Commitments and contingencies Future Minimum Lease Obligations Schedule (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Office Leases
2014	$ 1,324
2015	1,394
2016	1,468
2017	1,542
2018	1,617
Thereafter	1,482
Total	8,827
Ground Leases
2014	10,520
2015	9,900
2016	10,504
2017	10,572
2018	10,662
Thereafter	635,289
Total	687,447
Total
2014	11,844
2015	11,294
2016	11,972
2017	12,114
2018	12,279
Thereafter	636,771
Total	$ 696,274

Represents the aggregate amount of ground and operating lease obligation due.

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Represents the aggregate amount of ground and operating lease obligation due after the fifth year from the balance sheet date.

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No definition available.

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Represents the aggregate amount of ground and operating lease obligation due in the fifth year from the balance sheet date.

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Represents the aggregate amount of ground and operating lease obligation due in the fourth year from the balance sheet date.

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No definition available.

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Represents the aggregate amount of ground and operating lease obligation due in the second year from the balance sheet date.

+ References

No definition available.

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Represents the aggregate amount of ground and operating lease obligation due in the third year from the balance sheet date.

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No definition available.

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Represents the aggregate amount of ground and operating lease obligation due in the first year from the balance sheet date.

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No definition available.

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Represents the aggregate amount of ground lease obligation due.

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Represents the aggregate amount of ground lease obligation due beyond the fifth year after the balance sheet date.

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No definition available.

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Represents the aggregate amount of ground lease obligation due in the fifth year after the balance sheet date.

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Represents the aggregate amount of ground lease obligation due in the fourth year after the balance sheet date.

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No definition available.

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Represents the aggregate amount of ground lease obligation due in the second year after the balance sheet date.

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Represents the aggregate amount of ground lease obligation due in the third year after the balance sheet date.

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Represents the aggregate amount of ground lease obligation due in the first year after the balance sheet date.

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No definition available.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 122

-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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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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