Stock-Based Compensation - Incentive Awards (Details) shares in Millions	12 Months Ended
Dec. 31, 2021 shares
Kyndryl Holdings, Inc
Stock-Based Compensation
Stock adjustment ratio	1.03
Adjusted stock options issued	0.8
Long-term performance plans
Stock-Based Compensation
Shares authorized under existing stock based compensation plans (in shares)	293.0
Additional shares considered authorized under previous stock based compensation plans (in shares)	66.0
Unused shares available to be granted (in shares)	96.0

Number of adjusted stock options issued under share based compensation arrangement.

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- Definition

Stock adjustment ratio for issuance of award under share based arrangement.

+ References

No definition available.

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- 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.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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