Loans and Allowance for Loan Losses - Past Due and Non-accrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	$ 58	$ 316
Non-Accrual	8,849	4,754
Loans held for investment	1,280,615	1,168,797
Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	1,269,546	1,161,992
30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	2,162	1,735
Commercial, financial, and agricultural
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	3,022	982
Loans held for investment	296,323	199,022
Commercial, financial, and agricultural \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	292,873	197,828
Commercial, financial, and agricultural \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	428	212
Residential real estate \| Construction
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	0	0
Loans held for investment	27,188	23,035
Residential real estate \| Construction \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	27,188	22,468
Residential real estate \| Construction \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	0	567
Residential real estate \| Mortgages
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	51	304
Non-Accrual	3,310	2,135
Loans held for investment	250,452	252,643
Residential real estate \| Mortgages \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	245,472	249,516
Residential real estate \| Mortgages \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	1,619	688
Commercial real estate \| Construction
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	959	137
Loans held for investment	85,009	84,998
Commercial real estate \| Construction \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	84,050	84,861
Commercial real estate \| Construction \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	0	0
Commercial real estate \| Mortgages
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	0	0
Non-Accrual	1,521	1,359
Loans held for investment	592,855	576,635
Commercial real estate \| Mortgages \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	591,264	575,140
Commercial real estate \| Mortgages \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	70	136
Installment and other consumer
Aging information for the Company's past due and non-accrual loans
90 Days Past Due And Still Accruing	7	12
Non-Accrual	37	141
Loans held for investment	28,788	32,464
Installment and other consumer \| Current or Less Than 30 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	28,699	32,179
Installment and other consumer \| 30 - 89 Days Past Due
Aging information for the Company's past due and non-accrual loans
Financing receivable, recorded investment, past due	$ 45	$ 132

Amount of financing receivable 90 days or more past due and still accruing.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 80
-URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922355-210448

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of financing receivable on nonaccrual status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447

+ Details

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

- Definition

Amount of financing receivable past due.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 80
-URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922355-210448

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919253-210447

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953401-111524

+ Details

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

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

- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

+ Details

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

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables1To29DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=hwbk_FinancingReceivables30To89DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=hwbk_CommercialFinancialAndAgriculturalPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=hwbk_ResidentialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_MortgagesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=hwbk_InstallmentAndOtherConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: