Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

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

- Definition

Amount debtor-in-possession financing arranged (but not necessarily all borrowed).

+ References

No definition available.

+ Details

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

- Definition

Amount of debtor-in-possession borrowings outstanding.

+ References

No definition available.

+ Details

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

- Definition

Percentage of fee on unused borrowings under debtor-in-possession financing arrangement.

+ References

No definition available.

+ Details

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

- Definition

Amount of letters of credit outstanding under debtor-in-possession financing arrangement.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ 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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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

- Definition

Debt instrument, Covenant, Minimum Liquidity, Amount

+ References

No definition available.

+ Details

Name:	wft_DebtinstrumentCovenantMinimumLiquidityAmount
Namespace Prefix:	wft_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debtor-in-Possession Financing, Proceeds From Borrowings

+ References

No definition available.

+ Details

Name:	wft_DebtorinPossessionFinancingProceedsFromBorrowings
Namespace Prefix:	wft_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Prepetition Charges

+ References

No definition available.

+ Details

Name:	wft_PrepetitionCharges
Namespace Prefix:	wft_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=wft_DIPCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=wft_DebtorinPossessionRevolvingCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=wft_TermLoanAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
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Chapter 11 Proceedings and Ability to continue as a Going Concern - Debtor in Possession Credit Agreement (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jul. 03, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Financing fee on unused borrowings		0.375%		0.375%
Outstanding borrowings		$ 1,386		$ 1,386		$ 0
Prepetition Charges		0	$ 0	86	$ 0
DIP Credit Agreement
Debt Instrument [Line Items]
Minimum liquidity amount	$ 150
Proceeds from borrowings	1,400
Repayments of long-term debt	616
Outstanding letters of credit	271	$ 371		$ 371
Debtor in Possession Revolving Credit Agreement \| DIP Credit Agreement
Debt Instrument [Line Items]
Amount arranged under DIP Agreement	750
Term Loan Agreement \| DIP Credit Agreement
Debt Instrument [Line Items]
Amount arranged under DIP Agreement	$ 1,000
Maximum \| LIBOR \| DIP Credit Agreement
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	3.00%
Maximum \| Base Rate \| DIP Credit Agreement
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	2.00%
Minimum \| LIBOR \| DIP Credit Agreement
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	0.00%