Related Party Transactions (Details 1) (HSBC Finance [Member], USD $) In Billions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Information regarding loans
Loans serviced by HSBC Finance:					$ 21.2
Loans acquired on daily basis from Related Parties	2.5	8.1	9.9	15.5
Private Label Cards [Member]
Information regarding loans
Loans serviced by HSBC Finance:					12.5
Loans acquired on daily basis from Related Parties	1.1	3.6	4.4	6.8
Private Label Commercial and Closed End Loans [Member]
Information regarding loans
Loans serviced by HSBC Finance:					0.3
Credit Card General Motors [Member]
Information regarding loans
Loans serviced by HSBC Finance:					4.1
Loans acquired on daily basis from Related Parties	0.9	3.3	3.9	6.4
Credit Card Union Privilege [Member]
Information regarding loans
Loans serviced by HSBC Finance:					3.5
Loans acquired on daily basis from Related Parties	0.3	0.8	1.0	1.5
Credit Card Other [Member]
Information regarding loans
Loans serviced by HSBC Finance:					0.8
Loans acquired on daily basis from Related Parties	$ 0.2	$ 0.4	$ 0.6	$ 0.8