Debt - Schedule of Outstanding Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Notes Principal Outstanding		$ 401
Net carrying amount		401
Less: current portion	$ 104	99	$ 7,791
Non-current portion	$ 223	302	1,555
Senior Notes
Debt Instrument [Line Items]
Net carrying amount		0	7,874
Less: current portion		0	6,459
Non-current portion		0	1,415
2017 Notes \| Senior Notes
Debt Instrument [Line Items]
Notes Principal Outstanding		0	5,304
Unamortized discount		0	(56)
2018 Notes \| Senior Notes
Debt Instrument [Line Items]
Notes Principal Outstanding		0	2,707
Unamortized discount		$ 0	$ (81)

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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.

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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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