Spire Global (SPIR) 10-Q 10 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Nov. 10, 2021
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Entity Registrant Name	Spire Global, Inc.
Entity Central Index Key	0001816017
Document Period End Date	Sep. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-39493
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	85-1276957
Entity Address, Address Line One	8000 Towers Crescent Drive
Entity Address, Address Line Two	Suite 1225
Entity Address, City or Town	Vienna
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	22182
City Area Code	202
Local Phone Number	301-5127
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Interactive Data Current	Yes
Common Class A [Member]
Document Information [Line Items]
Title of 12(b) Security	Class A common stock, par value of $0.0001 per share
Trading Symbol	SPIR
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		133,830,621
Common Class B [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		12,058,614
Warrant [Member]
Document Information [Line Items]
Title of 12(b) Security	Warrants, each whole warrant exercisable for one share of Class A common stock at an exercise price of $11.50 per share
Trading Symbol	SPIR.WS
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		18,099,992

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 245,770	$ 15,571
Accounts receivable, net (including allowance of $389 and $174 as of September 30, 2021 and December 31, 2020, respectively)	6,456	3,738
Contract assets	1,089	853
Restricted cash, current	12,801	0
Other current assets	10,227	2,112
Total current assets	276,343	22,274
Property and equipment, net	25,855	20,458
Other long-term assets, including restricted cash	1,365	1,690
Total assets	303,563	44,422
Current liabilities
Accounts payable	4,738	1,775
Accrued wages and benefits	1,865	1,590
Contract liabilities, current portion	10,331	8,110
Warrant liability, current portion	22,582	0
Other accrued expenses	5,967	1,813
Total current liabilities	45,483	13,288
Long-term debt, non-current	45,221	26,645
Contingent earnout liability	77,131	0
Convertible notes payable, net (including related parties of $0 and $7,498 as of September 30, 2021, and December 31, 2020, respectively)	0	48,631
Deferred income tax liabilities	287	338
Warrant liability	30,770	4,007
Other long-term liabilities	1,382	249
Total liabilities	200,274	93,158
Commitments and contingencies (Note 9)
Stockholders' Equity (Deficit)
Common Stock	15	2
Additional paid-in capital	393,872	10,131
Accumulated other comprehensive loss	(191)	(982)
Accumulated deficit	(290,407)	(211,146)
Total stockholders' equity (deficit)	103,289	(48,736)
Total liabilities and stockholders' equity (deficit)	303,563	44,422
Series A Preferred Stock [Member]
Stockholders' Equity (Deficit)
Preferred Stock	0	52,809
Series B Preferred Stock [Member]
Stockholders' Equity (Deficit)
Preferred Stock	0	35,228
Series C preferred stock [Member]
Stockholders' Equity (Deficit)
Preferred Stock	$ 0	$ 65,222

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts Receivable, Allowance for Credit Loss, Current	$ 389	$ 174
Notes Payable, Related Parties, Noncurrent	$ 0	$ 7,498
Common stock per share	$ 0.0001
Series A Preferred Stock [Member]
Preferred stock, Par value	$ 0.0001	$ 0.0001
Preferred stock, authorized	0	12,671,911
Preferred stock, issued	0	21,615,723
Preferred stock, outstanding	0	21,615,723
Preferred Stock, Liquidation Preference, Value		$ 52,809
Series B Preferred Stock [Member]
Preferred stock, Par value	$ 0.0001	$ 0.0001
Preferred stock, authorized	0	4,869,754
Preferred stock, issued	0	8,306,818
Preferred stock, outstanding	0	8,306,818
Preferred Stock, Liquidation Preference, Value		$ 35,228
Series C preferred stock [Member]
Preferred stock, Par value	$ 0.0001	$ 0.0001
Preferred stock, authorized	0	9,126,525
Preferred stock, issued	0	12,804,176
Preferred stock, outstanding	0	12,804,176
Preferred Stock, Liquidation Preference, Value		$ 65,222
Common Class A [Member]
Common stock per share	$ 0.0001	$ 0.0001
Common stock, authorized	1,000,000,000	55,000,000
Common stock, Issued	133,742,534	17,664,015
Common stock, outstanding	133,742,534	17,664,015
Common Class B [Member]
Common stock per share	$ 0.0001	$ 0.0001
Common stock, authorized	15,000,000	55,000,000
Common stock, Issued	12,058,614
Common stock, outstanding	12,058,614

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue	$ 9,561	$ 7,184	$ 28,390	$ 21,221
Cost of revenue	5,338	2,426	12,393	7,821
Gross profit	4,223	4,758	15,997	13,400
Operating expenses
Research and development	7,804	5,231	21,913	14,585
Sales and marketing	5,574	2,294	14,369	7,082
General and administrative	8,217	3,110	23,507	8,854
Loss on satellite deorbit and launch failure	0	666	0	666
Total operating expenses	21,595	11,301	59,789	31,187
Loss from operations	(17,372)	(6,543)	(43,792)	(17,787)
Other income (expense)
Interest income	4	0	6	45
Interest expense	(2,392)	(1,522)	(8,267)	(4,479)
Change in fair value of warrant liabilities	(13,353)		(23,529)
Other income (expense), net	681	636	(2,710)	181
Total other income (expense), net	(15,060)	(886)	(34,500)	(4,253)
Loss before income taxes	(32,432)	(7,429)	(78,292)	(22,040)
Income tax provision	269	195	969	300
Net loss	$ (32,701)	$ (7,624)	$ (79,261)	$ (22,340)
Basic and diluted net loss per share (Class A common stock)	$ (0.49)	$ (0.43)	$ (2.12)	$ (1.27)
Weighted-average shares of Class A common stock used in computing basic and diluted net loss per share	67,348,269	17,605,469	37,389,424	17,603,874

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net loss	$ (32,701)	$ (7,624)	$ (79,261)	$ (22,340)
Other comprehensive loss:
Foreign currency translation adjustments	324	(94)	791	30
Comprehensive loss	$ (32,377)	$ (7,718)	$ (78,470)	$ (22,310)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) - USD ($) $ in Thousands		Total	Series A Preferred Stock [Member]	Series B Preferred Stock [Member]	Series C Preferred Stock [Member]	Preferred Stock [Member]Series A Preferred Stock [Member]	Preferred Stock [Member]Series B Preferred Stock [Member]	Preferred Stock [Member]Series C Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member]Series A Preferred Stock [Member]	Common Stock [Member]Series B Preferred Stock [Member]	Common Stock [Member]Series C Preferred Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Series A Preferred Stock [Member]	Additional Paid-in Capital [Member]Series B Preferred Stock [Member]	Additional Paid-in Capital [Member]Series C Preferred Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2019		$ (18,655)	$ 52,809	$ 35,228	$ 65,222				$ 2				$ 7,354				$ (628)	$ (178,642)
Beginning balance, shares at Dec. 31, 2019	[1]		21,615,723	8,306,818	12,804,176				17,602,594
Exercise of stock options		6											6
Exercise of stock options, shares	[1]								4,351
Stock compensation expense		1,451											1,451
Net loss		(22,340)																(22,340)
Foreign currency translation adjustments		30															30
Ending balance at Sep. 30, 2020		(39,508)	$ 52,809	$ 35,228	$ 65,222				$ 2				8,811				(598)	(200,982)
Ending balance, shares at Sep. 30, 2020	[1]		21,615,723	8,306,818	12,804,176				17,606,945
Beginning balance at Jun. 30, 2020		(32,325)	$ 52,809	$ 35,228	$ 65,222				$ 2				8,276				(504)	(193,358)
Beginning balance, shares at Jun. 30, 2020	[1]		21,615,723	8,306,818	12,804,176				17,604,528
Exercise of stock options		4											4
Exercise of stock options, shares	[1]								2,417
Stock compensation expense		531											531
Net loss		(7,624)																(7,624)
Foreign currency translation adjustments		(94)															(94)
Ending balance at Sep. 30, 2020		(39,508)	$ 52,809	$ 35,228	$ 65,222				$ 2				8,811				(598)	(200,982)
Ending balance, shares at Sep. 30, 2020	[1]		21,615,723	8,306,818	12,804,176				17,606,945
Beginning balance at Dec. 31, 2020		(48,736)				$ 52,809	$ 35,228	$ 65,222	$ 2				10,131				(982)	(211,146)
Beginning balance, shares at Dec. 31, 2020	[1]					21,615,723	8,306,818	12,804,176	17,664,015
Exercise of stock options		1,065											1,065
Exercise of stock options, shares	[1]								799,901
Stock compensation expense		6,600											6,600
Issuance of shares to FP Lenders (Note 6)		22,868							$ 1				22,868
Issuance of shares to FP Lenders (Note 6), shares	[1]								2,468,492
Conversion of warrants to common stock		308											308
Conversion of warrants to common stock, shares	[1]								672,355
Conversion of convertible notes to common stock		70,933	$ 52,807	$ 35,227	$ 66,112	$ (52,809)	$ (35,228)	$ (66,113)	$ 4	$ 2	$ 1	$ 1	70,929
Conversion of convertible notes to common stock, shares	[1]		21,615,723	8,306,818	12,951,095	(21,615,723)	(8,306,818)	(12,951,095)	37,034,620
Issuance of common stock upon the reverse recapitalization, net of issuance costs		206,224							$ 4				206,220
Issuance of common stock upon the reverse recapitalization, net of issuance costs, shares	[1]								44,288,129
Contingent earnout liability upon closing of the merger		(78,395)											(78,395)
Exercise of series C preferred warrants					$ 891			$ 891
Exercise of series C preferred warrants, shares	[1]							146,919
Net loss		(79,261)																(79,261)
Foreign currency translation adjustments		791															791
Ending balance at Sep. 30, 2021		103,289				$ 0	$ 0	$ 0	$ 15				393,872				(191)	(290,407)
Ending balance, shares at Sep. 30, 2021	[1]					0	0	0	145,801,148
Beginning balance at Jun. 30, 2021		(80,699)				$ 52,809	$ 35,228	$ 66,113	$ 2				23,370				(515)	(257,706)
Beginning balance, shares at Jun. 30, 2021	[1]					21,615,723	8,306,818	12,951,095	19,212,323
Exercise of stock options		392											392
Exercise of stock options, shares	[1]								229,316
Stock compensation expense		2,099											2,099
Issuance of shares to FP Lenders (Note 6)		14,804							$ 1				14,803
Issuance of shares to FP Lenders (Note 6), shares	[1]								1,490,769
Conversion of warrants to common stock		308											308
Conversion of warrants to common stock, shares	[1]								672,355
Conversion of convertible notes to common stock		70,933				$ (52,809)	$ (35,228)	$ (66,113)	$ 4	$ 2	$ 1	$ 1	70,929	$ 52,807	$ 35,227	$ 66,112
Conversion of convertible notes to common stock, shares	[1]					(21,615,723)	(8,306,818)	(12,951,095)	37,034,620	21,615,723	8,306,818	12,951,095
Issuance of common stock upon the reverse recapitalization, net of issuance costs		206,224							$ 4				206,220
Issuance of common stock upon the reverse recapitalization, net of issuance costs, shares	[1]								44,288,129
Contingent earnout liability upon closing of the merger		(78,395)											(78,395)
Net loss		(32,701)																(32,701)
Foreign currency translation adjustments		324															324
Ending balance at Sep. 30, 2021		$ 103,289				$ 0	$ 0	$ 0	$ 15				$ 393,872				$ (191)	$ (290,407)
Ending balance, shares at Sep. 30, 2021	[1]					0	0	0	145,801,148
[1]	The shares of the Company’s common and convertible preferred stock, prior to the Merger (as defined in Note 1) have been retroactively restated to reflect the exchange ratio of approximately 1.7058 established in the Merger as described in Note 3.

