Fair Value (Details 3) (Fair value measurements on a recurring basis, USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Indemnity \| Real estate
Fair value inputs assets quantitative information
Fair value (in dollars)	$ 7.0	$ 8.0
Indemnity \| Available-for-sale securities
Fair value inputs assets quantitative information
Fair value (in dollars)	0.1
Exchange \| Corporate debt securities \| Market approach
Fair value inputs assets quantitative information
Fair value (in dollars)	7.0	7.0
Unobservable input
Comparable transaction EBITDA multiples (as a multiple)	8.0	8.0
Comparable security yield (as a percent)	6.00%	6.00%
Exchange \| Corporate debt securities \| Market approach \| Weighted average
Unobservable input
Comparable transaction EBITDA multiples (as a multiple)	8.0	8.0
Comparable security yield (as a percent)	6.00%	6.00%
Exchange \| Nonredeemable preferred stock \| Market approach
Fair value inputs assets quantitative information
Fair value (in dollars)	1.0	1.0
Exchange \| Common stock \| Market approach
Fair value inputs assets quantitative information
Fair value (in dollars)	15.0	15.0
Unobservable input
Comparable transaction EBITDA multiples (as a multiple)	8.0	8.0
Discount for lack of marketability (as a percent)	10.00%	10.00%
Exchange \| Common stock \| Market approach \| Weighted average
Unobservable input
Comparable transaction EBITDA multiples (as a multiple)	8.0	8.0
Discount for lack of marketability (as a percent)	10.00%	10.00%
Exchange \| Real estate
Fair value inputs assets quantitative information
Fair value (in dollars)	51.0	71.0
Exchange \| Available-for-sale securities
Fair value inputs assets quantitative information
Fair value (in dollars)	$ 82.0	$ 92.0

The observable yield of another security with similar characteristics to the security being valued, used as an input to measure fair value.

No definition available.

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- Definition

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Market valuation of entity divided by earnings before interest, taxes, depreciation, and amortization (EBITDA), used as an input to measure fair value.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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