Income Taxes Income Taxes - Deferred Tax Balances (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Successor [Member]
Assets
Deferred Tax Assets, Tax Loss And Tax Credit Carryforwards	$ 1,690
Deferred Tax Assets, Tax Deferred Expense, Accrued Employee Benefits	1,988
Deferred Tax Assets, Tax Deferred Expense, Other Accruals and Reversals	333
Deferred Tax Assets, Intangible Assets	284
Deferred Tax Assets, Inventory	130
Deferred Tax Assets, Long-Term Debt	109
Deferred Tax Assets, Investments	23
Deferred Tax Assets, Other	260
Deferred Tax Assets, Gross	4,817
Deferred Tax Assets, Valuation Allowance	(1,378)
Deferred Tax Assets, Net of Valuation Allowance	3,439
Liabilities
Deferred Tax Liabilities, Property	1,160
Deferred Tax Liabilities, Tax Deferred Expense, Accrued Employee Benefits	68
Deferred Tax Liabilities, Tax Deferred Expense, Other Accruals and Reversals	39
Deferred Tax Liabilities, Intangible Assets	6,286
Deferred Tax Liabilities, Inventory	597
Deferred Tax Liabilities, Investments	453
Deferred Tax Liabilities, Unrealized Exchange Gains/Losses	71
Deferred Tax Liabilities, Other	121
Deferred Tax Liabilities, Gross	8,795
Deferred Tax Liabilities, Net	$ (5,356)
Predecessor [Member]
Assets
Deferred Tax Assets, Tax Loss And Tax Credit Carryforwards		$ 1,808
Deferred Tax Assets, Tax Deferred Expense, Accrued Employee Benefits		4,529
Deferred Tax Assets, Tax Deferred Expense, Other Accruals and Reversals		617
Deferred Tax Assets, Intangible Assets		210
Deferred Tax Assets, Inventory		163
Deferred Tax Assets, Investments		126
Deferred Tax Assets, Other		257
Deferred Tax Assets, Gross		7,710
Deferred Tax Assets, Valuation Allowance		(1,308)
Deferred Tax Assets, Net of Valuation Allowance		6,402
Deferred Tax Assets, Net		2,883
Liabilities
Deferred Tax Liabilities, Property		742
Deferred Tax Liabilities, Tax Deferred Expense, Accrued Employee Benefits		410
Deferred Tax Liabilities, Tax Deferred Expense, Other Accruals and Reversals		222
Deferred Tax Liabilities, Intangible Assets		1,345
Deferred Tax Liabilities, Inventory		138
Deferred Tax Liabilities, Investments		230
Deferred Tax Liabilities, Unrealized Exchange Gains/Losses		346
Deferred Tax Liabilities, Other		86
Deferred Tax Liabilities, Gross		$ 3,519