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) (Parenthetical)	Sep. 30, 2021shares
Common Class B [Member]
Common stock, outstanding	12,058,614

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Net loss	$ (79,261)	$ (22,340)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,615	3,861
Stock-based compensation	6,600	1,451
Accretion on carrying value of convertible notes	2,103	3,333
Amortization of debt issuance costs	2,617	158
Change in fair value of warrant liability	23,529
Change in fair value of contingent earnout liability	(1,265)
Deferred income tax liabilities	(47)	193
Loss on extinguishment of debt	2,277
Loss on impairment of intangible assets	91
Changes in operating assets and liabilities:
Accounts receivable	(2,905)	534
Contract assets	(250)	(575)
Other current assets	(7,381)	(492)
Other long-term assets	213	(152)
Accounts payable	1,118	1,182
Accrued wages and benefits	302	734
Contract liabilities	2,416	3,369
Other accrued expenses	1,536	833
Other long-term liabilities	2,684	(509)
Net cash used in operating activities	(40,008)	(8,420)
Cash flows from investing activities
Purchase of property and equipment	(9,309)	(8,240)
Investment in intangible assets	(140)	(67)
Net cash used in investing activities	(9,449)	(8,307)
Cash flows from financing activities
Proceeds from reverse recapitalization and PIPE financing	264,823
Payments of transaction costs related to reverse recapitalization	(30,600)
Proceeds from long-term debt	70,000	7,592
Proceeds from issuance of convertible notes payable	20,000	250
Payments on redemption of long-term debt	(29,628)	(4,500)
Payment of debt issuance costs	(4,293)	(183)
Proceeds from exercise of stock options	1,065	6
Net cash provided by financing activities	291,367	3,165
Effect of foreign currency translation on cash, cash equivalent and restricted cash	1,071	236
Net increase (decrease) in cash, cash equivalents and restricted cash	242,981	(13,326)
Cash, cash equivalents and restricted cash
Beginning of period	15,986	24,531
End of period	258,967	11,205
Supplemental disclosure of cash flow information
Cash paid for interest	1,431	878
Cash paid for income taxes	233
Noncash financing activities
Conversion of Series A, B and C preferred stock to common stock upon the reverse recapitalization	154,150
Contingent earnout liability recognized upon the closing of the reverse recapitalization	78,395
Conversion of convertible notes to common stock upon the reverse recapitalization	70,933
Public and private warrants acquired as part of the merger	26,707
Issuance of shares to FP (Note 6)	22,868
Capitalized merger and acquisition costs not yet paid	2,146
Property and equipment purchased but not yet paid	1,924
Exercise of Series C preferred stock warrants	891
Issuance of stock warrants with long-term debt	$ 308	$ 1,806

Nature of Business

Nature of Business	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	1. Nature of Business Spire Global, Inc. (“Spire” or the “Company”), founded in August 2012, is a global provider of space-based data and analytics that offers its customers unique datasets and insights about earth from the ultimate vantage point. The Company collects this space-based data through its proprietary constellation of multi-purpose nanosatellites. By designing, manufacturing, integrating and operating its own satellites and ground stations, the Company has unique end-to-end “space-as-a-service” The Company is comprised of Spire Global, Inc. (“United States” or “U.S.”) and its wholly owned subsidiaries: Spire Global Subsidiary, Inc., Spire Global UK Limited (“United Kingdom or U.K”.), Spire Global Luxembourg S.a.r.l. (“Luxembourg”), Spire Global Singapore Pte. Ltd. (“Singapore”) and Spire Global Canada Acquisition Corp. The Company currently operates offices in six locations: San Francisco, Boulder, Washington D.C. (U.S.), Glasgow (U.K.), Luxembourg, and Singapore. On August 16, 2021 (the “Closing Date”), Spire Global Subsidiary, Inc. (formerly known as Spire Global, Inc.) (“Old Spire”) closed its previously announced merger with NavSight Holdings, Inc. (“NavSight”), a special purpose acquisition company, pursu a Please refer to Note 3 “Reverse Recapitalization” for further details of the Merger. On September 13, 2021, the Company entered into a definitive agreement with exactEarth Ltd., a Canadian corporation (“exactEarth”), and leading provider of global maritime vessel data for ship tracking and maritime situational awareness solutions, pursuant to which the Company will acquire exactEarth for an estimated purchase price of approximately $161.2 million, consisting of (i) $103.4 million in cash on hand, and (ii) $57.8 million of shares of the Company’s Class A common stock (or approximately 5,234,857 shares), in each case upon the terms and subject to the conditions of the definitive agreement. The proposed acquisition (the “Proposed Acquisition”) is subject to customary closing conditions, including the receipt of certain regulatory approvals; the approval of the Ontario Superior Court of Justice (Commercial List); the approval by not less than two-thirds of the votes cast at a special meeting of exactEarth shareholders, which will take place on November 18, 2021; no material adverse effect having occurred in respect of either the Company or exactEarth; and dissent rights not having been exercised with respect to more than 10% of exactEarth’s outstanding common shares. The Proposed Acquisition is expected to close in the fourth quarter of 2021 or the first quarter of 2022. On October 15, 2021, the Company and exactEarth amended the definitive agreement to the Plan of Arrangement to cause consideration that is unclaimed after two years to continue to be administered by the depositary, instead of being returned for further administration by the Company.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The condensed consolidated financial statements and accompanying notes are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and regulations of the U.S. Securities and Exchange Commission for interim financial reporting. The condensed consolidated financial statements for the three and nine months ended September 30, 2021 include the accounts of Spire Global, Inc. (i.e. former NavSight) and its wholly-owned subsidiary, Old Spire, following the Reverse Recapitalization as further discussed in Note 3 “Reverse Recapitalization.” For periods prior to the Merger, the reported share and per share amounts have been retroactively converted by applying the Exchange Ratio with the exception of authorized shares. Issued and outstanding shares and warrants as disclosed herein have been adjusted reflecting the Exchange Ratio. All other accompanying financial statements as of December 31, 2020 and for the three and nine months ended September 30, 2020 include only the accounts of Old Spire. Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the related notes for the years ended December 31, 2020 and 2019. The information as of December 31, 2020 included on the condensed consolidated balance sheets was derived from the Company’s audited consolidated financial statements. The unaudited condensed consolidated financial statements were prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, contain all adjustments, consisting of normal recurring adjustments necessary for a fair statement of its financial position, results of operations and cash flows for the periods indicated. All intercompany accounts and transactions have been eliminated in consolidation. Operating results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for any other interim period or for the year ending December 31, 2021. Liquidity Risks and Uncertainties The unaudited condensed consolidated financial statements have been prepared on the basis of continuity of operations, the realization of assets, and the satisfaction of liabilities in the ordinary course of business. Since inception, the Company has been engaged in developing its product offerings, raising capital, and recruiting personnel. The Company’s operating plan may change as a result of many factors currently unknown and there can be no assurance that the current operating plan will be achieved in the time frame anticipated by the Company, and it may need to seek additional funds sooner than planned. If adequate funds are not available to the Company on a timely basis, it may be required to delay, limit, reduce, or terminate certain commercial efforts, or pursue merger or acquisition strategies, all of which could adversely affect the holdings or the rights of the Company’s stockholders. The Company has a history of operating losses and negative cash flows from operations since inception. During the nine months ended September 30, 2021, net loss was $79,261 and cash used in operations was $40,008. During the nine months ended September 30, 2020, net loss was $22,340 and cash used in operations was $8,420. The Company held cash and cash equivalents of $245,770, excluding restricted cash, at September 30, 2021. On August 16, 2021, the Company received net proceeds of approximately $236,632 from Private Investment in Public Equity (“PIPE”) The Company’s assessment of the period of time through which its financial resources will be adequate to support its operations is a forward-looking statement and involves risks and uncertainties. The Company’s actual results could vary as a result of many factors, including its growth rate, subscription renewal activity, the timing and extent of spending to support its infrastructure and research and development efforts and the expansion of sales and marketing activities. The Company may in the future enter into arrangements to acquire or invest in complementary businesses, services, and technologies, including intellectual property rights. The Company has based its estimates on assumptions that may prove to be wrong, and it could use its available capital resources sooner than it currently expects. The Company may be required to seek additional equity or debt financing. Future liquidity and cash requirements will depend on numerous factors, including market penetration, the introduction of new products, and potential acquisitions of related businesses or technology. In the event that additional financing is required from outside sources, the Company may not be able to raise it on acceptable terms or at all. If the Company is unable to raise additional capital when desired, or if it cannot expand its operations or otherwise capitalize on its business opportunities because it lacks sufficient capital, its business, operating results, and financial condition would be adversely affected. COVID-19 In March 2020, the World Health Organization declared the outbreak of COVID-19 shelter-in-place COVID-19 day-to-day COVID-19 COVID-19 COVID-19 COVID-19 re-work COVID-19 Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the dates of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. Management’s significant estimates include assumptions in revenue recognition, contingent earnout liability, allowance for doubtful accounts, realizability of deferred income tax assets, equity awards and warrant liabilities. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment. The Company adjusts such estimates and assumptions based on the facts and circumstances. As future events and their effects cannot be determined with precision, actual results could differ from those estimates. Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Restricted cash, current and restricted cash included in Other long-term assets in the Condensed Consolidated Balance Sheets represents amounts pledged as guarantees or collateral for financing arrangements (Note 6 and Note 12) and lease agreements, as contractually required. The following table shows components of cash, cash equivalents, and restricted cash reported on the Condensed Consolidated Balance Sheets and in the Condensed Consolidated Statements of Cash Flows as of: September 30, December 31, Cash and cash equivalents $ 245,770 $ 15,571 Restricted cash, current 12,801 — Restricted cash included in Other long-term assets 396 415 $ 258,967 $ 15,986 Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash, cash equivalents and restricted cash, and accounts receivable. The Company typically has cash account balances in excess of Federal Deposit Insurance Corporation insurance coverage. The Company has not experienced any losses on such accounts, and management believes that the Company’s risk of loss is remote. The Company has a concentration of contractual revenue arrangements with governmental agencies and nongovernmental entities. Entities under common control are reported as a single customer. As of September 30, 2021, the Company had three customers that accounted for 21%, 19% and 12% of the Company’s total account receivable and as of December 31, 2020, the Company had one customer that accounted for 67% of the Company’s total accounts receivable. The Company had the following customers whose revenue balances individually represented 10% or more of the Company’s total revenue: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Customer A 18 % 24 % 27 % 35 % Customer B 17 % 20 % 19 % 21 % Customer C * 16 % 11 % 10 % * Revenue from these customers were less than 10% of total revenue during the period. Deferred Offering and Merger Costs The Company capitalizes within Other current assets on the Condensed Consolidated Balance Sheets certain legal, accounting and other third-party fees that are directly related to the Company’s in-process of such costs as of September 30, 2021. As of the Closing, these capitalized merger costs were recorded to Additional paid-in capital on the Condensed Consolidated Balance Sheet (Note 3). During the nine months ended September 30, 2021, the Company incurred an additional $6,591 of costs indirectly related to the Merger, including of other merger related costs. These amounts have been included in General and administrative expenses in the Condensed Consolidated Statements of Operations for the nine months ended September 30, 2021. No such costs were incurred during the nine months ended September 30, 2020. Related Parties One of the Company’s stockholders and debtors is also a customer from which the Company generated $606 of revenue for the nine months ended September 30, 2020. No revenue was generated from this customer for the nine months ended September 30, 2021. The Company borrowed gross proceeds of $1,232 of Convertible notes payable in February 2021 and $6,414 of Convertible notes payable during the year ended December 31, 2019, from certain stockholders (Note 7). Interest expense recognized on related party Convertible notes payable was $89 and $413 for the three and nine months ended September 30, 2021, respectively, and Immediately prior to the effective time of the Merger, the Convertible Notes were automatically converted into shares of common stock of Old Spire (“Old Spire Common Stock”) (Note 3 and Note 7). Total carrying value of the related party balance included as Convertible notes payable, net on the Condensed Consolidated Balance Sheets was Common Stock Warrants The Company assumed 11,499,992 c 0.0001 11.50 non-redeemable The Company evaluated the Common Stock Warrants and concluded that they do not meet the criteria to be classified within stockholders’ equity. The agreement governing the Common Stock Warrants includes a provision that could result in a different settlement value for the Common Stock Warrants depending on their holder. Because the holder of an instrument is not an input into the pricing of a fixed-for-fixed 50 Contingent Earnout Liability In connection with the Reverse Recapitalization and pursuant to the Merger Agreement, eligible Spire equity holders are entitled to receive additional shares of the Company’s Common Stock upon the Company achieving certain Earnout Triggering Events (as described in the Merger Agreement and Note 3). In accordance with ASC 815-40, The contingent earnout liability is categorized as a Level 3 fair value measurement using the Monte Carlo model (Note 8) because the Company estimates projections during the Earnout Period utilizing unobservable inputs. Contingent earnout payments involve certain assumptions requiring significant judgment and actual results may differ from assumed and estimated amounts. Accounting Pronouncements Recently Adopted In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-13, Financial Instruments—Credit Losses (Topic 326) Measurement of Credit Losses on Financial Instruments 2016-13 2016-13 In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal Use Software (Subtopic 350-40): 2018-15 In March 2020 and January 2021, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting 2021-01, Reference Rate Reform (Topic 848) 2020-04 2021-01 Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) right-of-use In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes non-income-based In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805), Accounting for Contract Assets and Contract Liabilities from Contracts with Customers

