Related Party Transactions - Information Regarding Loans (Details) (HSBC Finance [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Revenue from External Customer [Line Items]
Loans acquired on daily basis from Related Parties	$ 7,400
Private Label Cards [Member]
Revenue from External Customer [Line Items]
Loans acquired on daily basis from Related Parties	3,300
Private Label Commercial and Closed End Loans [Member]
Revenue from External Customer [Line Items]
Loans acquired on daily basis from Related Parties	0
Credit Card General Motors [Member]
Revenue from External Customer [Line Items]
Loans acquired on daily basis from Related Parties	2,900
Credit Card Union Privilege [Member]
Revenue from External Customer [Line Items]
Loans acquired on daily basis from Related Parties	700
Credit Card Other [Member]
Revenue from External Customer [Line Items]
Loans acquired on daily basis from Related Parties	$ 500