Spire Global, Inc. Quarterly report [Sections 13 or 15(d)]

Stock Based Compensation - Additional Information (Detail)

v3.25.3

Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 01, 2025	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Defined Benefit Plan Disclosure [Line Items]
Proceeds from exercise of stock options		$ 230	$ 2	$ 870	$ 269
Aggregate intrinsic value of options exercised in period		155	0	493	189
Fair value of options vested		$ 243	$ 922	$ 371	$ 1,686
Number of options outstanding, Granted		21,650	33,901	21,650	33,901
RSUs and PSUs
Defined Benefit Plan Disclosure [Line Items]
Fair value of options vested		$ 5,164	$ 1,847	$ 8,905	$ 4,343
Unrecognized stock-based compensation expense		$ 24,845		$ 24,845
Unrecognized stock-based compensation expense, weighted-average recognition period				2 years 2 months 12 days
2021 Equity Incentive Plan
Defined Benefit Plan Disclosure [Line Items]
Number of shares issued under share-based payment arrangement	1,285,558			1,247,439
2021 ESPP
Defined Benefit Plan Disclosure [Line Items]
Number of shares issued under share-based payment arrangement	257,111			803,675

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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