Reverse Recapitalization

Reverse Recapitalization	9 Months Ended
	Sep. 30, 2021
Business Combinations [Abstract]
Reverse Recapitalization	3. Reverse Recapitalization Immediately prior to the Closing: • All 12,671,911 outstanding shares of Old Spire Series A Convertible Preferred Stock were converted into an equivalent number of shares of Old Spire Common Stock on a one-to-one . • All 4,869,754 outstanding shares of Old Spire Series B Convertible Preferred Stock were converted into an equivalent number of shares of Old Spire Common Stock on a one-to-one . • All 7,592,402 outstanding shares of Old Spire Series C Convertible Preferred Stock were converted into an equivalent number of shares of Old Spire Common Stock on a one-to-one . • Each of the Convertible Notes (as defined in Note 6) automatically converted into shares of Old Spire Common Stock. The conversion ratio for the 2019 and 2020 Convertible Notes (as defined in Note 6) was and the conversion ratio for the 2021 Convertible Notes (as defined in Note 6) was • Old Spire Warrants (with the exception of warrants for shares issued to European Investment Bank (“EIB,” and such warrants, the “EIB Warrants”) ) Pursuant to the Merger Agreement, at the Closing: • Each share of outstanding Class A common stock and Class B common stock of NavSight was exchanged for one share of Class A Common Stock of New Spire, par value per share (“New Spire Class A Common Stock”). • Each share of Old Spire Common Stock, including shares of Old Spire Common Stock issued pursuant to the conversion of the Old Spire Preferred Stock, the Convertible Notes and the Old Spire Warrants (excluding the EIB warrants), was converted into a number of shares of New Spire Class A Common Stock equal to the Per Share Closing Consideration (“the exchange ratio”) of as defined in the Merger Agreement. • Each share of Old Spire Common as defined in the Merger Agreement, payable in four equal tranches if the trading price of the New Spire Class A Common Stock is greater than or equal to following the Closing Date, as adjusted based on the formula defined in the Merger Agreement with respect to the portion of earnout value allocated to holders of options to purchase shares of Old Spire Common Stock (“Old Spire Options”) assumed by NavSight. • All outstanding Old Spire Options were assumed and converted into option awards that are exercisable for shares of New Spire Class A Common Stock pursuant to an o • The outstanding EIB Warrants were assumed by New Spire and converted into warrants that are exercisable for a number of shares of New Spire Class A Common Stock equal to the exchange ratio of • The Old Spire Founders purchased 12,058,61 4 All fractional shares were rounded down. On February 28, 2021, concurrently with the execution of the Merger Agreement, NavSight entered into Subscription Agreements with the PIPE Investors, pursuant to which the PIPE Investors collectively subscribed for shares of New Spire Class A Common Stock for an aggregate purchase price equal to (the “PIPE Investment”) less approximately of equity issuance costs associated with the PIPE Investment. The PIPE Investment was consummated immediately prior to the Closing. The number of shares of Common Stock issued immediately following the Closing was: Number of Shares Old Spire Common Stock (excluding Founders) 6,405,302 Old Spire Convertible Preferred Stock 42,873,636 Old Spire Convertible Notes 37,034,620 Old Spire Warrants (excluding EIB warrants) 672,355 Total Class A common shares to Old Spire stockholders (exclud ing 86,985,913 New Spire Class A Common Stock issued to Old Spire Founders 12,058,614 New Spire Class A Common Stock issued to PIPE Investors 24,500,000 New Spire Class A Common Stock held by public stockholders 1,979,515 New Spire Class A Common Stock issued to FP Lenders 2,468,492 New Spire Class A Common Stock resulting from conversion of NavSight Class B Common Stock 5,750,000 Total Shares of New Spire Class A Common Stock 133,742,534 New Spire Class B Common Stock issued to Old Spire Founders 12,058,614 Total Shares of New Spire Common Stock 145,801,148 The Merger is accounted for as a reverse recapitalization under GAAP. This determination is primarily based on Old Spire stockholders comprising a relative majority of the voting power of New Spire and having the ability to nominate the members of the board of directors of New Spire, Old Spire’s operations prior to the acquisition comprising the only ongoing operations of New Spire, and Old Spire’s senior management comprising a majority of the senior management of New Spire. Under this method of accounting, NavSight is treated as the “acquired” company for financial reporting purposes. Accordingly, for accounting purposes, the financial statements of Spire Global, Inc. represent a continuation of the financial statements of Old Spire with the Merger being treated as the equivalent of Old Spire issuing stock for the net assets of NavSight, accompanied by a recapitalization. The net assets of NavSight are stated at historical costs, with no goodwill or other intangible assets recorded. Operations prior to the Merger are presented as those of Old Spire. All periods prior to the Merger have been retrospectively adjusted using the exchange ratio for the equivalent number of shares outstanding immediately after the Merger to affect the reverse recapitalization. In connection with the Merger, the Company raised $264,823 of proceeds including the contribution of $230,027 of cash held in NavSight’s trust account from its initial public offering, net of redemptions of NavSight public stockholders of $210,204, and $245,000 of cash in connection with the PIPE Investment. The Company incurred of merger costs, consisting of banking, legal, and other professional fees, of which paid-in

Revenue, Contract Assets, Contr

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations	4. Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations Disaggregation of Revenue For the three an d l The following revenue disaggregated by geography was recognized: Three Months Ended Nine Months Ended EMEA (1) $ 3,514 37 % $ 13,426 47 % Americas (2) 4,805 50 % 10,561 37 % Asia Pacific (3) 1,242 13 % 4,403 16 % Total $ 9,561 100 % $ 28,390 100 % Three Months Ended Nine Months Ended EMEA (1) $ 2,909 41 % $ 10,149 48 % Americas (2) 2,823 39 % 8,038 38 % Asia Pacific (3) 1,452 20 % 3,034 14 % Total $ 7,184 100 % $ 21,221 100 % (1) The Netherlands represented 18% and 26% for the three and nine months ended September 30, 2021, respectively, and 25% and 36% for the three and nine months ended September 30, 2020, respectively. (2) U.S. represented 50% and 37% for the three and nine months ended September 30, 2021, respectively, and 39% and 38% for the three and nine months ended September 30, 2020, respectively. (3) Australia represented 11% for the nine months ended September 30, 2021, and 17% and 10% for the three and nine months ended September 30, 2020, respectively. Contract Assets At September 30, 2021 and December 31, 2020, Contract assets were Changes in Contract assets for the nine months ended September 30, 2021 were as follows: Balance at January 1, 2021 $ 853 Contract assets recorded 900 Reclassified to Accounts receivable (652 ) Other (12 ) Balance at September 30, 2021 $ 1,089 Contract Liabilities At September 30, 2021 and December 31, 2020, Contract liabilities were $10,331 and $8,110, respectively, and were reported in the current portion of Contract liabilities on the Company’s Condensed Consolidated Balance Sheets. Changes in Contract liabilities for the nine months ended September 30, 2021 and 2020 were as follows: September 30, September 30, Balance at the beginning of the year $ 8,110 $ 4,550 Contract liabilities recorded during the period 9,037 4,645 Revenue recognized during the period (6,624 ) (1,208 ) Other (192 ) — Balance at the end of the period $ 10,331 $ 7,987 Remaining Performance Obligations The Company has performance obligations associated with commitments in customer contracts for future services that have not yet been recognized as revenue. These commitments for future services exclude (i) contracts with an original term of one year or less, and (ii) cancellable contracts. As of September 30, 2021, the amount not yet recognized as revenue from these commitments is $49,506. The Company expects to recognize 70% of these future commitments over the next 12 months and the remaining 30% thereafter as revenue when the performance obligations are met.

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2021
Balance Sheet Components [Abstract]
Balance Sheet Components	5. Balance Sheet Components Other current assets consisted of the following: September 30, December 31, Prepaid insurance $ 6,083 $ 68 Technology and other prepaid contracts 1,687 767 Deferred contract costs 494 657 Prepaid rent 120 200 Other receivables 886 409 Other current assets 957 11 $ 10,227 $ 2,112 Property and equipment, net consisted of the following: September 30, December 31, Satellites in-service $ 32,076 $ 26,196 Internally developed software 2,166 2,166 Ground stations in-service 2,084 1,872 Leasehold improvements 1,589 1,589 Machinery and equipment 2,373 1,873 Computer equipment 1,485 1,153 Computer software and website development 472 472 Furniture and fixtures 458 379 42,703 35,700 Less: Accumulated depreciation and amortization (28,113 ) (23,260 ) 14,590 12,440 Satellite, launch and ground station work in progress 11,265 4,934 Finished satellites not in-service — 3,084 Property and equipment, net $ 25,855 $ 20,458 Other accrued expenses consisted of the following: September 30, December 31, Professional services $ 2,012 $ 420 Income taxes 709 105 Sales tax 26 122 Software 1,271 470 Satellite/launch/grounds material 829 — Other 1,120 696 $ 5,967 $ 1,813 Depreciation and amortization expense related to property and equipment for the three and nine months ended September 30, 2021 was $2,075 and $5,615, respectively, including amortization of internal-use internal-use

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Long-Term Debt	6. Long-Term Debt Long-term debt consisted of the following: September 30, December 31, Eastward Loan Facility $ — $ 15,000 EIB Loan Facility — 14,734 PPP Loan — 1,699 FP Term Loan 71,512 — Other — 10 71,512 31,443 Less: Debt issuance costs (26,291 ) (4,798 ) Non-current $ 45,221 $ 26,645 The Company recorded interest expense from long-term debt of $2,924 and $4,017 for the three and nine months ended September 30, 2021, respectively and $309 and $1,063 for the three and nine months ended September 30, 2020. FP Term Loan Facility The Company entered into a credit agreement with FP Credit Partners, L.P., as agent for several lenders (the “FP Lenders”) on April 15, 2021 and as amended on May 17, 2021 (the “FP Term Loan Agreement”), for a term loan (the “FP Term Loan”). Upon funding in May 2021, the FP Term Loan was used (i) to pay off the Company’s existing credit facilities with Eastward Fund Management, LLC (the “Eastward Loan Facility”) and EIB (the “EIB Loan Facility”) and (ii) to fund working capital and for general corporate purposes. The Company incurred of debt issuance costs relating to the FP Term Loan. As part of the transaction to extinguish the EIB Loan Facility, the Company has reserved in a restricted cash account in the event that EIB elects to redeem their warrants. Prior to the Closing, the FP Term Loan bore interest at a rate of per annum, payable quarterly in arrears, and the Company had the option to elect, upon written notice at least five business days in advance of each quarter end, to add all or a portion of the accrued unpaid interest to the outstanding principal amount of the FP Term Loan. Upon the Closing, this election was no longer available. The FP Lenders had the option to elect to convert a portion of their specified contractual return into common stock of the Company immediately preceding the Closing, at a conversion price specified in the FP Term Loan Agreement by submitting a notice to convert on or prior to the funding date in May 2021 (the “Conversion Election”). If the FP Lenders had exercised the Conversion Election, and the Company did not elect to repay the outstanding principal amount of the FP Term Loan at the Closing, then the interest rate would have increased to per annum. However, the FP Lenders did not make the Conversion Election and so the interest rate would have decreased to per annum upon the Closing under the original terms of the FP Term Loan Agreement. At the date of the FP Term Loan Agreement, this contingent interest feature was determined to be an embedded derivative asset with an associated debt premium recorded. The fair value of this financial instrument of $8,922 was presented net within Long-term Debt on the Condensed Consolidated Balance Sheet at June 30, 2021. However, because of this interest rate increase under the FP Amendment (as defined below), the contingent interest embedded derivative asset and associated debt premium were derecognized upon the execution of the FP Amendment . The FP Term Loan includes covenants that limit the Company’s ability to, among other things, make investments, dispose of assets, consummate mergers and acquisitions, incur additional indebtedness, grant liens, enter into transactions with affiliates, pay dividends or other distributions without preapproval by the FP Lenders. The Company is required to maintain minimum unrestricted cash of at least as of each fiscal quarter end, except for the quarter immediately following the first quarter where the Company reports positive EBITDA, until the closing of a qualifying IPO, which include s shares of New Spire Class A Common Stock with a value of to the FP Lenders upon funding of the FP Term Loan. On August 5, 2021, the Company and FP Lenders executed an amendment (the “FP Amendment”) to the FP Term Loan to modify certain terms. Among other things, the FP Amendment waived the instance of the noncompliance with provisions for the timely notification of the Company’s election to add accrued unpaid interest as of June 30, 2021 to the outstanding principal. The FP Lenders also waived any default interest that would have applied as a result of the noncompliance. The FP Amendment also reinstated the previously expired Conversion Election and served as formal notice of this election by the FP Lenders. As a result, the FP Lenders received shares of New Spire Class A Common Stock. In connection with FP’s exercise of the Conversion Election, the interest rate on the FP Term Loan increased to per annum following the closing of the Closing. The Company has determined that this FP Amendment represents an accounting modification of the original FP Term Loan. In connection with the debt modification accounting, no gain or loss was recorded related to the FP Amendment, and the Company capitalized the fair value of $14,803 for the shares of New Spire Class A Common Stock issued to the FP Lenders to be amortized over the remaining life of the FP Term Loan as part of the effective yield of the FP Term Loan beginning in the third quarter of 2021. The FP Term Loan, plus the applicable contractual returns as defined in the FP Term Loan Agreement, matures on April 15, 2026 and is collateralized by substantially all assets of the Company. The Company has the option to prepay the loan in advance of its final maturity, which was subject to a prepayment penalty under the original terms of the FP Term Loan Agreement that varied between On September 24, 2021, EIB submitted a notice of cancellation for 775,966 EIB warrants (Tranche A). The valuation for settlement of these warrants is based on a These warrants were settled subsequent to September 30, 2021 for EUR 9,670 D uring the nine months ended September 30, 2021, the Company recognized within Other income (expense), net on the Condensed Consolidate d Statement of Operations, as a loss on extinguishment of debt, resulting from paying off the EIB Loan Facility and the Eastward Loan Facility, and as a gain from extinguishment of debt resulting from the U.S. government’s forgiveness of the Company’s loan under the Paycheck Protection Program (“PPP”) established as part of the Coronavirus Aid, Relief, and Economic Security (“CARES”) Act.

