Fair Value Option - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Cumulative increased value of debt through fair value option adjustments	$ 311	$ 386

Cumulative Increased Value of Debt through Fair Value Option Adjustments

No definition available.

Name:	hsbcfc_CumulativeIncreasedValueOfDebtThroughFairValueOptionAdjustments
Namespace Prefix:	hsbcfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant