Financing Receivables: (Details 6) (Global Financing, Financing Receivable Portfolio)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Financial Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	38.00%	38.00%
Government Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	15.00%	16.00%
Manufacturing Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	14.00%	14.00%
Retail Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	8.00%	9.00%
Services Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	7.00%	7.00%
Healthcare Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	6.00%	6.00%
Communications Industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	7.00%	6.00%
Other industries
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables (as a percent)	4.00%	4.00%