Balance Sheet Account Detail (Property and Equipment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 36,867		$ 36,475
Accumulated depreciation	(18,269)		(17,263)
Property and equipment, net	18,598		19,212
Depreciation expense	1,000	$ 1,400
Production equipment, molds, and office furniture
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	12,137		12,118
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	8,151		8,115
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	15,499		15,499
Construction in progress (software and related implementation, production equipment, and leasehold improvements)
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 1,080		$ 743