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Borrowings - Additional Information (Details) |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2018 USD ($) | Nov. 02, 2018 $ / shares | Sep. 30, 2018 | Jul. 31, 2019 USD ($) | Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) FinancingArrangement | Dec. 31, 2019 USD ($) | Jan. 01, 2019 USD ($) Installment | Oct. 26, 2017 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Lines of credit repaid principal amount |  |  |  |  |  | $ 123,000 |  |  |  |  |
Other Financing Arrangements |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of financing arrangements | FinancingArrangement |  |  |  |  |  |  |  | 3 |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  | $ 472,000 |  |  |
Debt instrument, discount |  |  |  |  | $ 298,000 |  |  |  |  |  |
Other Financing Arrangement One |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt instrument, maturity date |  |  |  |  | 2020-06 |  |  |  |  |  |
Other Financing Arrangement Two |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt instrument, maturity date |  |  |  |  | 2020-08 |  |  |  |  |  |
Loan and Security Agreement | East West Bank |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Maximum borrowings available |  |  |  |  |  |  |  | 8,000,000 |  |  |
Outstanding borrowings |  |  |  |  | $ 0 |  |  |  | $ 0 |  |
Line of credit facility, covenant compliance minimum required availability amount | $ 1,200,000 |  |  |  |  |  | $ 1,200,000 | $ 750,000 |  |  |
Fixed charge coverage ratio for last day of each month | 1.10 |  | 1.05 |  |  |  |  |  |  |  |
Line of credit facility, status of covenant compliance |  |  |  |  | the Company was not in compliance with one of the financial covenants, specifically the fixed charge coverage ratio, however, the Senior Lender waived such noncompliance in October 2019 by amending the EWB Loan Agreement through February 2020. The Senior Lender subsequently extended the waiver and maturity date to June 2020. |  |  |  |  |  |
Waiver extended date |  |  |  |  | 2020-06 |  |  |  |  |  |
Loan and Security Agreement | East West Bank | Prime Lending Rate |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, spread on variable interest |  |  |  |  | 1.00% |  |  |  |  |  |
Loan and Security Agreement | East West Bank | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Remaining borrowing capacity |  |  |  |  | $ 8,000,000 |  |  |  | 8,000,000 |  |
Fixed charge coverage ratio for last day of each month |  |  |  |  |  |  |  | 1.05 |  |  |
Loan and Security Agreement | East West Bank | Minimum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Fixed charge coverage ratio for last day of each month |  |  |  |  |  |  |  | 1.00 |  |  |
Subordinated Term Loan and Security Agreement | B. Riley Principal Investments, LLC |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Maximum borrowings available | $ 12,000,000 |  |  |  |  |  | 12,000,000 |  |  |  | $ 10,000,000
Outstanding borrowings |  |  |  |  | 10,258,000 |  |  |  | 10,003,000 |  |
Minimum principal amount outstanding to have waiver of defined prepayment penalties | $ 10,000,000 |  |  |  |  |  | $ 10,000,000 |  |  |  |
Interest rate, stated percentage | 10.00% |  |  |  |  |  | 10.00% |  |  |  |
Line of credit facility, maturity date |  |  |  |  |  |  | Sep. 01, 2022 |  |  |  |
Lines of credit repaid principal amount |  |  |  | $ 3,250,000 |  |  |  |  |  |  |
Lines of credit repaid principal amount percentage |  |  |  | 25.00% |  |  |  |  |  |  |
Percentage of fee incurred |  |  |  | 2.00% |  |  |  |  |  |  |
Compounded interest |  |  |  |  | 255,000 |  |  |  |  |  |
Debt instrument, convertible, price of common stock per share | $ / shares |  | $ 8.87 |  |  |  |  |  |  |  |  |
Subordinated Term Loan and Security Agreement | B. Riley Principal Investments, LLC | Prior to First Anniversary of Effective Date |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Designated percentage |  | 100.00% |  |  |  |  |  |  |  |  |
Subordinated Term Loan and Security Agreement | B. Riley Principal Investments, LLC | Year Two of Loan Agreement |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Designated percentage |  | 75.00% |  |  |  |  |  |  |  |  |
Subordinated Term Loan and Security Agreement | B. Riley Principal Investments, LLC | Year Three of Loan Agreement |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Designated percentage |  | 50.00% |  |  |  |  |  |  |  |  |
Subordinated Term Loan and Security Agreement | B. Riley Principal Investments, LLC | Year Four of Loan Agreement |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Designated percentage |  | 25.00% |  |  |  |  |  |  |  |  |
Subordinated Term Loan and Security Agreement | B. Riley Principal Investments, LLC | Final Year of Agreement on or Prior to Maturity Date |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Designated percentage |  | 12.50% |  |  |  |  |  |  |  |  |
Promissory Notes Payable |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt instrument, outstanding balance |  |  |  |  | $ 472,000 |  |  |  | $ 508,000 | $ 736,000 |
Debt instrument, periodic payment, number of equal quarterly installments | Installment |  |  |  |  |  |  |  |  |  | 20 |
Debt instrument, frequency of periodic payment |  |  |  |  | quarterly |  |  |  |  |  |
Promissory Notes Payable | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Interest rate, stated percentage |  |  |  |  | 8.00% |  |  |  |  |  |
Debt instrument, payment term |  |  |  |  | 4 years |  |  |  |  |  |
Promissory Notes Payable | Minimum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt instrument, payment term |  |  |  |  | 2 years |  |  |  |  |  |

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