RETIREMENT SAVINGS PLAN - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, cost	$ 3.5	$ 2.1
Percent of match	100.00%
Percent of employees' gross pay	1.00%
Percent of match beyond initial 1%	50.00%
Additional percent of employees' gross pay beyond initial 1%	1.00%
Minimum
Defined Contribution Plan Disclosure [Line Items]
Additional percent of employees' gross pay beyond initial 1%	1.00%
Maximum
Defined Contribution Plan Disclosure [Line Items]
Additional percent of employees' gross pay beyond initial 1%	6.00%

Defined Contribution Plan, Employer Matching Contribution, Additional Percent of Employees' Gross Pay Beyond Initial 1%

No definition available.

Name:	nkla_DefinedContributionPlanEmployerMatchingContributionAdditionalPercentOfEmployeesGrossPayBeyondInitial1
Namespace Prefix:	nkla_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Defined Contribution Plan, Employer Matching Contribution, Percent of Match Beyond Initial 1%

+ References

No definition available.

+ Details

Name:	nkla_DefinedContributionPlanEmployerMatchingContributionPercentOfMatchBeyondInitial1
Namespace Prefix:	nkla_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

Name:	us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: