Long-Term Debt - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2015	Sep. 30, 2015
Debt Instrument [Line Items]
Cumulative carrying value adjustments on derivative financial instruments	$ 15,000,000	$ 8,000,000
Change in carrying value of foreign debt resulting from translation adjustments	347,000,000	189,000,000
Long-term debt carried at fair value	3,257,000,000	6,762,000,000
Interest Expense for long-term debt for continuing operations	$ 688,000,000	$ 836,000,000	$ 1,141,000,000
Weighted average interest rate on long-term debt	4.77%	4.69%
Long-term debt collateralized by receivables	$ 879,000,000	$ 1,489,000,000
Loans pledged as collateral	1,654,000,000	2,999,000,000
Junior subordinated notes issued to capital trusts [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	1,031,000,000
Revolving Credit Facility [Member] | HSBC North America [Member]
Debt Instrument [Line Items]
Borrowing capacity of credit facility		$ 455,000,000		$ 1,000,000,000	$ 1,000,000,000