Leases - Additional Information Related to Leases (Detail) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Leases [Abstract]
Operating cash flows for operating leases (millions)	$ 3
Operating leases (millions)	$ 11
Weighted average remaining lease term (years)	48 years
Weighted average discount rate - operating leases	4.30%

No definition available.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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-Publisher FASB
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+ Details

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

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