Aggregate purchase price of convertible preferred stock.

No definition available.

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Namespace Prefix:	box_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale of Stock Closing Date.

+ References

No definition available.

+ Details

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Namespace Prefix:	box_
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Balance Type:	na
Period Type:	duration

- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramExpirationDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
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- Details

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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=box_KKRCreditAdvisorsUSLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Subsequent Events - Additional Information (Details) - USD ($)	Jun. 02, 2021	May 12, 2021	Apr. 07, 2021
Subsequent Event \| Tender Offer
Subsequent Event [Line Items]
Expiration date	Jun. 29, 2021
Class A Common Stock \| Subsequent Event \| Tender Offer
Subsequent Event [Line Items]
Authorized purchase amount	$ 500,000,000
Class A Common Stock \| Subsequent Event \| Tender Offer \| Minimum
Subsequent Event [Line Items]
Purchase price per share	$ 22.75
Class A Common Stock \| Subsequent Event \| Tender Offer \| Maximum
Subsequent Event [Line Items]
Purchase price per share	$ 25.75
KKR \| Series A Convertible Preferred Stock
Subsequent Event [Line Items]
Issuance and sale, number of shares			500,000
Shares issued, par value			$ 0.0001
Aggregate purchase price			$ 500,000,000
Sale price per share			$ 1,000
KKR \| Series A Convertible Preferred Stock \| Subsequent Event
Subsequent Event [Line Items]
Sale of stock closing date		May 12, 2021