Other Assets - Other Asset Balances (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Other Assets [Abstract]
Prepaid Expenses	$ 67.0	$ 67.0
Right of use asset	39.0	57.0
Taxes receivable	34.0	32.0
Reimbursable amounts due from customers	18.0	11.0
Deferred contract costs	15.0	14.0
Marketable Securities	13.0	8.0
Favorable drilling and management services contracts	10.0	10.0
Insurance receivable	6.4	4.0
Other assets	30.0	37.0
Total other assets	232.0	$ 240.0
D&O insurance	$ 15.0
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Total other assets	Total other assets

Favorable Contracts

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- Definition

The reimbursable amounts due from customers, within one year of the balance sheet date (or the normal operating cycle, whichever is longer).

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No definition available.

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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- Definition

Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

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No definition available.

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Amount of investment in marketable security.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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Indicates line item in statement of financial position that includes operating lease right-of-use asset.

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Amount of assets classified as other.

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Amount due from parties in nontrade transactions, classified as other.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

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Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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