Fair Value Measurements (Details) - USD ($)		Sep. 30, 2015	Dec. 31, 2014
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Fair value adjustment to the borrowings subject to TROR		$ 5,077,778,000	$ 5,346,196,000
Fair value measurement, recurring basis [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Fair value adjustment to the borrowings subject to TROR		2,305,000	5,604,000
Redeemable noncontrolling interest	[1]	(168,226,000)	(183,038,000)
Total fair value		(238,087,000)	(271,434,000)
Fair value measurement, recurring basis [Member] | Interest rate caps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets			126,000
Fair value measurement, recurring basis [Member] | Interest rate swaps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative liabilities		(61,096,000)	(75,281,000)
Fair value measurement, recurring basis [Member] | TROR [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets		13,412,000	8,236,000
Derivative liabilities		(24,482,000)	(27,081,000)
Fair Value, Inputs, Level 1 [Member] | Fair value measurement, recurring basis [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Fair value adjustment to the borrowings subject to TROR		0	0
Redeemable noncontrolling interest		0	0
Total fair value		0	0
Fair Value, Inputs, Level 1 [Member] | Fair value measurement, recurring basis [Member] | Interest rate caps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets			0
Fair Value, Inputs, Level 1 [Member] | Fair value measurement, recurring basis [Member] | Interest rate swaps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative liabilities		0	0
Fair Value, Inputs, Level 1 [Member] | Fair value measurement, recurring basis [Member] | TROR [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets		0	0
Derivative liabilities		0	0
Fair Value, Inputs, Level 2 [Member] | Fair value measurement, recurring basis [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Fair value adjustment to the borrowings subject to TROR		0	0
Redeemable noncontrolling interest		0	0
Total fair value		(2,873,000)	(1,619,000)
Fair Value, Inputs, Level 2 [Member] | Fair value measurement, recurring basis [Member] | Interest rate caps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets			126,000
Fair Value, Inputs, Level 2 [Member] | Fair value measurement, recurring basis [Member] | Interest rate swaps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative liabilities		(2,873,000)	(1,745,000)
Fair Value, Inputs, Level 2 [Member] | Fair value measurement, recurring basis [Member] | TROR [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets		0	0
Derivative liabilities		0	0
Fair Value, Inputs, Level 3 [Member] | Fair value measurement, recurring basis [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Fair value adjustment to the borrowings subject to TROR		2,305,000	5,604,000
Redeemable noncontrolling interest	[1]	(168,226,000)	(183,038,000)
Total fair value		(235,214,000)	(269,815,000)
Fair Value, Inputs, Level 3 [Member] | Fair value measurement, recurring basis [Member] | Interest rate caps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets			0
Fair Value, Inputs, Level 3 [Member] | Fair value measurement, recurring basis [Member] | Interest rate swaps [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative liabilities		(58,223,000)	(73,536,000)
Fair Value, Inputs, Level 3 [Member] | Fair value measurement, recurring basis [Member] | TROR [Member]
Financial assets and liabilities and redeemable noncontrolling interests on a recurring basis
Derivative assets		13,412,000	8,236,000
Derivative liabilities		$ (24,482,000)	$ (27,081,000)

[1] Redeemable noncontrolling interest is recorded at historical cost as of the period presented.