Discontinued Operations (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 01, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense		$ 7	$ 14			$ 150	$ 254
Goodwill, impairment loss, net of tax						$ 9
Distributed Earnings Of Foreign Subsidiaries [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Effective income tax rate reconciliation, repatriation of foreign earnings			86
Tropical Shipping [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 225
Income tax expense			$ 29	$ 31			61
Goodwill, impairment loss, net of tax				$ 19
Depreciation and amortization suspension					$ 7
Tropical Shipping [Member] | Distributed Earnings Of Foreign Subsidiaries [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense							$ 60