Employee Benefit Plans - Benefit Obligations in Excess of Plan Assets (Details) $ in Millions	Dec. 31, 2019 USD ($)
Projected Benefit Obligation
Aggregate fair value of plan assets	$ 2,715
Aggregate benefit obligation	(3,037)
Accumulated Benefit Obligation
Aggregate fair value of plan assets	2,715
Aggregate benefit obligation	$ (2,878)

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

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- Definition

Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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-Publisher FASB
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-Publisher FASB
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- Definition

Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
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