v3.8.0.1

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Fair Value Hierarchy for Financial Assets

The following table represents our fair value hierarchy for our financial assets (cash equivalents and marketable securities) measured at fair value on a recurring basis as of December 31, 2017 (in millions):

	Fair Value Measurements Using
	Level 1				Level 2				Level 3				Total
Cash equivalents	$	306.6			$	38.0			$	—			$	344.6
Marketable securities, available for sale
U.S. government agencies	—				87.3				—				87.3
Commercial paper	—				14.7				—				14.7
Corporate debt	—				5.1				—				5.1
Total marketable securities, available for sale	$	—			$	107.1			$	—			$	107.1

The following table represents our fair value hierarchy for our financial assets (cash equivalents and marketable securities) measured at fair value on a recurring basis as of December 31, 2016 (in millions):

	Fair Value Measurements Using
	Level 1				Level 2				Level 3				Total
Cash equivalents	$	—			$	32.3			$	—			$	32.3
Marketable securities, available for sale
U.S. government agencies	—				22.2				—				22.2
Corporate debt	—				3.8				—				3.8
Commercial paper	—				3.2				—				3.2
Total marketable securities, available for sale	$	—			$	29.2			$	—			$	29.2

X

- Definition

Tabular disclosure of assets, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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X

- References

No definition available.

+ Details

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