v3.8.0.1

Financial Statement Details (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure of Financial Statement Details [Abstract]

Short Term Marketable Securities, Available for Sale

Short-term marketable securities, consisting solely of debt securities were as follows:

	December 31, 2017
	Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Estimated Market Value
U.S. government agencies	$	87.5			$	—			$	(0.2	)		$	87.3
Commercial paper	14.7				—				—				14.7
Corporate debt	5.1				—				—				5.1
Total	$	107.3			$	—			$	(0.2	)		$	107.1

	December 31, 2016
	Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Estimated Market Value
U.S. government agencies	$	22.2			$	—			$	—			$	22.2
Corporate debt	3.8				—				—				3.8
Commercial paper	3.2				—				—				3.2
Total	$	29.2			$	—			$	—			$	29.2

Accounts Receivable

Accounts Receivable

	December 31,
	2017				2016
Accounts receivable	$	145.8			$	114.3
Less allowance for doubtful accounts, sales returns and discounts	(11.5		)		(12.6		)
Total	$	134.3			$	101.7

Inventory

Inventory

	December 31,
	2017				2016
Raw materials	$	20.0			$	20.1
Work-in-process	8.2				2.3
Finished goods	17.0				23.0
Total	$	45.2			$	45.4

Property and Equipment

Property and Equipment

	December 31,
	2017				2016
Building (1)	$	6.0			$	6.0
Furniture and fixtures	5.7				5.8
Computer equipment	25.6				22.7
Machinery and equipment	33.8				31.4
Leasehold improvements	41.7				25.6
Construction in progress (2)	87.6				65.1
Total	200.4				156.6
Accumulated depreciation	(54.8		)		(47.2		)
Property and equipment, net	$	145.6			$	109.4

Accounts Payable and Accrued Liabilities

Accounts Payable and Accrued Liabilities

	December 31,
	2017				2016
Accounts payable trade(1)	$	46.7			$	41.1
Accrued tax, audit, and legal fees	7.1				4.5
Accrued rebates	13.9				8.2
Accrued warranty	8.8				9.8
Accrued other(1)	10.7				4.5
Total	$	87.2			$	68.1

Accrued Payroll And Related Expenses

Accrued Payroll and Related Expenses

	December 31,
	2017				2016
Accrued paid time off	$	7.9			$	6.4
Accrued wages, bonus and taxes	37.6				24.5
Other accrued employee benefits	3.0				2.5
Total	$	48.5			$	33.4

Accrued Warranty

Accrued Warranty

Warranty costs are reflected in the consolidated statements of operations as cost of sales. A reconciliation of our accrued warranty costs for the twelve months ended December 31, 2017 and 2016 were as follows:

	Years Ended December 31,
	2017				2016
Beginning balance	$	9.8			$	3.3
Charges to costs and expenses	18.4				25.0
Costs incurred	(19.4		)		(18.5		)
Ending balance	$	8.8			$	9.8

Schedule of Other Assets and Other Liabilities [Table Text Block]

Other Liabilities

	December 31, 2017				December 31, 2016
Financing lease obligations	$	6.7			$	6.7
Deferred rent	8.7				7.3
Other	2.8				2.6
Total	$	18.2			$	16.6

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