Gross amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations, excluding the impact of an increase (decrease) in the valuation allowance for a specified deferred tax asset.

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32123-109318

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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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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Valuation Allowance [Line Items]
Change in valuation allowance		$ 11.8
Deferred federal, state and local tax benefit	$ 9.5	13.5
Valuation allowance	360.7		$ 336.1
Formation of Blackstone Joint Venture [Member]
Valuation Allowance [Line Items]
Change in valuation allowance		85.0
Adoption Of Accounting Standards Update 2016-09 [Member]
Valuation Allowance [Line Items]
Change in valuation allowance		48.5
Federal and State [Member]
Valuation Allowance [Line Items]
Change in valuation allowance	$ 24.6	$ 96.8