Property and Equipment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	$ 4,948	$ 5,397
Less accumulated depreciation	(2,057)	(1,692)
Property and Equipment, Net	2,891	3,705
Office furniture and equipment
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	2,073	1,631
Office furniture and equipment | Minimum
Property Plant And Equipment [Line Items]
Property and Equipment, Useful Life	3 years
Office furniture and equipment | Maximum
Property Plant And Equipment [Line Items]
Property and Equipment, Useful Life	7 years
Rental inventory
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	2,142	3,147
Property and Equipment, Useful Life	5 years
Vehicles
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	76	76
Property and Equipment, Useful Life	5 years
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	486	375
Leasehold improvements | Minimum
Property Plant And Equipment [Line Items]
Property and Equipment, Useful Life	2 years
Leasehold improvements | Maximum
Property Plant And Equipment [Line Items]
Property and Equipment, Useful Life	6 years
Assembly equipment
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	$ 171	$ 168
Property and Equipment, Useful Life	7 years