Notes and Bonds Payable (Details 2) (Senior Notes Due 2017 [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Senior Notes Due 2017 [Member]
Reconciliation of Senior Notes due 2017
Mortgage notes	$ 300,000	$ 300,000
Unaccreted discount	(1,406)	(1,535)
Senior Notes, carrying amount	$ 298,594	$ 298,465

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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