Equity Incentive Plans - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended		1 Months Ended	3 Months Ended	9 Months Ended	1 Months Ended	3 Months Ended		9 Months Ended
	Aug. 31, 2012 Tranches	Sep. 30, 2014	Sep. 30, 2013	Jan. 31, 2014 Performance-based Stock Option Grant [Member] Tranches	Sep. 30, 2014 Performance-based Stock Option Grant [Member]	Sep. 30, 2014 Performance-based Stock Option Grant [Member]	Aug. 31, 2012 2012 CEO Grant [Member]	Sep. 30, 2014 2012 CEO Grant [Member]	Sep. 30, 2013 2012 CEO Grant [Member]	Sep. 30, 2014 2012 CEO Grant [Member] Tranches	Sep. 30, 2013 2012 CEO Grant [Member]	Sep. 30, 2014 First Model X Production Vehicle [Member]	Sep. 30, 2014 12-month period [Member] Vehicle	Sep. 30, 2014 First Gen III Production Vehicle [Member]	Sep. 30, 2014 Three year period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted				782,500			5,274,901
Number of vesting tranches				4						6
Portion of stock options scheduled to vest upon successful completion of performance objectives												0.25	0.25	0.25	0.25
Number of vehicle production													100,000
Gross margin															30.00%
Stock-based compensation expense		$ 111,980,000	$ 55,566,000		$ 2,900,000	$ 9,200,000		$ 3,800,000	$ 3,600,000	$ 18,200,000	$ 8,800,000
CEO Grant consists of number of vesting tranches	10
Market capitalization		4,000,000,000
Initial market capitalization								3,200,000,000		3,200,000,000
Cash compensation received by CEO										$ 0