Commitments and Contingencies (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($)
Long-term Purchase Commitment [Line Items]
Aggregate residual value at lease expiration for vehicle leases	$ 13,814
Guaranteed aggregate residual value at lease expiration for vehicle leases	11,143
Liability for the estimated end of term loss related to residual value guarantee	333
Long-term purchase commitment, amount	$ 24,000
Long-term purchase commitment, period	24 months
Green Machine supply commitment
Long-term Purchase Commitment [Line Items]
Purchase obligation, due in next twelve months	$ 12,000
Long-term purchase commitment, amount	$ 24,000
Long-term purchase commitment, period	2 years
Software development arrangement
Long-term Purchase Commitment [Line Items]
Purchase obligation, due in next twelve months	$ 3,000
Long-term purchase commitment, amount	$ 8,000
Long-term purchase commitment, period	4 years