Leases - Sales-Type Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Net Investment in Lease [Abstract]
Sales-type Lease, Lease Receivable	$ 48,505	$ 49,806
Sales-type Lease, Unguaranteed Residual Asset	890	890
Sales-type Lease, Net Investment in Lease	49,395	50,696
Net Investment in Lease, Current	(5,515)	(5,428)
Net Investment in Lease, Noncurrent	43,880	45,268
Sales-type and Direct Financing Leases, Lease Receivable, Fiscal Year Maturity [Abstract]
Remainder of 2021	4,399
2022	6,110
2023	6,435
2024	6,797
2025	7,125
Thereafter	19,176
Total undiscounted cash flows	50,042
Less: imputed interest	(1,486)
Present value of lease payments	48,556
Lease receivable, current portion	5,500
Lease receivable, long-term portion	43,900
Current estimated credit losses	$ 100	$ 100

Sales-type and Direct Financing Leases, Lease Receivable, Long-term Portion

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Sales-type and Direct Financing Leases, Lease Receivable, Short-term Portion

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Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Four

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Amount of net investment in sales-type and direct financing lease, classified as current.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of net investment in sales-type and direct financing lease, classified as noncurrent.

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Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases.

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted lease receivable in excess of discounted receivable for sales-type and direct financing leases.

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Amount of net investment in sales-type lease.

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Amount of allowance for credit loss on net investment in sales-type lease.

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Present value expected to be derived from underlying asset following end of lease term not guaranteed by lessee or other third party unrelated to lessor.

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