Convertible Notes

Convertible Notes	9 Months Ended
	Sep. 30, 2021
Debt Instruments [Abstract]
Convertible Notes	7. Convertible Notes Between July 2019 and October 2020, the Company entered into several subordinated convertible note purchase agreements for gross proceeds totaling $42,884 (the “2019 and 2020 Convertible Notes”). The 2019 and 2020 Convertible Notes accrue interest at 8% per annum, compounded quarterly. In May 2021, the Company and the holders of the 2019 and 2020 Convertible Notes agreed to extend the maturity date of all convertible promissory notes outstanding at December 31, 2020 from January 29, 2022 to July 31, 2022. If not converted, at the option of the holders, all unpaid principal, interest and a balloon payment of 5% of the principal balance is due on the stated maturity date of July 31, 2022. The accretion of the carrying value of the Convertible Notes for the additional balloon payment is recorded as additional interest expense over the term of the 2019 and 2020 Convertible Notes. In connection with securing the 2019 and 2020 Convertible Notes, the Company incurred debt issuance costs of $392 that have been recorded as a deduction of the carrying amount of convertible debt and are being amortized to interest expense over the term of the 2019 and 2020 Convertible Notes. Conversion of the 2019 and 2020 Convertible Notes can be automatic based on events such as an initial public offering (“IPO”) by the Company or voluntary based on events such as a change of control or maturity. From January 2021 through February 2021, the Company issued and sold several convertible promissory notes in the aggregate amount of $20,000 (the “2021 Convertible Notes”, and together with the 2019 and 2020 Convertible Notes, the “Convertible Notes”). The 2021 Convertible Notes mature from the date of issuance and accrue interest at per annum, compounded quarterly. In connection with securing the 2021 Convertible Notes, the Company incurred debt issuance costs of that have been recorded as a deduction of the carrying amount of convertible debt and are being amortized to interest expense over the life of the 2021 Convertible Notes. Conversion of the 2021 Convertible Notes can be automatic based on events such as an IPO by the Company or voluntary based on events such as a change of control or maturity. Immediately prior to the effective time of the Merger, the Convertible Notes were automatically converted into shares of Old Spire Common Stock. The conversion ratio to Old Spire Common Stock for the 2019 and 2020 Convertible Notes was whereas the conversion ratio to Old Spire Common Stock for the 2021 Convertible Notes was This conversion then gave the right to receive shares of New Spire Class A Common Stock equal to the number of shares of Old Spire Common Stock received from such conversion multiplied exchange ratio of Total accrued interest on Convertible Notes was $0 and $5,944 as of September 30, 2021 and December 31, 2020, respectively, and included in Convertible notes payable, net on the Condensed Consolidated Balance Sheet. After the conversion of the Convertible Notes, the balloon interest accrual of $1,698 was reversed in August 2021, which was only payable upon full maturity of the Convertible Notes. The Company recorded a net interest expense reduction of $1,452 and $1,550 of interest expense on the Convertible Notes for the three and nine months ended September 30, 2021, respectively, and recorded

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurement	8. Fair Value Measurement The Company follows the guidance in ASC 820, “Fair Value Measurement” for its liabilities that are re-measured The fair value of the Company’s common and preferred stock warrant liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. The following fair value hierarchy is used to classify assets and liabilities based on the observable inputs and unobservable inputs used in order to value the assets and liabilities: Level 1: Quoted prices in active markets for identical assets or liabilities. An active market for an asset or liability is a market in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2: Observable inputs other than Level 1 inputs. Examples of Level 2 inputs include quoted prices in active markets for similar assets or liabilities and quoted prices for identical assets or liabilities in markets that are not active. Level 3: Unobservable inputs based on our assessment of the assumptions that market participants would use in pricing the asset or liability. The Company classifies financial instruments in Level 3 of the fair value hierarchy when there is reliance on at least one significant unobservable input to the valuation model. In addition to these unobservable inputs, the valuation models for Level 3 financial instruments typically also rely on a number of inputs that ar e The following tables present the Company’s fair value hierarchy for its financial instruments that are measured at fair value on a recurring basis: September 30, 2021 Level 1 Level 2 Level 3 Total Current Liabilities: EIB warrants $ — $ 22,582 $ — $ 22,582 Long-term Liabilities: Public warrants $ 19,550 $ — $ — $ 19,550 Private Placement warrants — 11,220 — 11,220 Contingent Earnout liability — — 77,130 77,130 $ 19,550 $ 11,220 $ 77,130 $ 107,900 December 31, 2020 Level 1 Level 2 Level 3 Total Long-term Liabilities: EIB warrants $ — $ — $ 4,007 $ 4,007 Public Warrants The fair value of the Public Warrants is based on quoted market process and is classified as a Level 1 financial instrument. Private Placement Warrants The fair value of the Private Warrants is estimated using the Black-Scholes model with inputs that include the Company’s stock price in an actively traded market, making this fair value classified as a Level 2 financial instrument. The other significant assumptions used in the model are the exercise price, expected term, volatility, interest rate, and dividend yield. The table below quantifies the significant inputs used for the Private Warrants: September 30, August 16, Fair value of the Company’s common stock $ 12.53 $ 9.93 Exercise price $ 11.50 $ 11.50 Risk-free interest rate 0.98 % 0.75 % Expected volatility factor 6.0 % 22.0 % Expected dividend yield — — Remaining contractual term (in years) 4.88 5.00 EIB Warrant Liabilities The warrant liability in the tables above consisted of the fair value of warrants to purchase the Company’s common stock at a price of $0.0001 per share (or redeem for cash) and preferred stock and was based on the significant inputs not observable in the market, which prior to the Merger represented a Level 3 measurement within the fair value hierarchy. The Company’s valuation of the stock warrants utilized the Black-Scholes option-pricing model, which incorporates assumptions and estimates to value the stock warrants. Changes in the fair value of the stock warrants are recognized in Other income (expense), net in the Condensed Consolidated Statements of Operations. The quantitative inputs utilized in the fair value measurement of the stock warrant liability include the fair value per share of the Company’s common stock, the remaining contractual term of the warrants, risk-free interest rate, expected dividend yield and expected volatility of the price of the Company’s common stock. Prior to the Merger, the Company determined the fair value per share of the Company’s common and preferred stock using a hybrid valuation method that utilized a combination of an option pricing model method and the Probability-Weighted Expected Return Method (“PWERM”). The PWERM is a scenario-based methodology that estimates the fair value of equity securities based upon an analysis of future values, assuming various outcomes. As the probability of the Merger closing increased, the fair value of the EIB warrant liability increased as of the date of the exercise. The risk-free interest rate is based on a treasury instrument for which the term is consistent with the expected life of the warrants. As there was no public market for the Company’s common and preferred stock, the Company determined the expected volatility for warrants granted based on an analysis of reported data for a peer group of companies. After the Merger, the EIB warrant liabilities moved from Level 3 to Level 2, as a result of the Company’s common stock now being traded on the New York Stock Exchange. The Company used a 20-day The table below quantifies the inputs used for the EIB warrants: September 30, December 31, Fair value of the Company’s common stock $ 14.55 $ 4.19 Exercise price $ 0.0001 $ 0.0001 Risk-free interest rate 0.98 % 0.13 % Expected volatility factor 70.0 % 68.4 % Expected dividend yield — — Remaining contractual term (in years) 3.9 4.7 Contingent Earnout Liability The estimated fair value of the contingent earnout liability was determined using a Monte Carlo simulation using a distribution of potential outcomes on a monthly basis over the Earnout Period (Note 3) prioritizing the most reliable information available. The assumptions utilized in the calculation are based on the achievement of certain stock price milestones, including the current price of the Company’s common stock, expected volatility, risk-free rate, expected term and dividend rate. The table below quantifies the significant inputs used for the Contingent Earnout Liability: September 30, August 16, Fair value of the Company’s common stock $ 12.53 $ 9.93 Risk-free interest rate 0.98 % 0.75 % Expected volatility factor 70.0 % 70.0 % Expected dividend yield — — Remaining contractual term (in years) 0.004 0.004 The following tables present the Company’s fair value hierarchy for its warrants classified as equity that are measured at fair value on a nonrecurring basis: September 30, 2021 Level 1 Level 2 Level 3 Total Equity: Warrants $ — $ — $ 970 $ 970 December 31, 2020 Level 1 Level 2 Level 3 Total Equity: Warrants $ — $ — $ 970 $ 970 The warrant liability in the table above classified as equity was recorded at fair value on the date of issuance and is not remeasured. The fair value of warrants was based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The Company’s valuation of the stock warrants utilized the Black-Scholes option-pricing model, which incorporates assumptions and estimates to value the stock warrants. The following table presents a summary of the changes in the fair value of the Company’s Level 3 financial instruments that are measured at fair value on a recurring basis: Contingent Contingent Warrant Fair value at December 31, 2019 $ — $ — $ 197 Issuance of warrants to EIB — — 1,806 Fair value at September 30, 2020 $ — $ — $ 2,003 Fair value at December 31, 2020 $ — $ — $ 4,007 Issuance of warrants to Silicon Valley Bank — — 308 Conversion of Silicon Valley Bank warrants to common stock — — (308 ) Exercise of series C preferred warrants — — (891 ) Contingent interest embedded derivative recognized relating to the FP Term Loan agreement — 8,922 — Contingent interest embedded derivative derecognized upon the execution of the FP Amendment — (8,922 ) — Contingent earnout liability recognized upon the closing of the reverse recapitalization 77,170 — — Change in fair value included in other income (expense), net(1) — — 19,466 Transferred to Level 2 upon the closing of the reverse recapitalization — — (22,582 ) Fair value at September 30, 2021 $ 77,170 $ — $ — (1) Included in the Change in fair value recorded in other income (expense), net was $9,290 and $0 for the three months ended September 30, 2021 and 202 0 During the nine months ended September 30, 2021, the Company issued warrants at a fair value of $308 to Silicon Valley Bank with an exercise price of The warrants allow the holder to acquire the Company’s common stock. Silicon Valley Bank exercised the Series C warrants and they were converted into common stock upon the Closing. Certain holders of Series C preferred stock exercised their warrants at a nominal amount to purchase shares of the Company’s common stock at a fair value of $891 during the nine months ended September 30, 2021. Based on the recent rounds of debt financing during the nine months ended September 30, 2021 and the year ended December 31, 2020 and the terms of those debt agreements, current market conditions and the Company’s financial condition, the carrying amounts for Long-term debt and Convertible notes payable approximate fair value. The carrying amounts reported on the Condensed Consolidated Balance Sheets of other assets and liabilities which are considered to be financial instruments approximate fair value based on their short-term nature and current market indicators and are classified as Level 3.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. Commitments and Contingencies Operating Leases The Company leases office facilities and sites for its ground stations under noncancelable operating leases. These leases expire at various dates through 2029. Rent expense, including ground station leases, for the three and nine months ended September 30, 202 1 0 Future minimum lease payments under noncancelable operating leases that have initial or remaining noncancelable lease terms greater than one-year s Remainder of 2021 $ 583 2022 2,372 2023 2,353 2024 2,231 2025 2,202 2026 and thereafter 5,062 $ 14,803 Litigation At times, the Company is party to various claims and legal actions arising in the normal course of busi n

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	10. Stock-Based Compensation In December 2012, the Company adopted the 2012 Stock Option and Grant Plan (the “Plan”) under which the Company may grant stock options to purchase shares of its common stock to certain employees and nonemployees of the Company. The 2012 Plan was terminated as of the Closing, and accordingly, no additional awards will be granted under the 2012 Plan thereafter. In connection with the Closing, the Company adopted the 2021 Equity Incentive Plan (the “2021 Plan”) and the 2021 Employee Stock Purchase Plan (“2021 ESPP”). The number of shares available for issuance under the 2021 Plan will be increased on the first day of each fiscal year, beginning on January 1, 2022, in an amount equal to the lesser of (i) shares of New Spire Class A Common Stock, (ii) a number of shares of New Spire Class A Common Stock equal to of the total number of shares of all of New Spire Class A Common Stock outstanding as of the last day of the immediately preceding fiscal year, or (iii) such number of shares of New Spire Class A Common Stock as the Company’s board of directors or its designated committee may determine no later than the last day of the immediately preceding fiscal year. The 2021 Plan permits the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock, restricted stock units, and performance awards to employees, directors, or consultants under the 2021 Plan. The 2021 ESPP, the Company can grant stock options to employees to purchase shares of Class A common stock at a purchase price which equals to 85% of the lower of (i) the fair market value of common stock on the first trading day of the offering period or (ii) the fair market value of common stock on the exercise date. As of September 30, 2021, 8,869,629 and 3,194,000 shares were available for grant under the 2021 Plan and 2021 ESPP, respectively. The following table summarizes stock option activity under the Plan, there were no activities under the 2021 Plan for the period ending September 30, 2021: Number of Weighted- Weighted- Stock options 19,618,953 $ 1.78 7.9 Granted 4,676,898 4.90 Exercised (799,901 ) 1.33 Forfeited, canceled, or expired (1,325,349 ) 2.50 Stock options 22,170,601 2.42 7.5 Vested and expected to vest at September 30, 2021 22,170,601 2.42 7.5 Exercisable at September 30, 2021 10,895,186 1.81 6.1 The Company’s option award quantities and prices prior to the Merger have been retroactively restated to reflect the exchange ratio of approximately established in the Merger as described in Note 3. The weighted-average grant date fair value per share of stock options granted was $2.94 for the nine months ended September 30, 2021. The total grant date fair value of stock options vested was $ 1,737 As of September 30, 2021, there was $17,903 of total unrecognized compensation expense expected to be recognized over a weighted average-period of 2.93 years. The following table summarizes the components of total stock-based compensation expense based on roles and responsibilities of the employees within the Condensed Consolidated Statements of Operations: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Cost of revenue $ 31 $ 9 $ 75 $ 26 Research and development 590 225 1,843 668 Sales and marketing 550 74 1,278 219 General and administrative 928 223 3,404 538 $ 2,099 $ 531 $ 6,600 $ 1,451

