Receivables - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended			1 Months Ended
	Mar. 30, 2012	Dec. 31, 2013 Agreement	Dec. 31, 2012	May 31, 2013 Institution	Mar. 31, 2012 Minimum [Member]	May 31, 2013 Maximum [Member]	Mar. 31, 2012 Maximum [Member]
Schedule Of Financial Receivables [Line Items]
Funding of customer receivables sold					$ 50		$ 250
Funding of customer receivables sold after amendment						500
Sale of customer receivables	304
Cash received for receivables	50
Deferred purchase price receivable	254
Number of additional financial institution				2,000,000
Additional funding received		5	155
Amount of cash draws under arrangement		388	160
Amount of cash repayments under arrangement		383	5
Purchase price receivable		248	18
Gross cash outflows from deferred purchased receivables		6,985	3,339
Gross cash inflows from deferred purchased receivables		6,755	3,321
Accounts receivables		10,324
Cash collections		9,866
Number of arrangement with different financial institution to sell customer receivables		3
Asset servicing value		0
Liability servicing value		$ 0