Acceptable tolerance limit of investment allocations for securities.

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Pension And Postretirement Benefits

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Defined plan benefit obligation.

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Pension and Other Postretirement Benefits Disclosure [Line Items]

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement.

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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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.

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The amount of plan compensation cost recognized during the period.

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Amount of increase (decrease) in obligation for pension benefits. Includes, but is not limited to, defined benefit or defined contribution plans. Excludes other postretirement benefits.

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Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits.

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Pension Plans, Postretirement and Other Employee Benefits - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Oct. 01, 2018
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expense recorded relating to employee matching contribution			$ 43	$ 29	$ 28
Decrease in pension obligations	$ 66
Increase in AOCI	51		51
Increase in AOCI, net of tax	16		$ 16
Lump sum payments		$ 18		10
Non-cash charge		$ 72		6
Acceptable tolerance limit of investment allocations for securities			5.00%
Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Accumulated benefit obligation	2,225		$ 2,225	728
Other Postretirement Benefits Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected contributions in 2019	28		28
Pension benefit obligations	$ 75		$ 75	$ 9
U.S.
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	49.00%		49.00%
U.S. \| Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected contributions in 2019	$ 26		$ 26
Expected long-term return on plan assets			6.00%	7.75%	7.60%
U.S. \| Equity securities
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	60.00%		60.00%
U.S. \| Fixed income securities
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	15.00%		15.00%
U.S. \| Debt Securities
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	15.00%		15.00%
U.S. \| Other
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	10.00%		10.00%
Non-U.S. \| Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected contributions in 2019	$ 42		$ 42
Expected long-term return on plan assets			4.20%	5.25%	5.70%
Federal-Mogul
Pension and Other Postretirement Benefits Disclosure [Line Items]
Pension and postretirement benefits acquired	$ 848		$ 848			$ 879