Net Loss per Share

Net Loss per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Net Loss per Share	11. Net Loss per Share The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Numerator: Net loss attributable to common stockholders $ (32,701 ) $ (7,624 ) $ (79,261 ) $ (22,340 ) Denominator: Weighted-average shares of New Spire Class A Common Stock used in computing basic and diluted net loss per share 67,348,269 17,605,469 37,389,424 17,603,874 Basic and diluted net loss per share (New Spire Class A Common Stock) $ (0.49 ) $ (0.43 ) $ (2.12 ) $ (1.27 ) The Company has two types of common stock, Class A and Class B. Class B common stock has no economic rights, therefore has been excluded from the computation of basic and diluted net loss per share. The Company’s potential dilutive securities have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the nine months ended September 30, because including them would have had an anti-dilutive effect: September 30, 2021 2020 Convertible preferred stock (if-converted) — 42,726,773 Warrants for the purchase of Series C convertible preferred stock (if-converted) — 146,919 Warrants for the purchase of common stock — 1,285,078 Convertible notes (if-converted) — 34,670,225 Stock options to purchase common stock 22,170,601 13,778,549 22,170,601 92,607,544

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	12. Subsequent Events The Company has evaluated subsequent events and has determined that no adjustments or additional disclosures are necessary to the amounts reported in the accompanying Unaudited Condensed Consolidated Financial Statements, except as disclosed below: Redemption of EIB Warrants On October 18, 2021, EIB submitted a notice of cancellation for the remaining 775,966 EIB warrants (Tranche B). The valuation for settlement of these warrants is based on the VWAP 20-day The settlement amount is EUR Tranche A of the EIB Warrants, in respect of which EIB submitted a notice of cancellation on September 24, 2021 (Note 6), and Tranche B of the EIB Warrants were canceled in full in exchange for a total cash amount of EUR , which was paid to EIB on November 8, 2021. Upon settlement of the warrants, the cash collateral of $ will cease to be restricted.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The condensed consolidated financial statements and accompanying notes are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and regulations of the U.S. Securities and Exchange Commission for interim financial reporting. The condensed consolidated financial statements for the three and nine months ended September 30, 2021 include the accounts of Spire Global, Inc. (i.e. former NavSight) and its wholly-owned subsidiary, Old Spire, following the Reverse Recapitalization as further discussed in Note 3 “Reverse Recapitalization.” For periods prior to the Merger, the reported share and per share amounts have been retroactively converted by applying the Exchange Ratio with the exception of authorized shares. Issued and outstanding shares and warrants as disclosed herein have been adjusted reflecting the Exchange Ratio. All other accompanying financial statements as of December 31, 2020 and for the three and nine months ended September 30, 2020 include only the accounts of Old Spire. Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the related notes for the years ended December 31, 2020 and 2019. The information as of December 31, 2020 included on the condensed consolidated balance sheets was derived from the Company’s audited consolidated financial statements. The unaudited condensed consolidated financial statements were prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, contain all adjustments, consisting of normal recurring adjustments necessary for a fair statement of its financial position, results of operations and cash flows for the periods indicated. All intercompany accounts and transactions have been eliminated in consolidation. Operating results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for any other interim period or for the year ending December 31, 2021.
Liquidity Risks and Uncertainties	Liquidity Risks and Uncertainties The unaudited condensed consolidated financial statements have been prepared on the basis of continuity of operations, the realization of assets, and the satisfaction of liabilities in the ordinary course of business. Since inception, the Company has been engaged in developing its product offerings, raising capital, and recruiting personnel. The Company’s operating plan may change as a result of many factors currently unknown and there can be no assurance that the current operating plan will be achieved in the time frame anticipated by the Company, and it may need to seek additional funds sooner than planned. If adequate funds are not available to the Company on a timely basis, it may be required to delay, limit, reduce, or terminate certain commercial efforts, or pursue merger or acquisition strategies, all of which could adversely affect the holdings or the rights of the Company’s stockholders. The Company has a history of operating losses and negative cash flows from operations since inception. During the nine months ended September 30, 2021, net loss was $79,261 and cash used in operations was $40,008. During the nine months ended September 30, 2020, net loss was $22,340 and cash used in operations was $8,420. The Company held cash and cash equivalents of $245,770, excluding restricted cash, at September 30, 2021. On August 16, 2021, the Company received net proceeds of approximately $236,632 from Private Investment in Public Equity (“PIPE”) The Company’s assessment of the period of time through which its financial resources will be adequate to support its operations is a forward-looking statement and involves risks and uncertainties. The Company’s actual results could vary as a result of many factors, including its growth rate, subscription renewal activity, the timing and extent of spending to support its infrastructure and research and development efforts and the expansion of sales and marketing activities. The Company may in the future enter into arrangements to acquire or invest in complementary businesses, services, and technologies, including intellectual property rights. The Company has based its estimates on assumptions that may prove to be wrong, and it could use its available capital resources sooner than it currently expects. The Company may be required to seek additional equity or debt financing. Future liquidity and cash requirements will depend on numerous factors, including market penetration, the introduction of new products, and potential acquisitions of related businesses or technology. In the event that additional financing is required from outside sources, the Company may not be able to raise it on acceptable terms or at all. If the Company is unable to raise additional capital when desired, or if it cannot expand its operations or otherwise capitalize on its business opportunities because it lacks sufficient capital, its business, operating results, and financial condition would be adversely affected.
COVID-19 Impact	COVID-19 In March 2020, the World Health Organization declared the outbreak of COVID-19 shelter-in-place COVID-19 day-to-day COVID-19 COVID-19 COVID-19 COVID-19 re-work COVID-19
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the dates of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. Management’s significant estimates include assumptions in revenue recognition, contingent earnout liability, allowance for doubtful accounts, realizability of deferred income tax assets, equity awards and warrant liabilities. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment. The Company adjusts such estimates and assumptions based on the facts and circumstances. As future events and their effects cannot be determined with precision, actual results could differ from those estimates.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Restricted cash, current and restricted cash included in Other long-term assets in the Condensed Consolidated Balance Sheets represents amounts pledged as guarantees or collateral for financing arrangements (Note 6 and Note 12) and lease agreements, as contractually required. The following table shows components of cash, cash equivalents, and restricted cash reported on the Condensed Consolidated Balance Sheets and in the Condensed Consolidated Statements of Cash Flows as of: September 30, December 31, Cash and cash equivalents $ 245,770 $ 15,571 Restricted cash, current 12,801 — Restricted cash included in Other long-term assets 396 415 $ 258,967 $ 15,986
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash, cash equivalents and restricted cash, and accounts receivable. The Company typically has cash account balances in excess of Federal Deposit Insurance Corporation insurance coverage. The Company has not experienced any losses on such accounts, and management believes that the Company’s risk of loss is remote. The Company has a concentration of contractual revenue arrangements with governmental agencies and nongovernmental entities. Entities under common control are reported as a single customer. As of September 30, 2021, the Company had three customers that accounted for 21%, 19% and 12% of the Company’s total account receivable and as of December 31, 2020, the Company had one customer that accounted for 67% of the Company’s total accounts receivable. The Company had the following customers whose revenue balances individually represented 10% or more of the Company’s total revenue: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Customer A 18 % 24 % 27 % 35 % Customer B 17 % 20 % 19 % 21 % Customer C * 16 % 11 % 10 % * Revenue from these customers were less than 10% of total revenue during the period.
Deferred Offering and Merger Costs	Deferred Offering and Merger Costs The Company capitalizes within Other current assets on the Condensed Consolidated Balance Sheets certain legal, accounting and other third-party fees that are directly related to the Company’s in-process of such costs as of September 30, 2021. As of the Closing, these capitalized merger costs were recorded to Additional paid-in capital on the Condensed Consolidated Balance Sheet (Note 3). During the nine months ended September 30, 2021, the Company incurred an additional $6,591 of costs indirectly related to the Merger, including of other merger related costs. These amounts have been included in General and administrative expenses in the Condensed Consolidated Statements of Operations for the nine months ended September 30, 2021. No such costs were incurred during the nine months ended September 30, 2020.
Related Parties	Related Parties One of the Company’s stockholders and debtors is also a customer from which the Company generated $606 of revenue for the nine months ended September 30, 2020. No revenue was generated from this customer for the nine months ended September 30, 2021. The Company borrowed gross proceeds of $1,232 of Convertible notes payable in February 2021 and $6,414 of Convertible notes payable during the year ended December 31, 2019, from certain stockholders (Note 7). Interest expense recognized on related party Convertible notes payable was $89 and $413 for the three and nine months ended September 30, 2021, respectively, and Immediately prior to the effective time of the Merger, the Convertible Notes were automatically converted into shares of common stock of Old Spire (“Old Spire Common Stock”) (Note 3 and Note 7). Total carrying value of the related party balance included as Convertible notes payable, net on the Condensed Consolidated Balance Sheets was
Common Stock Warrants	Common Stock Warrants The Company assumed 11,499,992 c 0.0001 11.50 non-redeemable The Company evaluated the Common Stock Warrants and concluded that they do not meet the criteria to be classified within stockholders’ equity. The agreement governing the Common Stock Warrants includes a provision that could result in a different settlement value for the Common Stock Warrants depending on their holder. Because the holder of an instrument is not an input into the pricing of a fixed-for-fixed 50
Contingent Earnout Liability	Contingent Earnout Liability In connection with the Reverse Recapitalization and pursuant to the Merger Agreement, eligible Spire equity holders are entitled to receive additional shares of the Company’s Common Stock upon the Company achieving certain Earnout Triggering Events (as described in the Merger Agreement and Note 3). In accordance with ASC 815-40, The contingent earnout liability is categorized as a Level 3 fair value measurement using the Monte Carlo model (Note 8) because the Company estimates projections during the Earnout Period utilizing unobservable inputs. Contingent earnout payments involve certain assumptions requiring significant judgment and actual results may differ from assumed and estimated amounts.
Accounting Pronouncements Recently Adopted	Accounting Pronouncements Recently Adopted In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-13, Financial Instruments—Credit Losses (Topic 326) Measurement of Credit Losses on Financial Instruments 2016-13 2016-13 In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal Use Software (Subtopic 350-40): 2018-15 In March 2020 and January 2021, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting 2021-01, Reference Rate Reform (Topic 848) 2020-04 2021-01
Accounting Pronouncements Not Yet Adopted	Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) right-of-use In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes non-income-based In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805), Accounting for Contract Assets and Contract Liabilities from Contracts with Customers

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of cash, cash equivalents, and restricted cash	The following table shows components of cash, cash equivalents, and restricted cash reported on the Condensed Consolidated Balance Sheets and in the Condensed Consolidated Statements of Cash Flows as of: September 30, December 31, Cash and cash equivalents $ 245,770 $ 15,571 Restricted cash, current 12,801 — Restricted cash included in Other long-term assets 396 415 $ 258,967 $ 15,986
Summary of customers whose revenue and accounts receivable balances	The Company had the following customers whose revenue balances individually represented 10% or more of the Company’s total revenue: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Customer A 18 % 24 % 27 % 35 % Customer B 17 % 20 % 19 % 21 % Customer C * 16 % 11 % 10 % * Revenue from these customers were less than 10% of total revenue during the period.

