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v3.21.2

Debt - Narrative (Details) | 6 Months Ended
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Jun. 30, 2021 USD ($) $ / shares | Jun. 30, 2020 USD ($)
Debt Instrument [Line Items] |  |
Total interest payments | $ 35,200,000 | $ 31,300,000
9% Convertible Junior Subordinated Debentures |  |
Debt Instrument [Line Items] |  |
Conversion rate (in shares per $1,000 note) | 0.0755932 |
Principal amount of notes used in determining conversion rate | $ 1,000 |
Convertible debt, conversion price (in dollars per share) | $ / shares | $ 13.23 |
Stated interest rate | 9.00% |
Senior Notes | 5.75% Senior Notes Due 2023 |  |
Debt Instrument [Line Items] |  |
Stated interest rate | 5.75% |
Senior Notes | 5.25% Senior Notes Due 2028 |  |
Debt Instrument [Line Items] |  |
Stated interest rate | 5.25% |

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