Reinsurance (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance receivables	$ 17.0	$ 6.1
Catastrophe [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	3.0
Reinsurers reimbursement percentage	100.00%
Reinsurers reimbursement retention maximum limit	32.0
Reinsurers reimbursement retention aggregate limit	64.0
Commercial Property Risk [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	1.0
Commerical property risk retention	6.0
Reinsurers reimbursement retention aggregate limit	30.0
Reinsurers reimbursement retention for each disaster occurrence	5.0
Reinsurers reimbursement retention for any one disaster occurrence	10.0
Professional Liability [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	1.0
Reinsurers reimbursement retention for each disaster occurrence	2.0
Professional Liability [Member] \| Prior to June 1, 2014 [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance retention percentage	60.00%
Concentration of ceded credit risk percentage	40.00%
Personal Property [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance cede risk percentage	80.00%
Personal Property [Member] \| February 1, 2013 Through February 28, 2014 [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Concentration of ceded credit risk percentage	60.00%
Workers Compensation Loss [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	1.0
Reinsurers reimbursement percentage	100.00%
Reinsurers reimbursement retention maximum limit	10.0
Reinsurers reimbursement retention aggregate limit	28.0
Reinsurers reimbursement retention for each disaster occurrence	14.0
Commercial Liability Risk [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	1.0
Reinsurers reimbursement retention maximum limit	5.0
Occupational Accident [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	1.0
Reinsurers reimbursement retention maximum limit	5.0
Reinsurers reimbursement retention for any one disaster occurrence	10.0
Personal Auto [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance cede risk percentage	50.00%
Personal Auto [Member] \| October 1, 2013 Through September 30, 2014 [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Concentration of ceded credit risk percentage	90.00%
Standard Commercial P & C Business Unit [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance cede risk percentage	100.00%
Excess and Umbrella [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance retention percentage	20.00%
Concentration of ceded credit risk percentage	80.00%
E & S Commercial Business Unit [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	1.0
E & S Commercial Business Unit [Member] \| Commercial Umbrella and Excess Liability Risks [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Retention for reinsurance losses	$ 1.0
Proportional reinsurance retention percentage	10.00%
Concentration of ceded credit risk percentage	90.00%
E & S Commercial Business Unit [Member] \| Commercial Umbrella and Excess Liability Risks [Member] \| Excess of Risk Amount [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Concentration of ceded credit risk percentage	100.00%
E & S Commercial Business Unit [Member] \| Commercial Auto [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance retention percentage	20.00%
Concentration of ceded credit risk percentage	80.00%
General Aviation [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Proportional reinsurance cede risk percentage	80.00%

Commerical property risk retention.

No definition available.

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- Definition

The percentage of credit risk related to ceded insurance contracts.

+ References

No definition available.

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- Definition

The proportional reinsurance retention percentage.

+ References

No definition available.

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- Definition

The proportional reinsurance retention percentage.

+ References

No definition available.

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- Definition

The percentage of reinsurers reimbursement.

+ References

No definition available.

+ Details

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- Definition

The aggregate limit for the reinsurers reimbursement retention.

+ References

No definition available.

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- Definition

The amount of reinsurers reimbursement retention for the any one occurrence.

+ References

No definition available.

+ Details

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The amount of reinsurers reimbursement retention for the each occurrence.

+ References

No definition available.

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- Definition

The maximum limit for the reinsurers reimbursement retention.

+ References

No definition available.

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- Definition

The amount of the retention is usually a multiple of the underlying policy limits exposures on business generated by business units.

+ References

No definition available.

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- Definition

Amount after valuation allowance currently billed or billable under reinsurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 6

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

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-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 7

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 605

-Section 50

-Paragraph 1

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

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