Reverse Recapitalization (Table

Reverse Recapitalization (Tables)	9 Months Ended
	Sep. 30, 2021
Business Combinations [Abstract]
Summary of Number of Shares of Common Stock Issued	The number of shares of Common Stock issued immediately following the Closing was: Number of Shares Old Spire Common Stock (excluding Founders) 6,405,302 Old Spire Convertible Preferred Stock 42,873,636 Old Spire Convertible Notes 37,034,620 Old Spire Warrants (excluding EIB warrants) 672,355 Total Class A common shares to Old Spire stockholders (exclud ing 86,985,913 New Spire Class A Common Stock issued to Old Spire Founders 12,058,614 New Spire Class A Common Stock issued to PIPE Investors 24,500,000 New Spire Class A Common Stock held by public stockholders 1,979,515 New Spire Class A Common Stock issued to FP Lenders 2,468,492 New Spire Class A Common Stock resulting from conversion of NavSight Class B Common Stock 5,750,000 Total Shares of New Spire Class A Common Stock 133,742,534 New Spire Class B Common Stock issued to Old Spire Founders 12,058,614 Total Shares of New Spire Common Stock 145,801,148

Revenue, Contract Assets, Con_2

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue by Geography	The following revenue disaggregated by geography was recognized: Three Months Ended Nine Months Ended EMEA (1) $ 3,514 37 % $ 13,426 47 % Americas (2) 4,805 50 % 10,561 37 % Asia Pacific (3) 1,242 13 % 4,403 16 % Total $ 9,561 100 % $ 28,390 100 % Three Months Ended Nine Months Ended EMEA (1) $ 2,909 41 % $ 10,149 48 % Americas (2) 2,823 39 % 8,038 38 % Asia Pacific (3) 1,452 20 % 3,034 14 % Total $ 7,184 100 % $ 21,221 100 % (1) The Netherlands represented 18% and 26% for the three and nine months ended September 30, 2021, respectively, and 25% and 36% for the three and nine months ended September 30, 2020, respectively. (2) U.S. represented 50% and 37% for the three and nine months ended September 30, 2021, respectively, and 39% and 38% for the three and nine months ended September 30, 2020, respectively. (3) Australia represented 11% for the nine months ended September 30, 2021, and 17% and 10% for the three and nine months ended September 30, 2020, respectively.
Schedule of Changes in Contract Assets	Changes in Contract assets for the nine months ended September 30, 2021 were as follows: Balance at January 1, 2021 $ 853 Contract assets recorded 900 Reclassified to Accounts receivable (652 ) Other (12 ) Balance at September 30, 2021 $ 1,089
Schedule of Changes in Contract Liabilities	Changes in Contract liabilities for the nine months ended September 30, 2021 and 2020 were as follows: September 30, September 30, Balance at the beginning of the year $ 8,110 $ 4,550 Contract liabilities recorded during the period 9,037 4,645 Revenue recognized during the period (6,624 ) (1,208 ) Other (192 ) — Balance at the end of the period $ 10,331 $ 7,987

Balance Sheet Components (Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2021
Balance Sheet Components [Abstract]
Schedule of Other Current Assets	Other current assets consisted of the following: September 30, December 31, Prepaid insurance $ 6,083 $ 68 Technology and other prepaid contracts 1,687 767 Deferred contract costs 494 657 Prepaid rent 120 200 Other receivables 886 409 Other current assets 957 11 $ 10,227 $ 2,112
Summary of Property Plant and Equipment,Net	Property and equipment, net consisted of the following: September 30, December 31, Satellites in-service $ 32,076 $ 26,196 Internally developed software 2,166 2,166 Ground stations in-service 2,084 1,872 Leasehold improvements 1,589 1,589 Machinery and equipment 2,373 1,873 Computer equipment 1,485 1,153 Computer software and website development 472 472 Furniture and fixtures 458 379 42,703 35,700 Less: Accumulated depreciation and amortization (28,113 ) (23,260 ) 14,590 12,440 Satellite, launch and ground station work in progress 11,265 4,934 Finished satellites not in-service — 3,084 Property and equipment, net $ 25,855 $ 20,458
Schedule of Other Accrued expenses	Other accrued expenses consisted of the following: September 30, December 31, Professional services $ 2,012 $ 420 Income taxes 709 105 Sales tax 26 122 Software 1,271 470 Satellite/launch/grounds material 829 — Other 1,120 696 $ 5,967 $ 1,813

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Summary of Long-term Debt	Long-term debt consisted of the following: September 30, December 31, Eastward Loan Facility $ — $ 15,000 EIB Loan Facility — 14,734 PPP Loan — 1,699 FP Term Loan 71,512 — Other — 10 71,512 31,443 Less: Debt issuance costs (26,291 ) (4,798 ) Non-current $ 45,221 $ 26,645

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present the Company’s fair value hierarchy for its financial instruments that are measured at fair value on a recurring basis: September 30, 2021 Level 1 Level 2 Level 3 Total Current Liabilities: EIB warrants $ — $ 22,582 $ — $ 22,582 Long-term Liabilities: Public warrants $ 19,550 $ — $ — $ 19,550 Private Placement warrants — 11,220 — 11,220 Contingent Earnout liability — — 77,130 77,130 $ 19,550 $ 11,220 $ 77,130 $ 107,900 December 31, 2020 Level 1 Level 2 Level 3 Total Long-term Liabilities: EIB warrants $ — $ — $ 4,007 $ 4,007
Summary of Warrants Classified as Equity That Are Measured at Fair Value on Nonrecurring Basis	The following tables present the Company’s fair value hierarchy for its warrants classified as equity that are measured at fair value on a nonrecurring basis: September 30, 2021 Level 1 Level 2 Level 3 Total Equity: Warrants $ — $ — $ 970 $ 970 December 31, 2020 Level 1 Level 2 Level 3 Total Equity: Warrants $ — $ — $ 970 $ 970
Summary of Change in Fair Value of The Warrant Liabilities	The following table presents a summary of the changes in the fair value of the Company’s Level 3 financial instruments that are measured at fair value on a recurring basis: Contingent Contingent Warrant Fair value at December 31, 2019 $ — $ — $ 197 Issuance of warrants to EIB — — 1,806 Fair value at September 30, 2020 $ — $ — $ 2,003 Fair value at December 31, 2020 $ — $ — $ 4,007 Issuance of warrants to Silicon Valley Bank — — 308 Conversion of Silicon Valley Bank warrants to common stock — — (308 ) Exercise of series C preferred warrants — — (891 ) Contingent interest embedded derivative recognized relating to the FP Term Loan agreement — 8,922 — Contingent interest embedded derivative derecognized upon the execution of the FP Amendment — (8,922 ) — Contingent earnout liability recognized upon the closing of the reverse recapitalization 77,170 — — Change in fair value included in other income (expense), net(1) — — 19,466 Transferred to Level 2 upon the closing of the reverse recapitalization — — (22,582 ) Fair value at September 30, 2021 $ 77,170 $ — $ — (1) Included in the Change in fair value recorded in other income (expense), net was $9,290 and $0 for the three months ended September 30, 2021 and 202 0
Private Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Quantitative Information Regarding Warrant Liability	The table below quantifies the significant inputs used for the Private Warrants: September 30, August 16, Fair value of the Company’s common stock $ 12.53 $ 9.93 Exercise price $ 11.50 $ 11.50 Risk-free interest rate 0.98 % 0.75 % Expected volatility factor 6.0 % 22.0 % Expected dividend yield — — Remaining contractual term (in years) 4.88 5.00
E I B warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Quantitative Information Regarding Warrant Liability	The table below quantifies the inputs used for the EIB warrants: September 30, December 31, Fair value of the Company’s common stock $ 14.55 $ 4.19 Exercise price $ 0.0001 $ 0.0001 Risk-free interest rate 0.98 % 0.13 % Expected volatility factor 70.0 % 68.4 % Expected dividend yield — — Remaining contractual term (in years) 3.9 4.7
Contingent Earnoutliability Member [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Quantitative Information Regarding Warrant Liability	The table below quantifies the significant inputs used for the Contingent Earnout Liability: September 30, August 16, Fair value of the Company’s common stock $ 12.53 $ 9.93 Risk-free interest rate 0.98 % 0.75 % Expected volatility factor 70.0 % 70.0 % Expected dividend yield — — Remaining contractual term (in years) 0.004 0.004

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments For Noncancelable Operating Leases	Future minimum lease payments under noncancelable operating leases that have initial or remaining noncancelable lease terms greater than one-year s Remainder of 2021 $ 583 2022 2,372 2023 2,353 2024 2,231 2025 2,202 2026 and thereafter 5,062 $ 14,803

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Stock Option Activity	The following table summarizes stock option activity under the Plan, there were no activities under the 2021 Plan for the period ending September 30, 2021: Number of Weighted- Weighted- Stock options 19,618,953 $ 1.78 7.9 Granted 4,676,898 4.90 Exercised (799,901 ) 1.33 Forfeited, canceled, or expired (1,325,349 ) 2.50 Stock options 22,170,601 2.42 7.5 Vested and expected to vest at September 30, 2021 22,170,601 2.42 7.5 Exercisable at September 30, 2021 10,895,186 1.81 6.1
Summary of the Stock Based Compensation Expense based on Roles and Responsibilities of the Employees	The following table summarizes the components of total stock-based compensation expense based on roles and responsibilities of the employees within the Condensed Consolidated Statements of Operations: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Cost of revenue $ 31 $ 9 $ 75 $ 26 Research and development 590 225 1,843 668 Sales and marketing 550 74 1,278 219 General and administrative 928 223 3,404 538 $ 2,099 $ 531 $ 6,600 $ 1,451

Net Loss per Share (Tables)

Net Loss per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Earnings Per Share Basic and Diluted Attributable to Common Stockholders	The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Numerator: Net loss attributable to common stockholders $ (32,701 ) $ (7,624 ) $ (79,261 ) $ (22,340 ) Denominator: Weighted-average shares of New Spire Class A Common Stock used in computing basic and diluted net loss per share 67,348,269 17,605,469 37,389,424 17,603,874 Basic and diluted net loss per share (New Spire Class A Common Stock) $ (0.49 ) $ (0.43 ) $ (2.12 ) $ (1.27 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the nine months ended September 30, because including them would have had an anti-dilutive effect: September 30, 2021 2020 Convertible preferred stock (if-converted) — 42,726,773 Warrants for the purchase of Series C convertible preferred stock (if-converted) — 146,919 Warrants for the purchase of common stock — 1,285,078 Convertible notes (if-converted) — 34,670,225 Stock options to purchase common stock 22,170,601 13,778,549 22,170,601 92,607,544

Nature of Business - Additional

Nature of Business - Additional Information (Detail) - Exact Earth Acquisition [Member] $ in Millions	Sep. 13, 2021USD ($)shares
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Total consideration	$ 161.2
Business acquisition, consideration paid in cash	103.4
Business acquisition, consideration issued or issuable of equity	$ 57.8
Business acquisition, consideration issued or issuable of equity, shares | shares	5,234,857
Percentage of rights had not been exercised	10.00%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Summary of Cash, Cash Equivalents, and Restricted Cash (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 245,770	$ 15,571
Restricted cash, current	12,801	0
Restricted cash included in Other long-term assets	396	415
Cash, cash equivalents, restricted cash and restricted cash equivalents	$ 258,967	$ 15,986	$ 11,205	$ 24,531

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Customers Whose Revenue and Accounts Receivable Balances (Detail) - Customer Concentration Risk [Member] - Revenue [Member]	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Customer A
Concentration Risk [Line Items]
Concentration Customer Risk, Percentage	18.00%	24.00%	27.00%	35.00%
Customer B
Concentration Risk [Line Items]
Concentration Customer Risk, Percentage	17.00%	20.00%	19.00%	21.00%
Customer C
Concentration Risk [Line Items]
Concentration Customer Risk, Percentage		16.00%	11.00%	10.00%

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Summary of Customers Whose Revenue and Accounts Receivable Balances (Parenthetical) (Detail) - Customer Concentration Risk [Member] - Revenue [Member]	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Concentration Risk [Line Items]
Concentration risk percentage	100.00%	100.00%	100.00%	100.00%
Maximum [Member]
Concentration Risk [Line Items]
Concentration risk percentage	10.00%

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 16, 2021	Feb. 28, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Line Items]
Net loss			$ (32,701)	$ (7,624)	$ (79,261)	$ (22,340)
Net Cash used in operating activities					40,008	8,420
Cash and cash equivalents at carrying value			245,770		245,770
Capitalized merger related costs			3,871		3,871		$ 0
Related party transaction, Notes payable non current			$ 0		$ 0		7,498
Net proceeds from merger transaction	$ 236,632
Common Stock, Par or Stated Value Per Share			$ 0.0001		$ 0.0001
Class of Warrant or Right, Exercise Price of Warrants or Rights			$ 11.50		$ 11.50
Public Warrants [Member]
Accounting Policies [Line Items]
Class of warrants or right issued during the period					11,499,992
Private Placement Warrants [Member]
Accounting Policies [Line Items]
Class of warrants or right issued during the period					6,600,000
One Of The Stockholders And Debtors WhoIs Also A Customer [Member]
Accounting Policies [Line Items]
Revenue from related party					$ 0	606
Stockholder [Member]
Accounting Policies [Line Items]
Related party transaction, Notes payable non current			$ 0		0		$ 7,498
Stockholder [Member] | Borrowed Convertible Notes Payable [Member] | Convertible Debt [Member]
Accounting Policies [Line Items]
Proceeds from related party debt		$ 1,232						$ 6,414
Related party transaction, Interest expenses			$ 89	$ 139	413	405
General and Administrative Expense [Member]
Accounting Policies [Line Items]
Non cash merger related costs					6,591	$ 0
Professional fees					4,846
Other merger related costs					$ 1,745
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Accounting Policies [Line Items]
Concentration risk percentage							67.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer A [Member]
Accounting Policies [Line Items]
Concentration risk percentage					21.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer B [Member]
Accounting Policies [Line Items]
Concentration risk percentage					19.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer C [Member]
Accounting Policies [Line Items]
Concentration risk percentage					12.00%
Maximum [Member]
Accounting Policies [Line Items]
Investments, Maturity terms					3 months

