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Debt - Schedule of Weighted Average Interest Rates (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Debt Instrument |  |  |
Interest expense | $ 43.8 | $ 29.5 | $ 17.6
NSM |  |  |
Debt Instrument |  |  |
Weighted Average | 276.0 | 274.2 |
Interest expense | $ 22.6 | $ 22.0 |
Weighted Average Interest rate | 8.20% | 8.00% |
NSM | Other Debt |  |  |
Debt Instrument |  |  |
Interest expense | $ 0.7 | $ 0.1 |
NSM | Designated as Hedging Instrument |  |  |
Debt Instrument |  |  |
Weighted Average | 146.9 | 148.4 |
Interest expense | $ 13.2 | $ 13.4 |
Weighted Average Interest rate | 9.00% | 9.00% |
NSM | Not Designated as Hedging Instrument |  |  |
Debt Instrument |  |  |
Weighted Average | $ 129.1 | $ 125.8 |
Interest expense | $ 9.4 | $ 8.6 |
Weighted Average Interest rate | 7.30% | 6.80% |

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