Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 55
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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

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Pension, Post-Retirement and Post-Employment Plans - Domestic Defined Benefit Pension Plan (Details) - Pension Plan - Domestic - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans
Projected benefit obligation	$ 230	$ 220
Liability-Matching
Defined Benefit Plans and Other Postretirement Benefit Plans
Plan investment mix (percent)	90.00%
Long Term Growth
Defined Benefit Plans and Other Postretirement Benefit Plans
Plan investment mix (percent)	8.00%
Near Term Benefit Payments
Defined Benefit Plans and Other Postretirement Benefit Plans
Plan investment mix (percent)	2.00%
Limited Partnership Interests and Managed Funds
Defined Benefit Plans and Other Postretirement Benefit Plans
Weighted average asset allocation (percent)	55.00%
Fixed Income Holdings
Defined Benefit Plans and Other Postretirement Benefit Plans
Weighted average asset allocation (percent)	34.00%
Equity Securities
Defined Benefit Plans and Other Postretirement Benefit Plans
Weighted average asset allocation (percent)	9.00%
Cash
Defined Benefit Plans and Other Postretirement Benefit Plans
Weighted average asset allocation (percent)	2.00%