Reverse Recapitalization - Summ

Reverse Recapitalization - Summary of Number of Shares of Common Stock Issued (Detail)	Sep. 30, 2021shares
Old Spire Common Stock (excluding Founders)
Class of Stock [Line Items]
Common stock, Issued	6,405,302
Old Spire Convertible Preferred Stock
Class of Stock [Line Items]
Common stock, Issued	42,873,636
Old Spire Convertible Notes
Class of Stock [Line Items]
Common stock, Issued	37,034,620
Old Spire Warrants (excluding EIB warrants)
Class of Stock [Line Items]
Common stock, Issued	672,355
Total Class A common shares to Old Spire stockholders (excluding Founders)
Class of Stock [Line Items]
Common stock, Issued	86,985,913
New Spire Class A Common Stock issued to Old Spire Founders
Class of Stock [Line Items]
Common stock, Issued	12,058,614
New Spire Class A Common Stock issued to PIPE Investors
Class of Stock [Line Items]
Common stock, Issued	24,500,000
New Spire Class A Common Stock held by public stockholders
Class of Stock [Line Items]
Common stock, Issued	1,979,515
New Spire Class A Common Stock issued to FP Lenders
Class of Stock [Line Items]
Common stock, Issued	2,468,492
New Spire Class A Common Stock resulting from conversion of NavSight Class B Common Stock
Class of Stock [Line Items]
Common stock, Issued	5,750,000
Total Shares of New Spire Class A Common Stock
Class of Stock [Line Items]
Common stock, Issued	133,742,534
New Spire Class B Common Stock issued to Old Spire Founders
Class of Stock [Line Items]
Common stock, Issued	12,058,614
Total Shares of New Spire Common Stock
Class of Stock [Line Items]
Common stock, Issued	145,801,148

Reverse Recapitalization - Addi

Reverse Recapitalization - Additional Information (Detail) $ / shares in Units, $ in Thousands	Aug. 16, 2021shares	Aug. 31, 2021USD ($)$ / sharesshares	Sep. 30, 2021USD ($)$ / shares	Sep. 30, 2020USD ($)
Common stock per share | $ / shares			$ 0.0001
Proceeds from issuance initial public offering		$ 264,823
Cash held in trust account		230,027
Proceeds from issuance or sale of equity		210,204
Proceeds from issuance of financial Services obligations		245,000
Payments of merger related costs		38,653
Payments of financing costs			$ 4,293	$ 183
Additional Paid In Capital [Member]
Payments of financing costs		32,062
Selling, General and Administrative Expenses [Member]
Payments of financing costs		$ 6,591
Old Spire Options [Member]
Exchange ratio of common stock		1.8282
Number of consecutive trading days for determining share price		20 days
Number of trading days for determining share price		30 days
Closing date of warrants		5 years
Class of warrants and rights exchange ratio		1.7058
First Tranches Share Trading Price [Member]
Share price | $ / shares		$ 13
Second Tranches Share Trading Price [Member]
Share price | $ / shares		16
Third Tranches Share Trading Price [Member]
Share price | $ / shares		19
Fourth Tranches Share Trading Price [Member]
Share price | $ / shares		$ 22
PIPE Investors [Member] | PIPE Subscription Agreements [Member]
Shares issued during the year, subscribed | shares		24,500,000
Shares issued during the year, aggregate purchase price		$ 245,000
Payments of stock issuance costs		$ 7,142
Old Spire Warrants [Member]
Class of warrant outstanding | shares	909,798
Old Spire Convertible Notes [Member]
Conversion ratio of convertible notes	2.4808
2021 Old Spire Notes [Member]
Conversion ratio of convertible notes	13.6466
Old Spire Series A Convertible Preferred Stock [Member]
Outstanding shares | shares	12,671,911
Common stock, conversion basis	one-to-one basis
Old Spire Series B Convertible Preferred Stock [Member]
Outstanding shares | shares	4,869,754
Common stock, conversion basis	one-to-one basis
Old Spire Series C Convertible Preferred Stock [Member]
Outstanding shares | shares	7,592,402
Common stock, conversion basis	one-to-one basis
New Spire Class A Common stock [Member]
Common stock per share | $ / shares		$ 0.0001
Exchange ratio of common stock		1.7058
Shares issued, price per share | $ / shares		$ 0.1236
New Spire Class B Common Stock [Member] | Old Spire Founders [Member]
Common stock per share | $ / shares		$ 0.0001

Revenue, Contract Assets, Con_3

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations - Schedule of Disaggregation of Revenue by Geography (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 9,561	$ 7,184	$ 28,390	$ 21,221
Revenue Benchmark [Member] | Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Concentration risk percentage	100.00%	100.00%	100.00%	100.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | EMEA [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 3,514	$ 2,909	$ 13,426	$ 10,149
Concentration risk percentage	37.00%	41.00%	47.00%	48.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Americas [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 4,805	$ 2,823	$ 10,561	$ 8,038
Concentration risk percentage	50.00%	39.00%	37.00%	38.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Asia Pacific [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1,242	$ 1,452	$ 4,403	$ 3,034
Concentration risk percentage	13.00%	20.00%	16.00%	14.00%

Revenue, Contract Assets, Con_4

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations - Schedule of Disaggregation of Revenue by Geography (Parenthetical) (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Netherlands [Member]
Disaggregation of Revenue [Line Items]
Concentration risk percentage	18.00%	25.00%	26.00%	36.00%
U.S. [Member]
Disaggregation of Revenue [Line Items]
Concentration risk percentage	50.00%	39.00%	37.00%	38.00%
Australia [Member]
Disaggregation of Revenue [Line Items]
Concentration risk percentage	11.00%	17.00%	11.00%	10.00%

Revenue, Contract Assets, Con_5

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenue From Contract With Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 9,561	$ 7,184	$ 28,390	$ 21,221
Contract assets	1,089		1,089		$ 853
Contract liabilities, current portion	10,331		10,331		$ 8,110
Revenue remaining performance obligation amount	$ 49,506		$ 49,506
Revenue performance obligation expected timing of satisfaction explantion			expects to recognize 70% of these future commitments over the next 12 months and the remaining 30% thereafter as revenue when the performance obligations are met.
Expected Time Of Satisfaction Over Next Twelve Months [Member]
Revenue From Contract With Customer [Line Items]
Revenue remaining performance obligation percentage	70.00%		70.00%
Expected Time Of Satisfaction Thereafter [Member]
Revenue From Contract With Customer [Line Items]
Revenue remaining performance obligation percentage	30.00%		30.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member]
Revenue From Contract With Customer [Line Items]
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
Data Solutions Contracts [Member]
Revenue From Contract With Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 4,926	$ 1,535	$ 13,000	$ 5,737
Data Solutions Contracts [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]
Revenue From Contract With Customer [Line Items]
Concentration Risk, Percentage	51.00%	21.00%	46.00%	27.00%
Space Services Solution Contracts [Member]
Revenue From Contract With Customer [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 4,640	$ 5,649	$ 15,395	$ 15,484
Space Services Solution Contracts [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]
Revenue From Contract With Customer [Line Items]
Concentration Risk, Percentage	49.00%	79.00%	54.00%	73.00%

Revenue, Contract Assets, Con_6

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations - Schedule of Changes in Contract Assets (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Change in Contract with Customer, Asset [Abstract]
Balance at January 1, 2021	$ 853
Contract assets recorded	900
Reclassified to Accounts receivable	(652)
Other	(12)
Balance at September 30, 2021	$ 1,089

Revenue, Contract Assets, Con_7

Revenue, Contract Assets, Contract Liabilities and Remaining Performance Obligations - Schedule of Changes in Contract Liabilities (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Change in Contract with Customer, Liability [Abstract]
Balance at the beginning of the year	$ 8,110	$ 4,550
Contract liabilities recorded during the period	9,037	4,645
Revenue recognized during the period	(6,624)	(1,208)
Other	(192)	0
Balance at the end of the period	$ 10,331	$ 7,987

Balance Sheet Components - Summ

Balance Sheet Components - Summary of Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Other Assets Current [Abstract]
Prepaid insurance	$ 6,083	$ 68
Technology and other prepaid contracts	1,687	767
Deferred contract costs	494	657
Prepaid rent	120	200
Other receivables	886	409
Other current assets	957	11
Other assets, current	$ 10,227	$ 2,112

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Other Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Other Accrued Liabilities [Abstract]
Professional services	$ 2,012	$ 420
Income taxes	709	105
Sales tax	26	122
Software	1,271	470
Satellite/launch/grounds material	829
Other	1,120	696
Other accrued expenses	$ 5,967	$ 1,813

Balance Sheet Components - Su_2

Balance Sheet Components - Summary of Property Plant and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 42,703	$ 35,700
Less: Accumulated depreciation and amortization	(28,113)	(23,260)
Property, Plant and Equipment, Other, Net	14,590	12,440
Property, Plant and Equipment, Net	25,855	20,458
Satellites in-service
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	32,076	26,196
Internally developed software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,166	2,166
Ground stations in-service
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,084	1,872
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,589	1,589
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,373	1,873
Computer equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,485	1,153
Computer software and website development
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	472	472
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	458	379
Satellite, launch and ground station work in progress
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Other, Net	$ 11,265	4,934
Finished satellites not in-service
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Other, Net		$ 3,084

Balance Sheet Components - Add

Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 2,075	$ 1,265	$ 5,615	$ 3,861
Amortization of internal use software	$ 0	$ 32	$ 34	$ 95

Long-Term Debt - Summary of Lon

Long-Term Debt - Summary of Long-term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 71,512	$ 31,443
Less: Debt issuance costs	(26,291)	(4,798)
Non-current portion of long-term debt	45,221	26,645
Eastward Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		15,000
EIB Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		14,734
PPP Loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		1,699
FP Term Loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	71,512	0
Other [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 10

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) € in Thousands, $ in Thousands	Sep. 30, 2021USD ($)shares	Sep. 24, 2021shares	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2021EUR (€)	Sep. 30, 2020USD ($)	Jun. 30, 2021USD ($)	May 17, 2021USD ($)	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Interest expense long term debt			$ 2,924	$ 309	$ 4,017		$ 1,063
Debt issuance costs, net	$ 26,291		26,291		26,291					$ 4,798
Gain (Loss) on extinguishment of Debt					(2,277)
Long-term Debt, Fair Value								$ 8,922
Issuance of shares to FP Credit Partners, L.P.	$ 14,803		$ 14,804		$ 22,868
EIB warrants [Member]
Debt Instrument [Line Items]
Number of trading days for determining volume-weighted average price		20 days
Expected settlement amount | €						€ 9,670
EIB warrants [Member] | Redemption of warrant Tranche B [Member]
Debt Instrument [Line Items]
Number of warrants to be cancelled | shares		775,966
FP Term Loan [Member]
Debt Instrument [Line Items]
Long term debt interest rate	9.00%		9.00%		9.00%
Debt conversion converted instrument common stock issued | shares	1,490,769
FP Term Loan [Member] | Debt Conversion Election Option Unexercised [Member]
Debt Instrument [Line Items]
Increase (Decrease) in Interest rate	4.00%
Eastward and EIB Loan Facility [Member] | Other Expense [Member]
Debt Instrument [Line Items]
Gain (Loss) on extinguishment of Debt					$ 4,954
PPP Loan [Member] | Other Expense [Member]
Debt Instrument [Line Items]
Gain (Loss) on extinguishment of Debt					$ 1,699
Credit Agreement With FP Credit Partners LP [Member] | FP Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument face amount									$ 70,000
Debt issuance costs, net									12,277
Amount held in restricted cash account for extinguishment of debt									$ 12,801
Long term debt interest rate									8.50%
Long-term debt maturity date	Apr. 15, 2026		Apr. 15, 2026		Apr. 15, 2026
Long term debt prepayment penalty	$ 17,500		$ 17,500		$ 17,500
Debt instrument covenant minimum unrestricted cash to be maintained	$ 15,000		15,000		15,000
Debt conversion converted instrument common stock issued | shares	977,723
Debt conversion, converted instrument amount	$ 8,065
Credit Agreement With FP Credit Partners LP [Member] | FP Term Loan [Member] | Maximum [Member]
Debt Instrument [Line Items]
Long term debt prepayment penalty	$ 49,000		$ 49,000		$ 49,000
Credit Agreement With FP Credit Partners LP [Member] | FP Term Loan [Member] | Debt Conversion Election Option Exercised [Member]
Debt Instrument [Line Items]
Increase (Decrease) in Interest rate	9.00%

