Business Combinations - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended		9 Months Ended
	Jan. 03, 2017	Nov. 21, 2016	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2017
Grohmann Engineering GmbH [Member]
Business Acquisition [Line Items]
Acquisition date					Jan. 03, 2017
Cash payment for acquisition	$ 109,500
Business acquisition incentive compensation to employees payable	25,800
Business combination, incentive compensation arrangement employee service period					36 months
Business acquisition, compensation expense				$ 25,800
Total purchase price	$ 109,481
SolarCity [Member]
Business Acquisition [Line Items]
Acquisition date					Nov. 21, 2016
Total purchase price		$ 2,100,000
Adjustment to the acquisition date fair value			$ 18,200	$ 11,600