Amount of capital contribution to own voting interest in investee entity.

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- Definition

Investor Relations, Quarterly Consulting Fee, Minimum

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No definition available.

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- Definition

[Line Items] for Organization, Consolidation, And Basis of Preparation [Table]

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No definition available.

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- Definition

Purchase and Sell Agreement, Right of First Refusal, Catastrophe Excess of Loss Reinsurance Program Limit

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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-Paragraph 21
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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ORGANIZATION, CONSOLIDATION AND BASIS OF PRESENTATION (Narrative) (Details) - USD ($)		3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 22, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2018	Mar. 31, 2018	Feb. 21, 2018	Dec. 31, 2017
Organization, Consolidation, And Basis of Preparation [Line Items]
Repayments of promissory note				$ 5,000,000	$ 0
Monarch Delaware Holdings LLC [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Capital contribution for voting interests							$ 12,300,000
Ownership percentage							42.40%	42.40%	100.00%
Transatlantic Reinsurance Company [Member] \| Monarch Delaware Holdings LLC [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Capital contribution for voting interests							$ 4,400,000
Ownership percentage							15.20%
Repayments of promissory note				$ 5,000,000
Scenario, Forecast [Member] \| Transatlantic Reinsurance Company [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Quarterly consulting fee, minimum						$ 10,000,000
Scenario, Forecast [Member] \| Crosswinds [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Quarterly consulting fee, minimum						75,000
Purchase and sell agreement, right of first refusal, catastrophe excess of loss reinsurance program limit						$ 10,000,000.0
Homeowners Multiperil Insurance Product Line [Member] \| Customer Concentration Risk [Member] \| Ivantage Select Agency Inc [Member] \| Premiums Written Net [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Concentration risk, percentage		24.40%	24.20%	23.70%	23.60%
Homeowners Multiperil Insurance Product Line [Member] \| Customer Concentration Risk [Member] \| SageSure Insurance Managers LLC [Member] \| Premiums Written Net [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Concentration risk, percentage		14.50%	9.80%	13.30%	9.20%
Monarch National Insurance Company [Member] \| TransRe [Member]
Organization, Consolidation, And Basis of Preparation [Line Items]
Repayments of promissory note	$ 5,000,000