Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability 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)(1a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability 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=66048111&loc=d3e19207-110258

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- Definition

Call option period of time to acquire remaining shares as part of a business acquisition.

+ References

No definition available.

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- Definition

Percentage of voting equity interests remaining yet to be acquired in the business combination.

+ References

No definition available.

+ Details

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Financial Instruments - Change in Fair value (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Nov. 30, 2015	Apr. 02, 2017	Dec. 31, 2018	Dec. 31, 2018	Nov. 30, 2015
Apex
Reconciliation of changes in fair value of all financial assets and liabilities
Shares remaining to be acquired (as a percent)				10.00%	20.00%
Call option term	3 years
Outstanding shares acquired (as a percent)		10.00%			80.00%
Purchase price	$ 20.4	$ 2.9
Aggregate ownership percentage				90.00%
Redeemable financial instrument
Reconciliation of changes in fair value of all financial assets and liabilities
Balance at the beginning of the period			$ 2.9
Total realized and unrealized (gains) losses included in Comprehensive income			(0.1)
Balance at the ending of the period			2.8
Liability recorded at acquisition date fair value			$ 2.9	$ 2.8
Redeemable financial instrument \| Apex
Reconciliation of changes in fair value of all financial assets and liabilities
Balance at the ending of the period	5.5
Liability recorded at acquisition date fair value	$ 5.5				$ 5.5