Revenue Recognition (Narrative) (Details) T in Millions	Mar. 31, 2022 T
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations, fixed price contracts (in tons)	60.3
Remaining performance obligation, variable price contracts (in tons)	6.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations, fixed price contracts (in tons)	65.7
Remaining performance obligation, variable price contracts (in tons)	4.3