Reinsurance coverage, maximum provisional limit, amount

No definition available.

Name:	uihc_AggregateCoverageForCoveredLossesUnderReinsuranceContract
Namespace Prefix:	uihc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

According to the ISO, a catastrophe loss is defined as a single unpredictable incident or series of closely related incidents that result in at least this amount in U.S industry-wide direct insured losses to property.

+ References

No definition available.

+ Details

Name:	uihc_ISOCatastropheDefinition
Namespace Prefix:	uihc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Insurance Commissions and Fees, Flood Program

+ References

No definition available.

+ Details

Name:	uihc_InsuranceCommissionsAndFeesFloodProgram
Namespace Prefix:	uihc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of Flood Premiums Ceded

+ References

No definition available.

+ Details

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Namespace Prefix:	uihc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Reinsurance Retention Policy, Coverage Percentage Hurricane Event

+ References

No definition available.

+ Details

Name:	uihc_ReinsuranceRetentionPolicyCoveragePercentageHurricaneEvent
Namespace Prefix:	uihc_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Reinsurance Retention Policy, Number Of Private Reinsurers

+ References

No definition available.

+ Details

Name:	uihc_ReinsuranceRetentionPolicyNumberOfPrivateReinsurers
Namespace Prefix:	uihc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Reinsurance Retention Policy, Participation Rate

+ References

No definition available.

+ Details

Name:	uihc_ReinsuranceRetentionPolicyParticipationRate
Namespace Prefix:	uihc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The unexpired portion of premiums ceded on policies in force as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 340
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6485982&loc=d3e22818-158507

+ Details

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

- Definition

Amount of recovery (expense) related to provision for policy benefits and costs incurred for policies assumed and ceded.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6811-158387

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Stated amount that is the upper retention limit per entity policy.

+ References

No definition available.

+ Details

Name:	us-gaap_ReinsuranceRetentionPolicyAmountRetained
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of risk reinsured in excess of stated retention per company policy.

+ References

No definition available.

+ Details

Name:	us-gaap_ReinsuranceRetentionPolicyExcessRetentionAmountReinsured
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	uihc_ReinsuranceEventTypeAxis=uihc_SecondAndSubsequentCatastrophicEventsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	uihc_InsuranceProductLineAxis=us-gaap_CatastropheMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	uihc_ReinsuranceEventTypeAxis=uihc_FirstCatastrophicEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	uihc_ReinsuranceEventTypeAxis=uihc_SecondCatastrophicEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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Namespace Prefix:
Data Type:	na
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- Details

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

- Details

Name:	dei_LegalEntityAxis=uihc_BlueLineMember
Namespace Prefix:
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Reinsurance (Details)			3 Months Ended		9 Months Ended
Reinsurance (Details)	Jun. 01, 2017 USD ($) catastrophic_event reinsurer	Jun. 01, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Reinsurance Retention Policy [Line Items]
Prepaid reinsurance premiums			$ 285,121,000		$ 285,121,000		$ 132,564,000
Cash recoveries under reinsurance agreements			20,419,000	$ 9,747,000	$ 40,984,000	$ 10,604,000
Flood premiums ceded (percentage)					100.00%
Insurance commissions and fees under Flood Program			$ 308,000	$ 270,000	$ 905,000	$ 772,000
Minimum
Reinsurance Retention Policy [Line Items]
ISO Catastrophe Definition	$ 25,000,000
Second And Subsequent Catastrophic Events \| Maximum
Reinsurance Retention Policy [Line Items]
Amount of risk reinsured in excess of stated retention	2,747,500,000
Catastrophe
Reinsurance Retention Policy [Line Items]
Prepaid reinsurance premiums	$ 314,169,000
Catastrophe \| First Catastrophic Event
Reinsurance Retention Policy [Line Items]
Reinsurance Retention Policy, Coverage Percentage Hurricane Event \| catastrophic_event	0.010
Catastrophe \| First Catastrophic Event \| Maximum
Reinsurance Retention Policy [Line Items]
Stated amount of upper retention limit per policy	$ 55,000,000
Catastrophe \| Second Catastrophic Event
Reinsurance Retention Policy [Line Items]
Reinsurance Retention Policy, Coverage Percentage Hurricane Event \| catastrophic_event	0.020
Catastrophe \| Second And Subsequent Catastrophic Events \| Maximum
Reinsurance Retention Policy [Line Items]
Stated amount of upper retention limit per policy	$ 30,000,000
Catastrophe \| Florida Hurricane Catastrophe Fund \| FLORIDA
Reinsurance Retention Policy [Line Items]
Aggregate Coverage for Covered Losses Under Reinsurance Contract		$ 789,000,000
Reinsurance Retention Policy, Participation Rate		45.00%
Catastrophe \| Unaffiliated Private Reinsurers
Reinsurance Retention Policy [Line Items]
Number of private reinsurers \| reinsurer	43
Catastrophe \| Unaffiliated Private Reinsurers \| Maximum
Reinsurance Retention Policy [Line Items]
Aggregate Coverage for Covered Losses Under Reinsurance Contract	$ 1,928,000,000
BlueLine \| Catastrophe \| Second And Subsequent Catastrophic Events \| Maximum
Reinsurance Retention Policy [Line Items]
Stated amount of upper retention limit per policy	$ 5,000,000