Unsecured Senior Notes - Convertible Notes (Details)	12 Months Ended
Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares
Unsecured Senior Notes
Principal amount of notes, basis for conversion \| $	$ 1,000
Closing share price (in dollars per share)	$ 24.30	$ 19.30	$ 24.86
2023 Convertible Notes
Unsecured Senior Notes
Conversion Rate	38.5959
Conversion price (in dollars per share)	$ 25.91

The principal amount of the convertible debt instrument used as the basis for the conversion ratio.

No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Details

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