Related Party Transactions - Schedule of due to Affiliated entities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Due to affiliates	$ 6,945	$ 6,945
Due to affiliate, carried at fair value	513	512
HSBC Private Banking Holdings (Suisse) S.A and subsidiaries [Member]
Related Party Transaction [Line Items]
Due to affiliates	2,500	2,500
HSBC USA, Inc. [Member]
Related Party Transaction [Line Items]
Due to affiliates	3,012	3,012
HSBC Holdings pcl [Member]
Related Party Transaction [Line Items]
Due to affiliates	833	833
HSBC North America [Member]
Related Party Transaction [Line Items]
Due to affiliates	$ 600	$ 600