Derivative Instruments	12 Months Ended
Derivative Instruments	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	m time to time, we may enter into derivative financial instrument transactions to manage or reduce our market risk. We manage our debt portfolio to achieve an overall desired position of fixed and floating rates. We enter into foreign currency forward contracts and cross-currency swap contracts to economically hedge our exposure to fluctuations in various foreign currencies. The major risks from interest rate derivatives include changes in the interest rates affecting the fair value of such instruments, potential increases in interest expense due to market increases in floating interest rates, changes in foreign exchange rates and the creditworthiness of the counterparties in such transactions. We monitor the creditworthiness of our counterparties, which are multinational commercial banks. The fair values of all our outstanding derivative instruments are determined using a model with Level 2 inputs including quoted market prices for contracts with similar terms and maturity dates. Warrants – Predecessor During the fourth quarter of 2016, in conjunction with the issuance of 84.5 million ordinary shares, we issued one warrant (“Old Warrant”) that gave the holder the option to acquire an additional 84.5 million ordinary shares. The exercise price on the Old Warrant was $6.43 per share and was exercisable prior to May 21, 2019. The option period lapsed and the warrants expired unexercised with a fair value of zero. The Old Warrant was carried at fair value on the Consolidated Balance Sheets and changes in the fair value were reported through earnings. The Old Warrant fair value was a Level 2 valuation and was estimated using the Black Scholes valuation model. Inputs to the model included Weatherford’s share price, volatility of our share price, and the risk-free interest rate. We recognized an insignificant gain in May 2019 related to the Old Warrant expiration. In 2018, we recognized a gain of $70 million with changes in fair value of the Old Warrant recorded each period in “Other Expense, Net” on the accompanying Consolidated Statements of Operations. The change in fair value of the Old Warrant during 2018 was primarily driven by eliminating the warrant share value associated with any future equity issuance and a decrease in Weatherford’s stock price. Derivatives We enter into contracts to hedge our exposure to currency fluctuations in various foreign currencies. At December 31, 2020 and December 31, 2019, we had outstanding foreign currency forward contracts with notional amounts aggregating to $337 million and $389 million, respectively. These foreign currency forward contracts are not designated as hedges under ASU 2014-03, Derivatives and Hedging (Topic 815). The notional amounts of our foreign currency forward contracts do not generally represent amounts exchanged by the parties and thus are not a measure of the cash requirements related to these contracts or of any possible loss exposure. The amounts actually exchanged at maturity are calculated by reference to the notional amounts and by other terms of the derivative contracts, such as exchange rates. Our foreign currency derivatives are not designated as hedges under ASC 815, and the changes in fair value of the contracts were not material to our consolidated results and are recorded in each period in “Other Expense, Net” on the accompanying Consolidated Statements of Operations.