Borrowings - Debt and Equity Components and Issuance Costs of Convertible Notes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Equity component	$ 53,074	$ 83,127
2021 Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Debt component	143,645
Equity component	17,355
Equity issuance cost	$ 581
Stated interest rate	2.875%
Effective interest rate (as a percent)	4.70%
2022 Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Debt component	$ 137,266
Equity component	12,734
Equity issuance cost	$ 398
Stated interest rate	3.25%
Effective interest rate (as a percent)	5.20%
2023 Exchangeable Notes \| Exchangeable Notes Payable
Debt Instrument [Line Items]
Debt component	$ 157,971
Equity component	14,009
Equity issuance cost	$ 0
Stated interest rate	4.50%
Effective interest rate (as a percent)	6.50%
2025 Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Debt component	$ 91,024
Equity component	8,976
Equity issuance cost	$ 224
Stated interest rate	3.25%
Effective interest rate (as a percent)	5.00%

Debt Instrument, Convertible, Carrying Amount of Debt Component

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- Definition

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

+ References

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

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-Publisher FASB
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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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