Investments - Available-For-Sale Securities Narrative (Details) $ in Millions	Dec. 31, 2016 USD ($) Affiliate
Schedule of Available-for-sale Securities [Line Items]
Number of investment affiliates exceeding shareholder's equity ten percent threshold limit \| Affiliate	0
Threshold limit of investments based on shareholders' equity (percent)	10.00%
Securities on deposit with state insurance departments	$ 45.9
Business owned life insurance cost	33.0
Fixed maturities
Schedule of Available-for-sale Securities [Line Items]
FAL deposit assets	95.6
Short-term investments
Schedule of Available-for-sale Securities [Line Items]
FAL deposit assets	1.5
Revolving credit agreement
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities pledged as collateral	$ 252.3

Business Owned Life Insurance Cost.

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Number of Investment Affiliates Exceeding Shareholder's Equity Ten Percent Threshold Limit

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Threshold limit of investments based on shareholders equity.

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- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 320
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=28366721&loc=d3e22002-158495

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The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5086-111524

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The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

+ 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 210.5-02.8,17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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