Gain (Loss) On Issuance Of Treasury Shares, Recognised as a Reduction in Additional Paid in Capital

No definition available.

Name:	borr_GainLossOnIssuanceOfTreasurySharesRecognisedAsAReductionInAdditionalPaidInCapital
Namespace Prefix:	borr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Net Proceeds From Issuance Of Common Stock

+ References

No definition available.

+ Details

Name:	borr_NetProceedsFromIssuanceOfCommonStock
Namespace Prefix:	borr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Of Stock, Maximum Amount Authorized For Issuance

+ References

No definition available.

+ Details

Name:	borr_SaleOfStockMaximumAmountAuthorizedForIssuance
Namespace Prefix:	borr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentsOfStockIssuanceCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

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

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssuedPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of new stock issued during the period.

+ 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(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 4: 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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement.

+ References

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesTreasuryStockReissued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 3: 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(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: 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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodValueNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Value of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 4: 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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 5: 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(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	dei_EntityListingsExchangeAxis=exch_XNYS
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_EntityListingsExchangeAxis=exch_XOSL
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=borr_AtTheMarketOfferingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Equity (Details) - Shares Issued - USD ($) $ / shares in Units, $ in Millions								1 Months Ended		12 Months Ended
	Oct. 14, 2022	Aug. 26, 2022	Aug. 17, 2022	Jan. 31, 2022	Jul. 14, 2021	Mar. 18, 2021	Jan. 22, 2021	Aug. 31, 2022	Jan. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jul. 31, 2021
Equity, Class of Treasury Stock [Line Items]
Issue of common shares (in shares)								76,363,071	13,333,333	92,046,404
Price per share (in dollars per share)	$ 3.6			$ 2.25	$ 1.7	$ 2.4		$ 3.60	$ 2.25
Gross proceeds								$ 260.4	$ 28.9	$ 313.8	$ 46.0	$ 62.8
Gross proceeds										$ 298.1	$ 44.8	$ 60.2
Number of treasury shares reissued (in shares)	90,822				48,393	275,132				90,822	323,525
Value of treasury shares reissued	$ 0.3				$ 0.1	$ 0.7				$ 0.3	$ 0.8
Loss on issuance of treasury shares	$ 3.6				$ 2.0	$ 9.7					$ 11.7
NYSE
Equity, Class of Treasury Stock [Line Items]
Issue of common shares (in shares)		34,696,404	41,666,667							2,350,000
Price per share (in dollars per share)		$ 3.60	$ 3.60							$ 3.78
Gross proceeds		$ 124.9	$ 150.0							$ 8.9
Oslo
Equity, Class of Treasury Stock [Line Items]
Issue of common shares (in shares)				13,333,333			27,058,823
Price per share (in dollars per share)				$ 2.25			$ 1.70		$ 2.25
Gross proceeds				$ 30.0			$ 46.0
At-the-market offering
Equity, Class of Treasury Stock [Line Items]
Amount authorized for issuance													$ 40.0
At-the-market offering \| NYSE
Equity, Class of Treasury Stock [Line Items]
Issue of common shares (in shares)										2,350,000
Price per share (in dollars per share)										$ 3.78
Amount authorized for issuance													$ 40.0
Gross proceeds										$ 8.9
Net proceeds										8.8
Stock issuance costs										$ 0.1