Components Of Vehicle Depreciation And Lease Charges (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Vehicle Depreciation and Lease Charges, Net [Line Items]
Depreciation expense	$ 1,837	$ 1,840	$ 1,678
Lease charges	156	163	139
Gain on sale of vehicles, net	(60)	(7)	(6)
Vehicle depreciation and lease charges, net	1,933	1,996	1,811
Accounts Payable, Other, Current	269	222	260
Receivables due from former subsidiaries	$ 433	$ 352	$ 378

Carrying value as of the balance sheet date of obligations incurred and payable, which are not elsewhere specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Liabilities
-URI http://asc.fasb.org/extlink&oid=6509677

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