Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Effective tax rate	19.00%	37.00%
Provision for income taxes	$ 22	$ 96
Provision for income taxes at U.S. federal statutory tax rate	21.00%	35.00%
Tax Cuts and Jobs Act, Accounting Complete	true
Provisional deemed repatriation tax	$ 10
Deferred tax assets	1,900		$ 1,600
Net deferred income tax liability	$ 5,300		$ 5,300

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Tax cuts and jobs act of 2017 change in tax rate income tax expense benefit deemed repatriation tax provisional.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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