Leases - Additional Information (Detail) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($) GroundLease
Lessee Lease Description [Line Items]
Number of ground leases \| GroundLease	23
Financial leases	$ 1
Liabilities held for sale	38
Lease Liabilities Undiscounted Cash Flows	$ 1,705
Ground Leases
Lessee Lease Description [Line Items]
Percentage of 2019 minimum lease payments	80.00%
Percentage of total future minimum lease payments	99.00%
Lease Liabilities Undiscounted Cash Flows	$ 1,687
Ground Leases \| Sheraton San Diego Hotel & Marina
Lessee Lease Description [Line Items]
Liabilities held for sale	38
Lease Liabilities Undiscounted Cash Flows	$ 130
Ground Leases \| Minimum
Lessee Lease Description [Line Items]
Discount rates	4.30%
Ground Leases \| Minimum \| IBR
Lessee Lease Description [Line Items]
LIBOR swap rates, terms used to calculate IBR	1 year
Ground Leases \| Maximum
Lessee Lease Description [Line Items]
Discount rates	5.70%
Ground Leases \| Maximum \| IBR
Lessee Lease Description [Line Items]
LIBOR swap rates, terms used to calculate IBR	50 years
Office Leases \| Bethesda
Lessee Lease Description [Line Items]
Lease expiration date	2022
Office Leases \| Miami
Lessee Lease Description [Line Items]
Lease expiration date	2022
Office Leases \| San Diego
Lessee Lease Description [Line Items]
Lease expiration date	2021

Lease expiration year.

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- Definition

London Interbank Offered Rate swap rates terms used to calculate incremental borrowing rate.

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- Definition

Percentage of current fiscal year minimum lease payments.

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- Definition

Percentage of future minimum lease payments.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Discount rate used by lessee to determine present value of operating lease payments.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease.

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- Definition

Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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- Definition

Number of separate real estate development properties located on land subject to ground leases.

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