Loans - Impaired Loans with Associated Allowance (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Unpaid principal balance
With no related allowance	$ 7,158	$ 10,386
With an allowance	4,983	6,566
Total individually evaluated impaired loans	12,141	16,952
Recorded investment
With no related allowance	7,005	10,180
With an allowance	3,773	5,886
Total individually evaluated impaired loans	10,778	16,066
Specific reserves	3,139	4,107
Financing receivable, nonaccrual status	8,802	12,060
SBA loans held for investment
Unpaid principal balance
With no related allowance	414	1,799
With an allowance	460	434
Total individually evaluated impaired loans	874	2,233
Recorded investment
With no related allowance	313	1,698
With an allowance	207	404
Total individually evaluated impaired loans	520	2,102
Specific reserves	161	324
Financing receivable, nonaccrual status	660	2,473
Commercial loans
Unpaid principal balance
With no related allowance	1,716	1,462
With an allowance	3,809	4,890
Total individually evaluated impaired loans	5,525	6,352
Recorded investment
With no related allowance	1,716	1,462
With an allowance	2,852	4,240
Total individually evaluated impaired loans	4,568	5,702
Specific reserves	2,811	3,682
Commercial loans \| Commercial real estate
Unpaid principal balance
With no related allowance	1,716	1,462
With an allowance	986	1,730
Total individually evaluated impaired loans	2,702	3,192
Recorded investment
With no related allowance	1,716	1,462
With an allowance	139	1,080
Total individually evaluated impaired loans	1,855	2,542
Specific reserves	139	576
Financing receivable, nonaccrual status	785	1,059
Commercial loans \| Consumer other
Unpaid principal balance
With an allowance	2,823	3,160
Total individually evaluated impaired loans	2,823	3,160
Recorded investment
With an allowance	2,713	3,160
Total individually evaluated impaired loans	2,713	3,160
Specific reserves	2,672	3,106
Financing receivable, nonaccrual status	2,094	266
Residential mortgage loans
Unpaid principal balance
With no related allowance	2,391	4,080
With an allowance	287	1,242
Total individually evaluated impaired loans	2,678	5,322
Recorded investment
With no related allowance	2,339	3,975
With an allowance	287	1,242
Total individually evaluated impaired loans	2,626	5,217
Specific reserves	30	101
Financing receivable, nonaccrual status	2,626	5,217
Consumer loans
Recorded investment
Total individually evaluated impaired loans	427
Consumer loans \| Home equity
Unpaid principal balance
With no related allowance		1,295
With an allowance	427
Total individually evaluated impaired loans	427	1,295
Recorded investment
With no related allowance		1,295
With an allowance	427
Total individually evaluated impaired loans	427	1,295
Specific reserves	137
Financing receivable, nonaccrual status		1,295
Residential construction loans
Unpaid principal balance
With no related allowance	2,637	1,750
Total individually evaluated impaired loans	2,637	1,750
Recorded investment
With no related allowance	2,637	1,750
Total individually evaluated impaired loans	2,637	1,750
Financing receivable, nonaccrual status	2,637	1,750
Collateral Pledged \| Small Business Administration
Recorded investment
Financing receivable, nonaccrual status	$ 139	$ 371

Amount of financing receivable on nonaccrual status.

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=121611835&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=121599337&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 investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

+ Details

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

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

+ Details

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

- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

+ Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_CollateralAxis=us-gaap_CollateralPledgedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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