Stockholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands							1 Months Ended		9 Months Ended
	Jun. 10, 2021	Jul. 25, 2017	Aug. 28, 2015	Jul. 24, 2015	Dec. 28, 2012	Feb. 09, 2007	May 31, 2020	Jun. 30, 2018	Sep. 30, 2021	Sep. 30, 2020	Jun. 09, 2021	Jun. 08, 2021	Feb. 03, 2021	Oct. 31, 2020	Oct. 01, 2020	Dec. 31, 2019	Apr. 30, 2018	Mar. 31, 2018	Aug. 31, 2017
Capital Unit [Line Items]
Payments for repurchase of equity	$ 900								$ 900	$ 0
Authorized (in shares)	4,908,393
Price per share of stock sold (in dollars per share)											$ 10.00
Total proceeds	$ 150,000
Class A
Capital Unit [Line Items]
Number of shares issued in transaction (in shares)						911,500
Authorized (in shares)	3,136,518
Capital shares reserved for future issuance (in shares)									185,000
Class C
Capital Unit [Line Items]
Number of shares issued in transaction (in shares)					300,000
Authorized (in shares)	400,000
Price per share of stock sold (in dollars per share)					$ 10
Total proceeds					$ 3,000
Capital shares reserved for future issuance (in shares)									100,000
Class B
Capital Unit [Line Items]
Authorized (in shares)	513,846
Class D
Capital Unit [Line Items]
Number of shares issued in transaction (in shares)				221,739
Authorized (in shares)	236,521
Price per share of stock sold (in dollars per share)				$ 33.82
Total proceeds				$ 7,215
Stock issuance costs paid				$ 285
Class E
Capital Unit [Line Items]
Number of shares issued in transaction (in shares)		112,916
Authorized (in shares)	112,916
Price per share of stock sold (in dollars per share)		$ 35.42
Total proceeds		$ 3,963
Stock issuance costs paid		$ 37
Class G
Capital Unit [Line Items]
Authorized (in shares)	11,482
Class F
Capital Unit [Line Items]
Number of shares issued in transaction (in shares)								492,110
Authorized (in shares)	492,110
Price per share of stock sold (in dollars per share)								$ 54.87
Total proceeds								$ 26,790
Stock issuance costs paid								$ 210
Class H
Capital Unit [Line Items]
Authorized (in shares)	5,000
City Semi | Class H
Capital Unit [Line Items]
Equity interest issued or issuable (in shares)							4,500
Members' Equity | Class B
Capital Unit [Line Items]
Authorized (in shares)	513,846															243,000
Private Warrants
Capital Unit [Line Items]
Warrants issued (in shares)									10,150,000
Exercise price (in dollars per share)									$ 11.50
Common warrant | Trinity term loan, due 2022 | Class G
Capital Unit [Line Items]
Warrants issued (in shares)																		6,250
Exercise price (in dollars per share)																		$ 35.42
Common warrant | Trinity term loan, due 2022 | Class G | Loans
Capital Unit [Line Items]
Warrants issued (in shares)								6,250,000						1,844,000	1,844
Exercise price (in dollars per share)								$ 35.42							$ 35.42		$ 35.42
Common warrant | PacWest Term Loan and Revolving Line of Credit | Line of credit
Capital Unit [Line Items]
Warrants issued (in shares)																	3,388		3,388,000
Investor | Class D
Capital Unit [Line Items]
Number of shares issued in transaction (in shares)			14,782
Price per share of stock sold (in dollars per share)			$ 33.82
Total proceeds			$ 500
PacWest | Private Warrants | Class G
Capital Unit [Line Items]
Warrants issued (in shares)												3,388
Warrants demanded (in shares)													52,632