Other Assets and Other Liabilities - Schedule of Amortized Rental Income (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Intangible Lease Assets Future Amortization Expense [Line Items]
Amortization Expense 2013	$ 71,246
Amortization Expense 2014	52,987
Amortization Expense 2015	39,423
Amortization Expense 2016	23,109
Amortization Expense 2017	12,570
Amortization Expense Thereafter	19,171
Amortization Expense Totals	218,506
2013	56,289
2014	67,937
2015	48,360
2016	29,254
2017	23,369
Thereafter	71,136
Totals	$ 296,345