ 75,000,000
Warehouse Facility IV [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Debt financing amount		75,000,000	$ 75,000,000.0
Notional value		$ 75,000,000	$ 29,300,000
Cap Interest Rate	[3]	5.50%	5.50%
Warehouse Facility IV Member Starting March 2014 [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Notional value			$ 45,700,000
Cap Interest Rate	[3]		5.50%
Warehouse Facility IV Member Starting March 2014 [Member] | 5.00% Cap Interest Rate [Member]
Derivative [Line Items]
Cap Interest Rate	[3]		5.00%
Warehouse Facility V [Member]
Derivative [Line Items]
Debt financing amount	[1],[2]	$ 100,000,000
Warehouse Facility V [Member] | 5.50% Cap Interest Rate [Member]
Derivative [Line Items]
Debt financing amount		100,000,000
Notional value		$ 75,000,000	$ 56,300,000
Cap Interest Rate	[3]	5.50%
Warehouse Facility V [Member] | 5.00% Cap Interest Rate [Member]
Derivative [Line Items]
Debt financing amount			$ 75,000,000.0

[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 or the commercial paper rate, as applicable.