Capital Stock - Summary of Convertible preferred stock (Details) - USD ($) $ / shares in Units, $ in Thousands |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
[1] | Dec. 31, 2018 |
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Temporary Equity [Line Items] | |||||||||||
| Net Carrying Value | [1] | $ 0 | $ 111,282 | ||||||||
| Seed | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 0.3275 | ||||||||||
| Shares Authorized | [2] | 3,895,772 | |||||||||
| Shares Issued | [2] | 3,895,771 | |||||||||
| Share Outstanding | [2] | 3,895,771 | |||||||||
| Net Carrying Value | $ 1,112 | ||||||||||
| Aggregate Liquidation Preference | $ 1,125 | ||||||||||
| Seed-1 | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 0.3036 | ||||||||||
| Shares Authorized | [2] | 8,860,187 | |||||||||
| Shares Issued | [2] | 8,860,185 | |||||||||
| Share Outstanding | [2] | 8,860,185 | |||||||||
| Net Carrying Value | $ 2,340 | ||||||||||
| Aggregate Liquidation Preference | $ 2,372 | ||||||||||
| Seed-2 | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 0.3624 | ||||||||||
| Shares Authorized | [2] | 3,755,433 | |||||||||
| Shares Issued | [2] | 3,755,433 | |||||||||
| Share Outstanding | [2] | 3,755,433 | |||||||||
| Net Carrying Value | $ 1,150 | ||||||||||
| Aggregate Liquidation Preference | $ 1,200 | ||||||||||
| Series A | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 0.5842 | ||||||||||
| Shares Authorized | [2] | 18,163,165 | |||||||||
| Shares Issued | [2] | 18,163,165 | |||||||||
| Share Outstanding | [2] | 18,163,165 | |||||||||
| Net Carrying Value | $ 9,316 | ||||||||||
| Aggregate Liquidation Preference | $ 9,356 | ||||||||||
| Series B | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 1.0413 | ||||||||||
| Shares Authorized | [2] | 16,718,570 | |||||||||
| Shares Issued | [2] | 16,337,364 | |||||||||
| Share Outstanding | [2] | 16,337,364 | |||||||||
| Net Carrying Value | $ 14,934 | ||||||||||
| Aggregate Liquidation Preference | $ 15,000 | ||||||||||
| Series C | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 1.5839 | ||||||||||
| Shares Authorized | [2] | 22,412,141 | |||||||||
| Shares Issued | [2] | 22,412,141 | |||||||||
| Share Outstanding | [2] | 22,412,141 | |||||||||
| Net Carrying Value | $ 31,226 | ||||||||||
| Aggregate Liquidation Preference | $ 31,300 | ||||||||||
| Series D | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Issue Price | $ 2.7515 | ||||||||||
| Shares Authorized | [2] | 21,903,878 | |||||||||
| Shares Issued | [2] | 21,158,491 | |||||||||
| Share Outstanding | [2] | 21,158,491 | |||||||||
| Net Carrying Value | $ 51,204 | ||||||||||
| Aggregate Liquidation Preference | $ 51,332 | ||||||||||
| Convertible Preferred Stock | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Share Outstanding | 0 | [1] | 94,582,550 | [1] | 94,582,550 | 73,424,071 | |||||
| Convertible Preferred Stock | Old Talkspace's | |||||||||||
| Temporary Equity [Line Items] | |||||||||||
| Shares Authorized | [2] | 95,709,146 | |||||||||
| Shares Issued | [2] | 94,582,550 | |||||||||
| Share Outstanding | [2] | 94,582,550 | |||||||||
| Net Carrying Value | $ 111,282 | ||||||||||
| Aggregate Liquidation Preference | $ 111,685 | ||||||||||
| |||||||||||