Balance Sheet Account Detail (Property and Equipment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 35,584		$ 35,584		$ 36,617
Accumulated depreciation	(21,893)		(21,893)		(20,584)
Property and equipment, net	13,691		13,691		16,033
Depreciation expense	800	$ 900	2,600	$ 2,800
Production equipment, molds, and office furniture
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	11,302		11,302		11,854
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	7,899		7,899		8,235
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	15,594		15,594		15,535
Construction in progress (software and related implementation, production equipment, and leasehold improvements)
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 789		$ 789		$ 993