Significant accounting policies.

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	Jan. 02, 2019	Sep. 30, 2019	Jan. 01, 2019
Significant Accounting Policies [Line Items]
Right-of-use assets		$ 549
Lease liabilities		$ 558
ASU 2016-02
Significant Accounting Policies [Line Items]
Lease liabilities			$ 628
ASU 2016-02 \| Asset
Significant Accounting Policies [Line Items]
Right-of-use assets			$ 619
ASU 2016-02 \| Rent Liability
Significant Accounting Policies [Line Items]
Reduction of the rent liability due to adoption	$ 9
Host L.P.
Significant Accounting Policies [Line Items]
Percentage of the common OP units		99.00%