Impairment Charges and Impairment of Joint Venture Investments - Impairment Charges Measured at Fair Value on Non-Recurring Basis (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of joint venture investments	$ 0	$ 1,909	$ 30,652
Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unconsolidated joint venture investments, Fair Value Measurements		0	6,400
Long-lived assets held and used/held for sale, Fair Value Measurements	438,200	407,100	141,200
Long-lived assets held and used/held for sale, Total Losses	110,900	279,000	38,100
Impairment of joint venture investments		1,900	30,700
Fair Value Measurements [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held and used/held for sale, Fair Value Measurements	0	0	0
Unconsolidated joint venture investments, Fair Value Measurements		0	0
Fair Value Measurements [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held and used/held for sale, Fair Value Measurements	0	0	0
Unconsolidated joint venture investments, Fair Value Measurements		0	0
Fair Value Measurements [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets held and used/held for sale, Fair Value Measurements	$ 438,200	407,100	141,200
Unconsolidated joint venture investments, Fair Value Measurements		$ 0	$ 6,400