Name:	husi_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionGreaterThan12MonthsAggregateLossesAccumulatedInInvestments
Namespace Prefix:	husi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Available-for-sale Securities Continuous Unrealized Loss Position Less Than 12 Months Aggregate Losses Accumulated In Investments

No definition available.

Name:	husi_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesAccumulatedInInvestments
Namespace Prefix:	husi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Available for sale securities continuous unrealized loss position less than twelve months number of securities.

No definition available.

Name:	husi_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsNumberOfSecurities
Namespace Prefix:	husi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Available for sale securities continuous unrealized loss position twelve months or longer number of securities.

No definition available.

Name:	husi_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerNumberOfSecurities
Namespace Prefix:	husi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Held-to-maturity Securities Continuous Unrealized Loss Position 12 Months Or Longer Accumulated Loss

No definition available.

Name:	husi_HeldtomaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix:	husi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Held to Maturity Securities Continuous Unrealized Loss Position Less Than 12 Months Accumulated Loss

No definition available.

Name:	husi_HeldtoMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix:	husi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Held to maturity securities continuous unrealized loss position less than twelve months number of securities.

No definition available.

Name:	husi_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsNumberOfSecurities
Namespace Prefix:	husi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Held to maturity securities continuous unrealized loss position twelve months or longer number of securities.

No definition available.

Name:	husi_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerNumberOfSecurities
Namespace Prefix:	husi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

Name:	us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Name:	us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents the fair value of securities categorized as held-to-maturity that have been in a continuous unrealized loss position for less than twelve months.

Name:	us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents the fair value of securities categorized as held-to-maturity securities that have been in a continuous unrealized loss position for twelve months or longer.