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Debt - Term Loans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended |
--- | --- | --- | ---
Aug. 31, 2020 | Mar. 31, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Line of Credit Facility [Line Items] |  |  |  |
Final payment fee |  | $ 2,300 |  |
Class of warrant or right, number of securities called by warrants or rights (in shares) | 196,850 |  |  |
Exercise price (in dollars per share) | $ 2.54 | $ 1.60 |  |
Class of warrant or right, expiration period | 10 years |  |  |
Adjustments to additional paid in capital, warrant issued | $ 400 |  |  |
2020 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Maximum borrowing capacity | 35,000 |  |  |
Debt instrument, additional accrued interest in the event of default |  | 0.050 |  |
Debt instrument, redemption price, percentage of principal amount redeemed |  | 9.00% |  |
Debt instrument, default, bankruptcy, or insolvency value of triggering accelerated redemption | 500 |  |  |
Debt issuance costs, line of credit arrangements (less than) | 400 |  |  |
Term loan facility |  | $ 25,000 |  | $ 25,000
Term A Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Maximum borrowing capacity | 25,000 |  |  |
Term B Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Maximum borrowing capacity | 10,000 |  |  |
2017 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Repayments of lines of credit | 13,700 |  |  |
Loss on extinguishment of debt |  |  | $ 500 |
Warrants to purchase common stock | Term B Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Sale common stock | $ 200,000 |  |  |
Maximum | 2020 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Debt instrument, prepayment fee, percentage |  | 0.030 |  |
Minimum | 2020 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Debt instrument, prepayment fee, percentage |  | 0.010 |  |
Debt Instrument, Redemption, Period One | 2020 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Basis spread on variable rate |  | 7.90% |  |
Debt Instrument, Redemption, Period Two | 2020 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Basis spread on variable rate |  | 4.65% |  |
Debt Instrument, Redemption, Period Three | 2020 Term Loans |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Basis spread on variable rate |  | 10.00% |  |

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- Definition Amount of increase in additional paid in capital (APIC) resulting from the issuance of warrants. Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109126253&loc=d3e4724-112606 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 + Details
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- Definition Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section S45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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