Related Parties (Details) - FS&C [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Related Party Transaction Amount of Assets in Defined Contributions Plans			$ 22.8
Related Party Transaction Percent of Assets in Defined Contribution Plan Assets			6.00%
Trinity [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Assets Managed by Investment Advisory Firm under Director's Management		$ 85.8	$ 154.7
Related Party Transaction, Expenses from Transactions with Related Party	$ 0.1	0.3	0.4
Pension Plans, Defined Benefit [Member] \| Investment Management Services for Defined Benefit Plan [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	0.4	0.4	0.3
Assets under Management, Carrying Amount	$ 137.2	$ 159.2	$ 148.6

Amounts Invested in Defined Contribution Plan Mutual Fund Managed by a Director's Investment Advisory Firm

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- Definition

Amounts Invested in Defined Contribution Plan Mutual Fund Managed by a Director's Investment Advisory Frim, Percentage of Total Defined Contribution Plan Investments

+ References

No definition available.

+ Details

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- Definition

Investment Assets Managed by a Directors Investment Advisory Firm

+ References

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- Definition

The carrying amount of assets an investment adviser manages on behalf of investors.

+ References

No definition available.

+ Details

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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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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