Securities - Available for Sale Securities Unrealized Losses (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Unrealized Loss And Fair Value Available For Sale Securities [Line Items]
Available for sale securities, Losses less than 12 months, Fair Value	$ 228,780	$ 147,898
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	1,028	248
Available for sale securities, Losses 12 months or longer, Fair value	162,189	212,629
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	2,504	3,891
Available for sale securities, Total, Fair value	390,969	360,527
Available for sale securities, Total, Gross Unrealized Losses	3,532	4,139
Equity Securities [Member]
Unrealized Loss And Fair Value Available For Sale Securities [Line Items]
Available for sale securities, Losses less than 12 months, Fair Value	1,848	5,998
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	6	10
Available for sale securities, Losses 12 months or longer, Fair value	2	3
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	2	1
Available for sale securities, Total, Fair value	1,850	6,001
Available for sale securities, Total, Gross Unrealized Losses	8	11
U.S. Treasury and Government Agency Securities [Member]
Unrealized Loss And Fair Value Available For Sale Securities [Line Items]
Available for sale securities, Losses less than 12 months, Fair Value	99,249	99,950
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	765	70
Available for sale securities, Losses 12 months or longer, Fair value	106	121
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	1	1
Available for sale securities, Total, Fair value	99,355	100,071
Available for sale securities, Total, Gross Unrealized Losses	766	71
Municipal Obligations [Member]
Unrealized Loss And Fair Value Available For Sale Securities [Line Items]
Available for sale securities, Losses less than 12 months, Fair Value		2,995
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses		5
Available for sale securities, Total, Fair value		2,995
Available for sale securities, Total, Gross Unrealized Losses		5
Mortgage-Backed Securities [Member]
Unrealized Loss And Fair Value Available For Sale Securities [Line Items]
Available for sale securities, Losses less than 12 months, Fair Value	23,484	38,955
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	152	163
Available for sale securities, Losses 12 months or longer, Fair value	124,102	125,641
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	1,795	2,660
Available for sale securities, Total, Fair value	147,586	164,596
Available for sale securities, Total, Gross Unrealized Losses	1,947	2,823
Collateralized Mortgage Obligations [Member]
Unrealized Loss And Fair Value Available For Sale Securities [Line Items]
Available for sale securities, Losses less than 12 months, Fair Value	104,199
Available for sale securities, Losses Less than 12 months, Gross Unrealized Losses	105
Available for sale securities, Losses 12 months or longer, Fair value	37,979	86,864
Available for sale securities, Losses 12 months or longer, Gross Unrealized Losses	706	1,229
Available for sale securities, Total, Fair value	142,178	86,864
Available for sale securities, Total, Gross Unrealized Losses	$ 811	$ 1,229

Name:	hbhc_UnrealizedLossAndFairValueAvailableForSaleSecuritiesLineItems
Namespace Prefix:	hbhc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ References

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)(2)

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

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

+ Details

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

- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: 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

+ Details

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

- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

+ References

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

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

+ Details

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

- Definition

+ References

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

+ Details

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

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CollateralizedMortgageObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_MunicipalBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: