Commitments and Contingencies Commitments and Contingencies (Ground Rent) (Details) (Ground Rent [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Ground Rent [Member]
Long-term Purchase Commitment [Line Items]
2013 (nine months remaining)	$ 1,364
2014	1,818
2015	1,818
2016	1,909
2017	1,909
Thereafter	$ 288,297

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Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph b(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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+ References

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+ References

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- Definition

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+ References

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