Employee Benefit Plans	12 Months Ended
Dec. 31, 2021
Postemployment Benefits [Abstract]
Employee Benefit Plans	17. Employee Benefit Plans Defined Contribution Plans We maintain defined contribution retirement plans for our U.S., U.K., and third-country national (or TCN) employees. The plan for our U.S. employees (or the 401k Plan), is designed to qualify under Section 401(k) of the IRC. Under the 401k Plan, each participant may elect to defer taxation on a portion of his or her eligible earnings, as defined by the 401k Plan, by directing his or her employer to withhold a percentage of such earnings. A participating employee may also elect to make after-tax contributions to the 401k Plan. Under the 401k Plan, the employer may elect to match a percentage of each employee's qualifying annual compensation contributed to the 401k Plan on a pre-tax or Roth elective deferral basis. Participants are fully vested in any employer match immediately upon enrollment in the 401k Plan. During the years 2020 and 2019, we matched 100% of the first 5% of each employee’s qualifying annual compensation contributed to the 401k Plan; however, effective November 2020, we ceased matching contributions to the 401k Plan. For the Predecessor years ended December 31, 2020 and 2019, our provision for contributions was $6.2 million and $9.1 million, respectively. The defined contribution retirement plan for our U.K. employees provides that we make annual contributions in an amount equal to the employee's contributions generally up to a maximum percentage of the employee's defined compensation per year. Our contribution during 2021, 2020 and 2019 for employees working in the U.K. sector of the North Sea was 6% of the employee’s defined compensation. Our provision for contributions was $0.6 million, $0.3 million, $1.8 million and $2.1 million for the Successor period from April 24, 2021 through December 31, 2021 and the Predecessor periods from January 1, 2021 through April 23, 2021 and the years ended December 31, 2020 and 2019, respectively. Effective December 2020, we reduced our matching contribution to 4% of the employee’s defined compensation. The defined contribution retirement plan for our TCN employees (or the International Savings Plan) is similar to the 401k Plan. During the Predecessor years 2020 and 2019, we matched 5% of each employee’s compensation contributed to the International Savings Plan in each respective year. We ceased matching contributions to the International Savings Plan effective November 2020. Our provision for contributions to the plan was $0.2 million and $0.4 million for the Predecessor years ended December 31, 2020 and 2019, respectively. Deferred Compensation and Supplemental Executive Retirement Plan Our Amended and Restated Diamond Offshore Management Company Supplemental Executive Retirement Plan, or Supplemental Plan, provides benefits to a select group of our management or other highly compensated employees to compensate such employees for any portion of the applicable percentage of the base salary contribution and/or matching contribution under the 401k Plan that could not be contributed to that plan because of limitations within the Code. We ceased matching contributions to the Supplemental Plan effective January 2020. Our provision for contributions to the Supplemental Plan was $0.1 million for the Predecessor year ended December 31, 2019.

Employee Benefit Plans

12 Months Ended

Dec. 31, 2021

17. Employee Benefit Plans

Defined Contribution Plans

We maintain defined contribution retirement plans for our U.S., U.K., and third-country national (or TCN) employees. The plan for our U.S. employees (or the 401k Plan), is designed to qualify under Section 401(k) of the IRC. Under the 401k Plan, each participant may elect to defer taxation on a portion of his or her eligible earnings, as defined by the 401k Plan, by directing his or her employer to withhold a percentage of such earnings. A participating employee may also elect to make after-tax contributions to the 401k Plan. Under the 401k Plan, the employer may elect to match a percentage of each employee's qualifying annual compensation contributed to the 401k Plan on a pre-tax or Roth elective deferral basis. Participants are fully vested in any employer match immediately upon enrollment in the 401k Plan.

During the years 2020 and 2019, we matched 100% of the first 5% of each employee’s qualifying annual compensation contributed to the 401k Plan; however, effective November 2020, we ceased matching contributions to the 401k Plan. For the Predecessor years ended December 31, 2020 and 2019, our provision for contributions was $6.2 million and $9.1 million, respectively.

The defined contribution retirement plan for our U.K. employees provides that we make annual contributions in an amount equal to the employee's contributions generally up to a maximum percentage of the employee's defined compensation per year. Our contribution during 2021, 2020 and 2019 for employees working in the U.K. sector of the North Sea was 6% of the employee’s defined compensation. Our provision for contributions was $0.6 million, $0.3 million, $1.8 million and $2.1 million for the Successor period from April 24, 2021 through December 31, 2021 and the Predecessor periods from January 1, 2021 through April 23, 2021 and the years ended December 31, 2020 and 2019, respectively. Effective December 2020, we reduced our matching contribution to 4% of the employee’s defined compensation.

The defined contribution retirement plan for our TCN employees (or the International Savings Plan) is similar to the 401k Plan. During the Predecessor years 2020 and 2019, we matched 5% of each employee’s compensation contributed to the International Savings Plan in each respective year. We ceased matching contributions to the International Savings Plan effective November 2020. Our provision for contributions to the plan was $0.2 million and $0.4 million for the Predecessor years ended December 31, 2020 and 2019, respectively.

Deferred Compensation and Supplemental Executive Retirement Plan

Our Amended and Restated Diamond Offshore Management Company Supplemental Executive Retirement Plan, or Supplemental Plan, provides benefits to a select group of our management or other highly compensated employees to compensate such employees for any portion of the applicable percentage of the base salary contribution and/or matching contribution under the 401k Plan that could not be contributed to that plan because of limitations within the Code. We ceased matching contributions to the Supplemental Plan effective January 2020. Our provision for contributions to the Supplemental Plan was $0.1 million for the Predecessor year ended December 31, 2019.