Condensed Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net loss	$ (22,130)	$ (6,376)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	425	153
Provision for doubtful accounts	331	4
Provision for warranties	74	286
Provision for inventory	391	55
Change in fair value of warrants	6	288
Non-cash interest expense	12	288
Stock-based compensation expense	1,664	1,082
Loss on disposal of property and equipment	122
Changes in assets and liabilities:
Accounts receivable	1,514	(1,742)
Prepaid expenses, other current assets and other assets	(574)	(657)
Inventories	1,406	305
Accounts payable	(635)	(520)
Accrued and other liabilities	428	670
Customer deposits	(2,530)	(416)
Net cash used in operating activities	(19,496)	(6,580)
Cash flows from investing activities:
Purchase of property and equipment	(874)	(511)
Business acquisition	(6,759)
Net cash used in investing activities	(7,633)	(511)
Cash flows from financing activities:
Proceeds from exercise of stock options	57	92
Proceeds from issuance of common stock under ESPP	430
Deferred equity issuance costs, IPO		(71)
Net cash provided by financing activities	487	21
Net decrease in cash and cash equivalents	(26,642)	(7,070)
Cash and cash equivalents at:
Beginning of period	112,801	96,729
End of period	86,159	89,659
Supplemental disclosure of cash flow information:
Interest paid		1,051
Supplemental disclosure of non-cash investing and financing activities:
Property and equipment in accounts payable		$ 85
Acquisition of business, deferred and contingent consideration obligations at fair value	$ 550