Income Taxes - Additional Information (Detail) - USD ($)
$ in Thousands |
12 Months Ended |
|
|
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Jan. 01, 2018 |
| Income Taxes [Line Items] |
|
|
|
|
| Increase in valuation allowance |
$ 25,200
|
$ 42,400
|
|
|
| Changes in ownership over period |
3 years
|
|
|
|
| Unrecognized tax benefits that would impact effective tax rate |
$ 0
|
0
|
|
|
| Accrued interest and penalties related to unrecognized tax benefits |
$ 0
|
0
|
$ 0
|
|
| Minimum [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Cumulative changes in ownership interest of shareholders |
50.00%
|
|
|
|
| Research and Development | California |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Business incentive tax credits to offset against taxes |
$ 6,600
|
|
|
|
| Research and Development | Massachusetts |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Business incentive tax credits to offset against taxes |
$ 1,200
|
|
|
|
| Tax credits, Expiration year |
2035
|
|
|
|
| Federal |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Net operating loss carryforwards |
$ 353,800
|
|
|
$ 303,200
|
| Net operating losses, Expiration year |
2035
|
|
|
|
| Business incentive tax credits to offset against taxes |
$ 10,990
|
|
|
|
| Tax credits, Expiration year |
2035 - 2040
|
|
|
|
| Federal | Research and Development |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Business incentive tax credits to offset against taxes |
$ 11,000
|
|
|
|
| Tax credits, Expiration year |
2035
|
|
|
|
| State |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Net operating loss carryforwards |
$ 347,184
|
$ 347,200
|
|
|
| Net operating losses, Expiration year |
2035 - 2040
|
|
|
|
| Net operating losses, Expiration year |
2035
|
|
|
|
| Business incentive tax credits to offset against taxes |
$ 7,806
|
|
|
|
| Tax credits, Expiration year |
CA: credits do not expireMA: 2035 - 2040
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