Reinsurance (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Historical Average Claims Ratios, Period, Minimum	5 years
Historical Average Claims Ratios, Period, Maximum	10 years
Hollenfels [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Share of incurred and paid claims	$ 3.6
Share of claims incurred but not reported	$ 8.3

Historical Average Claims Ratios, Period, Maximum

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- Definition

Historical Average Claims Ratios, Period, Minimum

+ References

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- Definition

Revenue from insurance services, including net premiums earned, gain on sale of insurance block, agency management fees and insurance contract fees and commissions.

+ References

+ Details

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- Definition

Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.5)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: 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

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- 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.

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