Dispositions and Held-for-Sale (Sales Leaseback) (Details) - Commercial Property In San Francisco $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
Sale and leaseback transaction
Sales price	$ 120.6
Net book value	31.6
Pre-tax profit from sale	85.4
Selling costs	3.6
Current period gain recognized	71.7
Deferred gain	$ 13.7

The portion of the deferred gain that was recognized in the current period.

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The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

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The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

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Amount of cash inflow before closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in investing activities.

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The net book value of the asset(s) sold in connection with the sale of the property to another party and lease back to the seller.

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Amount of cash outflow for transaction costs in a sale-leaseback recognized in investing activities. Includes, but is not limited to, closing and debt issuance costs.

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