Investments Available for Sale Securities (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2015	Dec. 31, 2016	Jun. 27, 2015
Schedule of Available-for-sale Securities [Line Items]
Equity method investment, other than temporary impairment		$ 22.3
Transfer from investments		15.5
Other than temporary impairment losses, investments, portion recognized in earnings, net, available-for-sale securities	$ 10.7	1.8
Net unrealized investment gains (losses):
Equity securities, at cost less impairments	6.4	16.5	$ 17.1
Gross unrealized gains	9.3	21.7	5.7
Gross unrealized losses	(0.8)	0.0	(10.1)
Unrealized Gain (Loss) on Investments		8.7
Available-for-sale securities, gross unrealized gain		1.0
Available-for-sale securities [Member]
Net unrealized investment gains (losses):
Estimated fair value of equity securities	$ 14.9	$ 38.2	$ 12.7

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

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Amount of equity securities categorized neither as held-to-maturity nor as trading.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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Value of investments transferred from the entity's investments in noncash transactions.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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