Share-based Compensation Arrangement by Share-based Payment Award Available for Grant [Roll Forward]

No definition available.

Name:	ufcs_ShareBasedCompensationArrangementByShareBasedPaymentAwardAvailableForGrantRollForward
Namespace Prefix:	ufcs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of share-based compensation awards forfeited or expired in Period

+ References

No definition available.

+ Details

Name:	ufcs_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeituresAndExpirationInPeriod
Namespace Prefix:	ufcs_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Grants in Period, Gross

+ References

No definition available.

+ Details

Name:	ufcs_ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantsInPeriodGross
Namespace Prefix:	ufcs_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_PlanNameAxis=ufcs_EmployeeStockAwardPlan2008Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=ufcs_UnrestrictedStockAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=ufcs_DirectorPlan2005Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Stock-Based Compensation (Activity in the Stock Plan) (Details) - shares	1 Months Ended	6 Months Ended	102 Months Ended	150 Months Ended
	May 31, 2014	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2017
Employee Stock Award Plan-2008
Authorized Shares Available for Future Award Grants
Beginning balance (in shares)		1,248,651	1,900,000
Additional shares authorized (in shares)	1,500,000	0	1,500,000
Number of awards granted (in shares)		(254,620)	(2,867,186)
Number of awards forfeited or expired (in shares)		3,228	464,445
Ending balance (in shares)		997,259	997,259	997,259
Employee Stock Award Plan-2008 \| Options Awards
Authorized Shares Available for Future Award Grants
Number of option awards exercised (in shares)		74,466	1,023,534
Employee Stock Award Plan-2008 \| Unrestricted Stock Awards
Authorized Shares Available for Future Award Grants
Number of awards granted (in shares)		(725)	(8,050)
Employee Stock Award Plan-2008 \| Restricted Stock Awards
Authorized Shares Available for Future Award Grants
Number of restricted stock awards vested (in shares)		0	36,970
Director Plan - 2005
Authorized Shares Available for Future Award Grants
Beginning balance (in shares)		74,771		300,000
Number of awards granted (in shares)		(12,958)		(262,190)
Number of awards forfeited or expired (in shares)		0		24,003
Ending balance (in shares)		61,813	61,813	61,813
Director Plan - 2005 \| Options Awards
Authorized Shares Available for Future Award Grants
Number of option awards exercised (in shares)		6,727		59,200
Number of restricted stock awards vested (in shares)		22,716		54,272