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Debt, Convertible Notes, and Warrants - Additional Information (Details) $ / shares in Units, $ in Thousands |  |  |  | 1 Months Ended | 12 Months Ended |  |  |  |
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Dec. 07, 2021 USD ($) shares | Jun. 05, 2020 USD ($) shares | Jun. 21, 2019 USD ($) agreement $ / shares shares | Jun. 30, 2019 USD ($) | Feb. 28, 2018 USD ($) | May 31, 2017 USD ($) agreement $ / shares | Nov. 30, 2014 USD ($) $ / shares shares | Jan. 31, 2022 USD ($) $ / shares shares | Jan. 31, 2021 USD ($) $ / shares shares | Jan. 31, 2020 USD ($) | Jul. 31, 2021 | Jan. 31, 2019 shares | Jan. 31, 2018 USD ($) shares | Jan. 31, 2017 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 9.3844 |  |  |  |  |  |
Debt extinguishment gain (loss) |  |  |  |  |  |  |  | $ (1,690) | $ 673 | $ (11,529) |  |  |  |
Amortization of debt discounts |  |  |  |  |  |  |  | $ 1,867 | 1,939 | $ 990 |  |  |  |
Warrant outstanding (in shares) | shares |  |  |  |  |  |  |  | 1,065,594 |  |  |  |  |  |
Common Class A |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  | $ 0.00001 |  |  |  |  |  |  |  |  |  |  |
Shares converted (in shares) | shares | 131,252,627 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in warrant exercise (in shares) | shares |  |  |  |  |  |  |  | 1,433,567 |  |  |  |  |  |
Warrant outstanding (in shares) | shares |  |  | 1,049,801 |  |  |  |  |  |  |  |  |  |  |
Common Class A | 2014 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares converted (in shares) | shares | 761,340 |  |  |  |  |  |  |  |  |  |  |  |  |
Common Class A | 2017 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in warrant exercise (in shares) | shares | 745,914 |  |  |  |  |  |  |  |  |  |  |  |  |
Common Class A | 2020 Convertible Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in warrant exercise (in shares) | shares | 27,713 |  |  |  |  |  |  |  |  |  |  |  |  |
Series D Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant outstanding (in shares) | shares | 450,205 |  |  |  |  |  |  | 1,065,594 |  |  |  |  |  |
Secured Debt | 2014 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  |  |  |  | $ 25,000 |  |  |  |  |  |  |
Debt stated rate |  |  |  |  |  |  | 11.00% |  |  |  |  |  |  |
Debt, unamortized discount |  |  |  |  |  |  | $ 600 |  |  |  |  |  |  |
Secured Debt | 2017 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt stated rate |  |  |  |  |  | 11.00% |  |  |  |  |  |  |  |
Debt, unamortized discount |  |  |  |  |  |  |  |  |  |  |  |  | $ 600 | $ 600
Proceeds from debt borrowings |  |  |  |  | $ 25,000 | $ 25,000 |  |  |  |  |  |  |  |
Number of instruments issued in debt agreement | agreement |  |  |  |  |  | 2 |  |  |  |  |  |  |  |
Principal payment of debt |  |  | $ 49,000 | $ 49,000 |  |  |  |  |  |  |  |  |  |
Debt extinguishment gain (loss) |  |  |  | (11,500) |  |  |  |  |  |  |  |  |  |
Amortization of debt discounts |  |  |  | 500 |  |  |  |  |  |  |  |  |  |
Secured Debt | 2017 Loans | Nominal Value |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt, net of discount |  |  |  | 8,600 |  |  |  |  |  |  |  |  |  |
Secured Debt | 2017 Loans | Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt, net of discount |  |  |  | $ 11,000 |  |  |  |  |  |  |  |  |  |
Secured Debt | Secured Term Loan A |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  |  |  | $ 25,000 |  |  |  |  |  |  |  |
Proceeds from debt borrowings |  |  |  |  | $ 12,500 | 12,500 |  |  |  |  |  |  |  |
Debt, net of discount |  |  | 49,000 |  |  |  |  |  |  |  |  |  |  |
Secured Debt | Secured Term Loan B |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  |  |  | 25,000 |  |  |  |  |  |  |  |
Proceeds from debt borrowings |  |  |  |  |  | $ 12,500 |  |  |  |  |  |  |  |
Principal payment of debt |  | $ 2,600 |  |  |  |  |  |  | 2,600 |  |  |  |  |
Debt extinguishment gain (loss) |  |  |  |  |  |  |  |  | $ 700 |  |  |  |  |
Debt, net of discount |  |  | $ 8,600 |  |  |  |  |  |  |  |  |  |  |
Subordinated contracts outstanding | agreement |  |  | 2 |  |  |  |  |  |  |  |  |  |  |
Subordinated contract liability |  |  | $ 4,300 |  |  |  |  |  |  |  |  |  |  |
Percent of consideration issuable in stock |  |  |  |  |  |  |  |  | 80.00% |  | 80.00% |  |  |
