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Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lessee Lease Description [Line Items]
Operating lease weighted average remaining term	3 years
Finance lease weighted average remaining term	5 years
Operating lease weighted-average discount rates	6.10%
Finance lease weighted-average discount rates	5.60%
Rental expense		$ 48	$ 50
Total future lease commitments	$ 60
Series of Individually Immaterial Business Acquisitions [Member]
Lessee Lease Description [Line Items]
Rental expense	2	$ 3	$ 3
Total future lease commitments	$ 1
Operating leases, expiry year	2020

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- Definition

Operating leases, expiry year.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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- Definition

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

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- Definition

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

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- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

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-Publisher FASB
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