The following tables show the Company’s cash equivalents and available-for-sale securities’ amortized cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category recorded as cash and cash equivalents or short- a (Details) - USD ($) |
Sep. 30, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|---|
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | $ 39,041,000 | $ 18,387,000 | $ 18,462,000 |
| Fair Value | 39,043,000 | 18,393,000 | 18,461,000 |
| Cash Equivalents | 33,138,000 | 9,424,000 | 8,761,000 |
| Gross Unrealized Gains | 3,000 | 7,000 | |
| Gross Unrealized Losses | (1,000) | (1,000) | (1,000) |
| Short-term Investments | 1,705,035 | 2,759,024 | 9,449,650 |
| Long-term Investments | 3,044,000 | 6,210,000 | 250,000 |
| Cash and Cash Equivalents [Member] | |||
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | 33,138,000 | 9,424,000 | 8,761,000 |
| Fair Value | 33,138,000 | 9,424,000 | 8,761,000 |
| Cash Equivalents | 33,138,000 | 9,424,000 | 8,761,000 |
| Cash and Cash Equivalents [Member] | Money Market Funds [Member] | |||
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | 33,138,000 | 9,424,000 | 8,761,000 |
| Fair Value | 33,138,000 | 9,424,000 | 8,761,000 |
| Cash Equivalents | 33,138,000 | 9,424,000 | 8,761,000 |
| Investments [Member] | |||
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | 5,903,000 | 8,963,000 | 9,701,000 |
| Fair Value | 5,905,000 | 8,969,000 | 9,700,000 |
| Gross Unrealized Gains | 3,000 | 7,000 | |
| Gross Unrealized Losses | (1,000) | (1,000) | (1,000) |
| Short-term Investments | 2,861,000 | 2,759,000 | 9,450,000 |
| Long-term Investments | 3,044,000 | 6,210,000 | 250,000 |
| Investments [Member] | Corporate Notes/Bonds [Member] | |||
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | 5,653,000 | 7,658,000 | 756,000 |
| Fair Value | 5,655,000 | 7,664,000 | 756,000 |
| Gross Unrealized Gains | 3,000 | 7,000 | |
| Gross Unrealized Losses | (1,000) | (1,000) | |
| Short-term Investments | 2,861,000 | 2,059,000 | 756,000 |
| Long-term Investments | 2,794,000 | 5,605,000 | |
| Investments [Member] | Convertible Debt Securities [Member] | |||
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | 250,000 | 605,000 | 250,000 |
| Fair Value | 250,000 | 605,000 | 250,000 |
| Long-term Investments | $ 250,000 | 605,000 | 250,000 |
| Investments [Member] | Commercial Paper [Member] | |||
| Debt Securities, Available-for-sale [Line Items] | |||
| Amortized Cost | 700,000 | 8,695,000 | |
| Fair Value | 700,000 | 8,694,000 | |
| Gross Unrealized Losses | (1,000) | ||
| Short-term Investments | $ 700,000 | $ 8,694,000 |
| X | ||||||||||
- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. No definition available.
|
| X | ||||||||||
- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. No definition available.
|
| X | ||||||||||
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|