Financial Instruments and Other Guarantees (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Guarantee Obligations [Line Items]
Restricted Cash	$ 710.6	$ 680.9
Deposits Assets	125.4	276.7
Restricted cash and collateral	836.0	957.6
Surety Trust Account
Guarantee Obligations [Line Items]
Restricted Cash	413.5	444.0	$ 566.3
Deposits with Regulatory Authorities
Guarantee Obligations [Line Items]
Deposits Assets	125.4	276.7
Cash backed bank guarantees
Guarantee Obligations [Line Items]
Restricted Cash	297.1	$ 236.9
Asset Retirement Obligations
Guarantee Obligations [Line Items]
Surety bonds amount	962.1
Letters of credit outstanding, amount	53.6
Surety Bonds and Letters of Credit Outstanding for Reclamation Support	1,015.7
Less: Letters of Credit in Support of Surety Bonds	53.6
Total Obligations Supported, Net	962.1
Asset Retirement and Other Obligations
Guarantee Obligations [Line Items]
Surety bonds amount	1,070.3
Letters of credit outstanding, amount	152.1
Total Obligations Supported, Net	1,154.4
Total Surety Bonds and Letters of Credit Outstanding	1,222.4
Total Letters of Credit in Support of Surety Bonds	(68.0)
Other Obligations
Guarantee Obligations [Line Items]
Surety bonds amount	108.2
Letters of credit outstanding, amount	98.5
Less: Letters of Credit in Support of Surety Bonds	14.4
Total Obligations Supported, Net	192.3
Surety Bonds and Letters of Credit Outstanding for Other Support	206.7
Secured debt | Accounts Receivable Securitization Program
Guarantee Obligations [Line Items]
Letters of credit outstanding, amount	53.1
Letter of Credit
Guarantee Obligations [Line Items]
Letters of credit outstanding, amount	99.0
Collateralized Letter of Credit Agreement
Guarantee Obligations [Line Items]
Letters of credit outstanding, amount	$ 116.6