Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013 Lease
Commitments and Contingencies [Abstract]
Number of non cancelable ground leases	6
Operating Leases, Future Minimum Payments Due [Abstract]
Due by September 20, 2014	$ 1.7
September 30, 2015	1.7
September 30, 2016	1.7
September 30, 2017	1.7
September 30, 2018	1.7
Payment Guarantee [Member] \| Construction Contracts [Member]
Guarantor Obligations [Line Items]
Maximum exposure of the guarantee	$ 88.9

Number of non-cancelable ground leases.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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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.

+ References

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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.

+ References

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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.

+ References

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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.

+ References

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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.

+ References

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