Notes and Bonds Payable - Mortgage Notes (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Debt Instrument [Line Items]
Notes and bonds payable	$ 1,348,459	[1]	$ 1,293,044	[1]
Mortgage notes payable [Member] | 5.000%-7.625% Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgage notes	166,684		225,242
Unaccreted discount	(888)		(2,755)
Notes and bonds payable	$ 165,796		$ 222,487

[1] Level 3 - Fair value derived from valuation techniques in which one of more significant inputs or significant value drivers are unobservable.