Investment in Lease Financing (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable
Rental receivable, net of principal and interest on nonrecourse debt	$ 3,589		$ 3,556
Estimated residual value of leased assets	779		754
Initial direct cost, net of amortization	17		15
Gross investment in lease financing	4,385		4,325
Unearned income	(665)		(700)
Net investment in lease financing	$ 3,720	[1]	$ 3,625	[1]

[1] The accumulated allowance for uncollectible minimum lease payments was $45 million and $53 million at December 31, 2014 and 2013, respectively