Loans - Loans by Class Modified as Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) Loan	Jun. 30, 2018 USD ($) Loan	Jun. 30, 2019 USD ($) Loan	Jun. 30, 2018 USD ($) Loan
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	5	3	6
Pre-Modification Outstanding Recorded Investment	$ 864	$ 634	$ 1,199	$ 758
Post-Modification Recorded Investment	$ 868	$ 660	$ 1,223	$ 784
Commercial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1		1	1
Pre-Modification Outstanding Recorded Investment	$ 824		$ 824	$ 124
Post-Modification Recorded Investment	$ 824		$ 824	$ 124
Commercial Loans [Member] \| Nonresidential [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan				1
Pre-Modification Outstanding Recorded Investment				$ 124
Post-Modification Recorded Investment				$ 124
Commercial Loans [Member] \| Secured [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1		1
Pre-Modification Outstanding Recorded Investment	$ 824		$ 824
Post-Modification Recorded Investment	$ 824		$ 824
Residential Mortgage Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan		3	1	3
Pre-Modification Outstanding Recorded Investment		$ 521	$ 335	$ 521
Post-Modification Recorded Investment		$ 547	$ 355	$ 547
Residential Mortgage Loans [Member] \| One-to Four-Family [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan		3	1	3
Pre-Modification Outstanding Recorded Investment		$ 521	$ 335	$ 521
Post-Modification Recorded Investment		$ 547	$ 355	$ 547
Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1	2	1	2
Pre-Modification Outstanding Recorded Investment	$ 40	$ 113	$ 40	$ 113
Post-Modification Recorded Investment	$ 44	$ 113	$ 44	$ 113
Consumer Loans [Member] \| Home Equity [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1	2	1	2
Pre-Modification Outstanding Recorded Investment	$ 40	$ 113	$ 40	$ 113
Post-Modification Recorded Investment	$ 44	$ 113	$ 44	$ 113

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.

No definition available.

+ Details

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ConsumerLoanMember
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: