Restatement of Previously Issued Consolidated Financial Statements - Restatement Background (Details) - USD ($) $ in Thousands	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Operating Lease, Right-of-Use Asset	$ 117,016	$ 90,184	$ 71,789	$ 64,812	$ 63,266	$ 47,016	$ 39,679	$ 33,599	$ 71,789	$ 39,679	$ 90,184	$ 47,016	$ 117,016	$ 63,266
Operating Lease, Liability	113,938												113,938
Loss (benefit) on service contracts				(128)				(142)	277	(873)	25,110	(1,366)	33,125	(1,643)	$ 5,345
Provision for Loss Contracts on Services								162
Net Income (Loss) Available to Common Stockholders, Basic, Restatement	(484,105)	(65,217)	(9,414)	(37,445)	(19,277)	(18,366)	(17,351)	(30,560)	(46,859)	(47,911)	(112,076)	(66,277)	(596,181)	(85,555)	(85,660)
Increase in accumulated deficit	$ (1,946,488)	(1,462,377)	(1,397,160)	(1,387,752)	(1,350,307)	(1,332,259)	(1,314,425)	(1,297,072)	(1,397,160)	(1,314,425)	(1,462,377)	(1,332,259)	$ (1,946,488)	(1,350,307)
Revision of Lease Liability
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Operating Lease, Right-of-Use Asset					112,700									112,700
Operating Lease, Liability					112,700									112,700
Revision of Loss of Accrual Provision
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Loss accrual relating to service contracts		21,000
Loss (benefit) on service contracts														1,600	5,300
Revision of lease right of use assets
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Operating Lease, Right-of-Use Asset		(145,600)									(145,600)
Services performed on fuel cell systems and related infrastructure
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Provision for Loss Contracts on Services								303
Restatement Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Operating Lease, Right-of-Use Asset		90,184	71,789	64,812	63,266	47,016	39,679	33,599	71,789	39,679	90,184	47,016		63,266
Loss (benefit) on service contracts				(128)				(142)	277	(873)	20,804	(1,366)		(1,643)	5,345
Net Income (Loss) Available to Common Stockholders, Basic, Restatement		(25,838)	(745)	47	(989)	(209)	756	444	(705)	1,161	(26,543)	952		(38)	(7,493)
Increase in accumulated deficit		(31,037)	(5,199)	(4,453)	(4,500)	(4,741)	(5,062)	(5,817)	(5,199)	(5,062)	(31,037)	(4,741)		(4,500)
Restatement Adjustments | Revision of Lease Liability
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in accumulated deficit					4,500									4,500	6,200		$ 3,400
Restatement Adjustments | Revision of Loss of Accrual Provision
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Provision for Loss Contracts on Services		$ 20,800	706	95	13	(206)	(363)		801	(201)	$ 21,600	(407)		394	$ 5,300
Restatement Adjustments | Revision of lease right of use assets
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Operating Lease, Right-of-Use Asset			$ (132,900)	$ (118,600)	$ (112,700)	$ (86,700)	$ (60,600)	$ (36,100)	$ (132,900)	$ (60,600)		$ (86,700)		(112,700)
Restatement Adjustments | Revision of Deemed Dividend | Series E Redeemable Convertible Preferred Stock
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deemed Dividend														1,800
Net Income (Loss) Available to Common Stockholders, Basic, Restatement														$ 1,800
Restatement Adjustments | Cumulative effect from adoption of ASC 842
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in accumulated deficit																$ 3,400