Commitments: (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Extended lines of credit	Dec. 31, 2013 Extended lines of credit	Mar. 31, 2014 Financing for client purchase agreements	Dec. 31, 2013 Financing for client purchase agreements	Mar. 31, 2014 Financial guarantees	Dec. 31, 2013 Financial guarantees
Commitments, guarantees:
Unused amounts in lines of credit to third-party entities and commitments for future financing to clients			$ 6,103	$ 5,028	$ 1,589	$ 1,769
Guarantor obligations, maximum exposure							45	44
Movement in standard warranty liability
Beginning Balance	376	394
Current period accruals	54	71
Accrual adjustments to reflect actual experience	(3)	9
Charges incurred	(85)	(93)
Ending Balance	$ 342	$ 381