Shares issued in debt conversion (in shares) | shares | 754,378 |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant outstanding (in shares) | shares |  | 384,155 |  |  |  |  |  |  |  |  |  |  |  |
Percent of principal repaid |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |
Secured Debt | Secured Term Loan B | Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt, net of discount |  |  | 10,900 |  |  |  |  |  |  |  |  |  |  |
Secured Debt | Credit Agreement with SVB and Hercules |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  | $ 15,000 | $ 50,000 |  |  |  |  |  |  |  |  |  |  |
Debt stated rate |  | 11.00% | 11.00% |  |  |  |  |  |  |  |  |  |  |
Debt, variable rate floor |  |  | 11.00% |  |  |  |  |  |  |  |  |  |  |
Debt, unamortized discount |  | $ 1,600 | $ 4,200 |  |  |  |  |  |  |  |  |  |  |
Principal payment of debt | $ 67,100 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt extinguishment gain (loss) |  |  |  |  |  |  |  | $ (1,700) |  |  |  |  |  |
Loan fees associated with debt issuance |  |  | 300 |  |  |  |  |  |  |  |  |  |  |
Accrued loan fees payable |  | $ 600 | 1,500 |  |  |  |  |  |  |  |  |  |  |
Secured Debt | Credit Agreement with SVB and Hercules | Warrant |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt, unamortized discount |  |  | 4,200 |  |  |  |  |  |  |  |  |  |  |
Accrued loan fees payable |  |  | $ 1,800 |  |  |  |  |  |  |  |  |  |  |
Secured Debt | Series B Convertible Preferred Stock | 2014 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares called by warrants (in shares) | shares |  |  |  |  |  |  | 761,340 |  |  |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  |  |  |  | $ 9.3844 |  |  |  |  |  |  |
Secured Debt | Series D Convertible Preferred Stock | 2017 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares called by warrants (in shares) | shares |  |  |  |  |  |  |  |  |  |  |  | 372,957 | 372,957 |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  |  |  | $ 9.3844 |  |  |  |  |  |  |  |
Secured Debt | Prime Rate | 2014 Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt, variable rate spread |  |  |  |  |  |  | 7.75% |  |  |  |  |  |  |
Debt, variable rate floor |  |  |  |  |  |  | 11.00% |  |  |  |  |  |  |
Secured Debt | Prime Rate | Credit Agreement with SVB and Hercules |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt, variable rate spread |  |  | 5.50% |  |  |  |  |  |  |  |  |  |  |
Convertible notes | 2020 Convertible Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  |  |  |  |  |  | $ 71,100 |  |  |  |  |
Debt stated rate |  |  |  |  |  |  |  |  | 6.00% |  |  |  |  |
Change of control, repayment required |  |  |  |  |  |  |  |  | 200.00% |  |  |  |  |
Convertible debt, if converted, in excess of principal |  |  |  |  |  |  |  |  | $ 75,000 |  |  |  |  |
Conversion price, numerator for capitalization "capped price" |  |  |  |  |  |  |  |  | $ 2,500,000 |  |  |  |  |
Convertible notes | Common Class A | 2020 Convertible Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued in debt conversion (in shares) | shares | 9,824,143 |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible notes | Series D Convertible Preferred Stock | 2020 Convertible Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares called by warrants (in shares) | shares |  |  |  |  |  |  |  |  | 1,515,799 |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 9.3844 |  |  |  |  |
Warrants issued, percent of borrowings principal |  |  |  |  |  |  |  |  | 20.00% |  |  |  |  |

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- Definition Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1F -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495355-112611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 + Details
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- Definition Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644 + Details
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- Definition The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4313-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4304-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4332-108586 + Details
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- Definition The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4332-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4304-108586 + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031898-161870 + Details
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