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Convertible preferred stock conversion ratio.

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Percentage of debt conversion convertible instrument into per share price.

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Number of shares of equity interests issued or issuable to acquire entity.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Face amount or stated value per share of common stock.

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Face (par) amount of debt instrument at time of issuance.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of shares issued as [noncash or part noncash] consideration for a business or asset acquired. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The cash inflow from the additional capital contribution to the entity.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Business Combination and Recapitalization - Additional Information (Detail)		1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Oct. 29, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($)	Jun. 30, 2021 USD ($) $ / shares shares	Dec. 31, 2018	May 19, 2021 $ / shares	Dec. 31, 2020 USD ($) $ / shares	May 31, 2020 USD ($)
Common stock par or Stated value per share				$ 0.00001
Aggregate Consideration for the Business Combination \| $	$ 1,800,000,000
No of Shares issued under Business Combination \| shares	179,192,713
Common stock par value				$ 0.00001
Convertible Preferred Stock Conversion Ratio				2.7162
HF Holdco LLC [Member] \| Demand Note [Member]
Advance in the form of notes \| $				$ 250,000,000
Bridge Notes [Member]
Convertible Preferred Stock Conversion Ratio				2.7162
Noncash or Part Noncash Acquisition, Debt Assumed \| $		$ 10,000,000.0
Bridge Notes [Member] \| HF Holdco LLC [Member]
Issuance of notes \| $							$ 0	$ 250,000,000
Interest Expense [Member] \| Bridge Notes [Member]
Accretion of debt discount \| $			$ 200,000
Common Stock [Member]
Common stock par or Stated value per share				$ 11.50		$ 0.00001
Common stock par value				11.50		$ 0.00001
Common Stock [Member] \| Spartan Energy Acquisition Corp [Member]
Business combination share price	$ 10.00
PIPE Investor [Member] \| Spartan Energy Acquisition Corp [Member]
Common stock par or Stated value per share	$ 10.00
Proceeds from issuance of common stock \| $	$ 500,000,000.0
Common stock par value	$ 10.00
PIPE Investor [Member] \| Common Stock [Member] \| Spartan Energy Acquisition Corp [Member]
Stock issued during period shares new Shares \| shares	50,000,000
Legacy Fisker Class A common stock [Member]
Common stock par or Stated value per share				0.00001			$ 0.00001
Common stock par value				0.00001			0.00001
Legacy Fisker Class A common stock [Member] \| Bridge Notes [Member]
Noncash or Part Noncash Acquisition, Shares Issued \| shares		1,361,268
Legacy Fisker Class A common stock [Member] \| Bridge Notes [Member] \| Special Purpose Acquisition Corporation Transaction [Member]
Percentage Of Debt Conversion Convertible Instrument Into Per Share price		75.00%
Legacy Fisker Class A common stock [Member] \| Spartan Energy Acquisition Corp [Member]
No of Shares issued under Business Combination \| shares	46,838,585
Class B Common Stock
Common stock par or Stated value per share				0.00001			0.00001
Common stock par value				0.00001			$ 0.00001
Adjustments To Preferred Stock Convertible Conversion Price				$ 0.10
Class B Common Stock \| Spartan Energy Acquisition Corp [Member]
No of Shares issued under Business Combination \| shares	132,354,128
Series A Convertible Preferred stock [Member]
Convertible Preferred Stock Conversion Ratio				2.7162	2.7162
Temporary Equity, Shares Outstanding \| shares				16,983,241
Series B Convertible Preferred stock [Member]
Temporary Equity, Shares Outstanding \| shares				3,765,685
Founder Convertible Preferred Stock [Member]
Temporary Equity, Shares Outstanding \| shares				27,162,191