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Investment Securities (Significant Unobservable Inputs) (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2016 USD ($) Investment	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) input Investment
Quantitative information for Level 3 Fair Value Measurements Assets
Equity in earnings of unconsolidated affiliates, net of tax	$ 0.0	$ 7.3
Number of Investments with Significant Unobseravble Inputs | Investment	1		1
NR | Preferred Stock | Par Value [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure			$ 70.0
NR | Preferred Stock | Issuer's intent to call [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Fair Value Measurements, Valuation Techniques			70.0
NR | Convertible Preferred Stock [Member] | Multiple of EBITA [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Unobservable Inputs | input			0
Fair Value Measurements, Valuation Techniques			6.0
NR | Convertible Preferred Stock [Member] | Recent transaction [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure			$ 5.7
NR | Seller Priority Surplus Note [Member] | Discounted cash flows
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 38.2		$ 38.0
Timing of interest payments	5 years		5 years
Timing of principal payments	10 years		10 years
Fair Value Measurements, Valuation Techniques	0.125		0.13
NR | Pari Passu Surplus Note [Member] | Discounted cash flows
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 13.6		$ 13.5
Timing of interest payments	5 years		5 years
Timing of principal payments	15 years		15 years
Fair Value Measurements, Valuation Techniques	.225		0.224
MSA [Member] | NR | Preferred Stock | Discounted cash flows
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 70.5
Fair Value Measurements, Valuation Techniques	.0807
PassportCard [Member] | NR | Private equity funds | Recent transaction [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 21.0		$ 21.0
PassportCard [Member] | NR | Private equity funds | Average Share Price [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Fair Value Measurements, Valuation Techniques	1		1.00
Compare.com [Member] | NR | Private equity funds | Recent transaction [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 33.8
Compare.com [Member] | NR | Private equity funds | Average Share Price [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Fair Value Measurements, Valuation Techniques	1.03
Compare.com [Member] | NR | Private equity funds | Recent Transaction Two [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure			$ 33.8
Fair Value Measurements, Valuation Techniques			1.03
OneTitle [Member] | NR | Private equity funds | Recent transaction [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 3.2
OneTitle [Member] | NR | Private equity funds | Average Share Price [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Fair Value Measurements, Valuation Techniques	2.521
Galvanic [Member] | NR | Convertible Preferred Stock [Member] | Multiple of EBITA [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Fair Value Measurements, Valuation Techniques	6
Galvanic [Member] | NR | Convertible Preferred Stock [Member] | Recent transaction [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 5.9
Captricity [Member] | NR | Convertible Preferred Stock [Member] | Recent transaction [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 27.0		$ 27.0
Fair Value Measurements, Valuation Techniques	3.83		3.83
durchblicker.at [Member] | NR | Private equity funds
Quantitative information for Level 3 Fair Value Measurements Assets
Time Until Expiration of Security	4 years		4 years
Volatility Rate	60.00%		60.00%
Risk Free Rate	1.15%		1.15%
durchblicker.at [Member] | NR | Private equity funds | Option pricing method [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Assets, Fair Value Disclosure	$ 10.0		$ 9.6
Standard & Poor's, B Rating [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Basis points	2.50%		2.50%
Standard & Poor's, CCC Rating [Member]
Quantitative information for Level 3 Fair Value Measurements Assets
Basis points	2.50%		2.50%

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 230
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