XML 34 R20.htm IDEA: XBRL DOCUMENT
v3.21.2

Equity (Tables) - Equity Incentive Plan [Member] | 9 Months Ended
--- | ---
Sep. 30, 2021
2021 Employee Awards |
Schedule of weighted-average assumptions used in calculation of fair value of stock options | ​
​ | ​ | ​ | ​
2021 Employee Awards |  | 2021 | ​
Expected life |  | 5.75 | years
Weighted average volatility |  | 94 | %
Forfeiture rate |  | 0 | %
Weighted average risk-free interest rate |  | 0.47 | %
Expected dividend rate |  | 0 | %
2021 Director Awards |
Schedule of weighted-average assumptions used in calculation of fair value of stock options | ​
​ | ​ | ​ | ​
2021 Director Awards |  | 2021 | ​
Weighted average expected life | ​ | 8.93 | years
Weighted average volatility | ​ | 90 | %
Forfeiture rate | ​ | 0 | %
Weighted average risk-free interest rate | ​ | 1.02 | %
Expected dividend rate | ​ | 0 | %

X
- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_GranteeStatusAxis=us-gaap_ShareBasedPaymentArrangementEmployeeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=clir_EquityIncentivePlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GranteeStatusAxis=us-gaap_ShareBasedPaymentArrangementNonemployeeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |