Allowance of credit losses from expansion loss horizon of life of loan.

No definition available.

Name:	hth_AllowanceOfCreditLossesExpansionLossHorizonOfLifeOfLoan
Namespace Prefix:	hth_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents amount of elimination of allowance of the non-credit component within the allowance of previously categorized purchase credit impairment loans.

+ References

No definition available.

+ Details

Name:	hth_EliminationNoncreditComponentOfPreviouslyCategorizedWithPurchaseCreditImpairment
Namespace Prefix:	hth_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Increase (decrease) in valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

No definition available.

+ Details

Name:	hth_FinancingReceivableIncreaseDecreaseAllowanceForCreditLossesCollectivelyEvaluatedForImpairment
Namespace Prefix:	hth_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Increase (decrease) in valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

No definition available.

+ Details

Name:	hth_FinancingReceivableIncreaseDecreaseAllowanceForCreditLossesIndividuallyEvaluatedForImpairment
Namespace Prefix:	hth_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesWriteoffsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

+ Details

Name:	us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RestatementAxis=srt_RestatementAdjustmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loans Held for Investment - Credit Loss Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Allowance for loan losses
Allowance for credit losses	$ 156,383	$ 156,383	$ 106,739	$ 61,136	$ 55,177	$ 58,809	$ 59,486
Increase in allowance on individually evaluated loans	6,200	23,800
Increase in allowance on collectively evaluated loans	59,900	76,600
Allowance for Loan and Lease Losses Write-offs, Net	$ 16,400	$ 17,900
ASU 2016-13
Allowance for loan losses
Allowance for credit losses				73,700
ASU 2016-13 \| Restatement
Allowance for loan losses
Allowance for credit losses				12,562
Allowance in credit loss from expansion of horizon to life of loan				18,900
Non-credit component with allowance of previous categorized PCI loans				$ 6,300