Spire Global, Inc. Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation - Additional Information (Detail)

v3.23.3

Stock Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		9 Months Ended
	Jan. 01, 2023	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Proceeds from exercise of stock options		$ 0	$ 797
Number of options outstanding, Granted		61,446	0
weighted-average grant date fair value of options granted		$ 2.77
Restricted Stock Units (RSUs)
Defined Benefit Plan Disclosure [Line Items]
Unrecognized stock-based compensation expense		$ 25,180
Unrecognized stock-based compensation expense, weighted-average recognition period		2 years 2 months 23 days
2021 Equity Incentive Plan
Defined Benefit Plan Disclosure [Line Items]
Number of shares issued under share-based payment arrangement	897,996	490,623
2021 ESPP
Defined Benefit Plan Disclosure [Line Items]
Number of shares issued under share-based payment arrangement	179,599	603,349

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of shares issued under share-based payment arrangement.

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