Convertible Notes - Additional

Convertible Notes - Additional Information (Detail) $ in Thousands	1 Months Ended		2 Months Ended	3 Months Ended		9 Months Ended		16 Months Ended
	May 31, 2021	Dec. 31, 2012	Feb. 28, 2021USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Oct. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Debt issuance costs, net				$ 26,291		$ 26,291			$ 4,798
Stockholders' equity note, stock split, exchange ratio		1.8282
New Spire Class A Common stock [Member]
Debt Instrument [Line Items]
Stockholders' equity note, stock split, exchange ratio						1.7058
2019 and 2020 convertible notes [Member]
Debt Instrument [Line Items]
Proceeds from issuance of convertible debt								$ 42,884
Debt instrument interest rate stated percentage								8.00%
Debt instrument maturity date	Jul. 31, 2022							Jan. 29, 2022
Percentage of principal payment to be paid on maturity date if unconverted								5.00%
Debt issuance costs, net								$ 392
2021 convertible notes [Member]
Debt Instrument [Line Items]
Proceeds from issuance of convertible debt			$ 20,000
Debt instrument interest rate stated percentage			8.00%
Debt issuance costs, net			$ 62
Debt Instrument convertible conversion ratio						13.6466
Debt instrument term			4 years
Convertible notes payable [Member]
Debt Instrument [Line Items]
Accrued interest				0		$ 0			$ 5,944
Interest expense debt				$ 1,452	$ 1,182	1,550	$ 3,385
Debt Instrument, Increase, Accrued Interest						$ 1,698
2019 Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument convertible conversion ratio						2.4808
2020 Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument convertible conversion ratio						2.4808

Fair Value Measurement - Summar

Fair Value Measurement - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current Liabilities:
Warrant liability	$ 22,582	$ 0
Fair Value, Recurring [Member]
Long-term Liabilities:
Warrant liability	107,900
Fair Value, Recurring [Member] | Public Warrants [Member]
Long-term Liabilities:
Warrant liability	19,550
Fair Value, Recurring [Member] | Private Placement Warrants [Member]
Long-term Liabilities:
Warrant liability	11,220
Fair Value, Recurring [Member] | Contingent Earnoutliability Member [Member]
Long-term Liabilities:
Warrant liability	77,130
Fair Value, Recurring [Member] | E I B warrants [Member]
Current Liabilities:
Warrant liability	22,582
Fair Value, Recurring [Member] | Level 1 [Member]
Long-term Liabilities:
Warrant liability	19,550
Fair Value, Recurring [Member] | Level 1 [Member] | Public Warrants [Member]
Long-term Liabilities:
Warrant liability	19,550
Fair Value, Recurring [Member] | Level 2 [Member]
Long-term Liabilities:
Warrant liability	11,220
Fair Value, Recurring [Member] | Level 2 [Member] | Private Placement Warrants [Member]
Long-term Liabilities:
Warrant liability	11,220
Fair Value, Recurring [Member] | Level 2 [Member] | E I B warrants [Member]
Current Liabilities:
Warrant liability	22,582
Fair Value, Recurring [Member] | Level 3 [Member]
Long-term Liabilities:
Warrant liability	77,130
Fair Value, Recurring [Member] | Level 3 [Member] | Contingent Earnoutliability Member [Member]
Long-term Liabilities:
Warrant liability	$ 77,130
Fair Value, Recurring [Member] | Warrant Liabilities [Member]
Long-term Liabilities:
Warrant liability		4,007
Fair Value, Recurring [Member] | Warrant Liabilities [Member] | Level 3 [Member]
Long-term Liabilities:
Warrant liability		$ 4,007

Fair Value Measurement - Summ_2

Fair Value Measurement - Summary of Warrants Classified as Equity That Are Measured at Fair Value on Nonrecurring Basis (Detail) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Equity:
Warrants	$ 970	$ 970
Level 1 [Member]
Equity:
Warrants	0	0
Level 2 [Member]
Equity:
Warrants	0	0
Level 3 [Member]
Equity:
Warrants	$ 970	$ 970

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)$ / sharesshares
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Exercise price of warrants or rights | $ / shares	$ 11.50
EIB warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of days used for volume weighted average valuation method using the SPIR publicly traded price	20 days
Number of warrants or rights outstanding. | shares	1,551,933
Warrant redemption price per share | $ / shares	$ 0.0001
Series C Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Issuance of common stock upon exercise of warrants shares | shares	146,919
Exercise of series C preferred warrants | $	$ 891
Silicon Valley Bank [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Class of warrants or right issued during period | shares	32,412
Exercise price of warrants or rights | $ / shares	$ 1.60
Conversion of Silicon Valley Bank warrants to common stock | $	$ 308

Fair Value Measurement - Schedu

Fair Value Measurement - Schedule of Quantitative Information Regarding Warrant Liability (Detail)	Sep. 30, 2021$ / shares	Aug. 16, 2021$ / shares	Dec. 31, 2020$ / shares
Fair value of the Company's common stock [Member] | Private Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	12.53	9.93
Fair value of the Company's common stock [Member] | E I B warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	14.55		4.19
Fair value of the Company's common stock [Member] | Contingent Earnout Liability [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	12.53	9.93
Exercise price [Member] | Private Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	11.50	11.50
Exercise price [Member] | E I B warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.0001		0.0001
Risk-free interest rate [Member] | Private Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.98	0.75
Risk-free interest rate [Member] | E I B warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.98		0.13
Risk-free interest rate [Member] | Contingent Earnout Liability [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0.98	0.75
Expected volatility factor [Member] | Private Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	6	22
Expected volatility factor [Member] | E I B warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	70		68.4
Expected volatility factor [Member] | Contingent Earnout Liability [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	70	70
Expected Dividend yield [Member] | Private Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0	0
Expected Dividend yield [Member] | E I B warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0		0
Expected Dividend yield [Member] | Contingent Earnout Liability [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Measurement Input	0	0
Remaining contractual term (in years) [Member] | Private Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Term	4 years 10 months 17 days	5 years
Remaining contractual term (in years) [Member] | E I B warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Term	3 years 10 months 24 days		4 years 8 months 12 days
Remaining contractual term (in years) [Member] | Contingent Earnout Liability [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and Rights Outstanding, Term	1 day	1 day

Fair Value Measurement - Summ_3

Fair Value Measurement - Summary of Change in Fair Value of The Warrant Liabilities (Detail) - Level 3 [Member] - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance		$ 197
Issuance of warrants to Silicon Valley Bank		1,806
Ending balance		$ 2,003
Contingent Earnout Liability [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 0
Issuance of warrants to Silicon Valley Bank
Conversion of Silicon Valley Bank warrants to common stock
Exercise of series C preferred warrants
Contingent interest embedded derivative recognized relating to the FP Term Loan agreement
Contingent interest embedded derivative derecognized upon the execution of the FP Amendment
Contingent earnout liability recognized upon the closing of the reverse recapitalization	77,170
Change in fair value included in other income (expense), net
Transferred to Level 2 upon the closing of the reverse recapitalization
Ending balance	77,170
Contingent Interest Embedded Derivative [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	0
Issuance of warrants to Silicon Valley Bank
Conversion of Silicon Valley Bank warrants to common stock
Exercise of series C preferred warrants
Contingent interest embedded derivative recognized relating to the FP Term Loan agreement	8,922
Contingent interest embedded derivative derecognized upon the execution of the FP Amendment	(8,922)
Contingent earnout liability recognized upon the closing of the reverse recapitalization
Change in fair value included in other income (expense), net
Transferred to Level 2 upon the closing of the reverse recapitalization
Ending balance	0
Warrant Liability [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	4,007
Issuance of warrants to Silicon Valley Bank	308
Conversion of Silicon Valley Bank warrants to common stock	(308)
Exercise of series C preferred warrants	(891)
Contingent interest embedded derivative recognized relating to the FP Term Loan agreement
Contingent interest embedded derivative derecognized upon the execution of the FP Amendment
Contingent earnout liability recognized upon the closing of the reverse recapitalization
Change in fair value included in other income (expense), net	19,466
Transferred to Level 2 upon the closing of the reverse recapitalization	(22,582)
Ending balance	$ 0

Fair Value Measurement - Summ_4

Fair Value Measurement - Summary of Change in Fair Value of The Warrant Liabilities (Parenthetical) (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Change in fair value of warrant liabilities	$ 23,529
Warrant Liability [Member] | Other Nonoperating Income (Expense) [Member]
Change in fair value of warrant liabilities	$ 9,290	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Future Minimum Lease Payments For Noncancelable Operating Leases (Detail) $ in Thousands	Sep. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2021	$ 583
2022	2,372
2023	2,353
2024	2,231
2025	2,202
2026 and thereafter	5,062
Total	$ 14,803

Commitments and Contingencies_2

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Commitments And Contingencies Disclosure [Line Items]
Rent expence	$ 876	$ 313	$ 2,355	$ 1,684
Lease expire year			2029

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - 2012 Stock Option and Grant Plan [Member]	9 Months Ended	12 Months Ended
	Sep. 30, 2021$ / sharesshares	Dec. 31, 2020$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Stock Options outstanding at January 1, 2021 | shares	19,618,953
Number of Stock Options Granted | shares	4,676,898
Number of Stock Options Exercised | shares	799,901
Number of Stock Options Forfeited, canceled, or expired | shares	1,325,349
Number of Stock Options outstanding at September 30, 2021 | shares	22,170,601	19,618,953
Number of Stock Options Vested and expected to vest at September 30, 2021 | shares	22,170,601
Number of Stock Options Exercisable at September 30, 2021 | shares	10,895,186
Weighted- Average Exercise Price Options outstanding at January 1, 2021 | $ / shares	$ 1.78
Weighted- Average Exercise Price Granted | $ / shares	4.90
Weighted- Average Exercise Price Exercised | $ / shares	1.33
Weighted- Average Exercise Price Forfeited, canceled, or expired | $ / shares	2.50
Weighted- Average Exercise Price Options outstanding at September 30, 2021 | $ / shares	2.42	$ 1.78
Weighted- Average Exercise Price Vested and expected to vest at September 30, 2021 | $ / shares	2.42
Weighted- Average Exercise Price Exercisable at September 30, 2021 | $ / shares	$ 1.81
Weighted- Average Remaining Contractual Term Options outstanding	7 years 6 months	7 years 10 months 24 days
Weighted- Average Remaining Contractual Term Vested and expected to vest at September 30, 2021	7 years 6 months
Weighted- Average Remaining Contractual Term Exercisable at September 30, 2021	6 years 1 month 6 days

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of the Stock Based Compensation Expense based on Roles and Responsibilities of the Employees (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Expense	$ 2,099	$ 531	$ 6,600	$ 1,451
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Expense	31	9	75	26
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Expense	590	225	1,843	668
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Expense	550	74	1,278	219
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Expense	$ 928	$ 223	$ 3,404	$ 538

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	9 Months Ended
	Dec. 31, 2012	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation not yet recognized,expected to be recognised over a weighted average period		2 years 11 months 4 days
Weighted average grant date fair value of options granted		$ 2.94
Stockholders' equity note, stock split, exchange ratio	1.8282
Share-based compensation arrangement by share-based payment award, options, grants in period, grant date intrinsic value		$ 1,737
Share-based payment arrangement, non vested award, cost not yet recognized, amount		$ 17,903
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase Price of Common Stock, Percent	85.00%
2021 Equity Incentive Plan [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement,Number of shares available for grant under the plan	3,194,000
2021 Equity Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement,Number of shares available for grant under the plan	8,869,629
2021 Equity Incentive Plan [Member] | Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued under share-based payment arrangement	23,951,000
Percentage of Outstanding Stock Maximum	5.00%

Net Loss per Share - Schedule o

Net Loss per Share - Schedule of Earnings Per Share Basic and Diluted Attributable to Common Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net loss attributable to common stockholders	$ (32,701)	$ (7,624)	$ (79,261)	$ (22,340)
Denominator:
Weighted-average shares of New Spire Class A Common Stock used in computing basic and diluted net loss per share	67,348,269	17,605,469	37,389,424	17,603,874
Basic and diluted net loss per share (New Spire Class A Common Stock)	$ (0.49)	$ (0.43)	$ (2.12)	$ (1.27)

Net Loss per Share - Schedule_2

Net Loss per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	22,170,601	92,607,544
Convertible Preferred Stock (if-converted) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	42,726,773
Warrants For The Purchase Of Series C Convertible Preferred Stock (If-Converted) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	146,919
Warrants For The Purchase Of Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	1,285,078
Convertible Notes (if-converted) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	34,670,225
Stock Options To Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	22,170,601	13,778,549

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - EIB warrants [Member] € in Thousands, $ in Thousands	Nov. 08, 2021EUR (€)	Oct. 18, 2021EUR (€)shares	Oct. 14, 2021	Sep. 24, 2021shares	Sep. 30, 2021EUR (€)	Oct. 18, 2021USD ($)
Subsequent Event [Line Items]
Number of trading days for determining volume-weighted average price				20 days
Expected settlement amount					€ 9,670
Redemption of warrant Tranche B [Member]
Subsequent Event [Line Items]
Number of warrants to be cancelled | shares				775,966
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of trading days for determining volume-weighted average price			20 days
Expected settlement amount		€ 7,595
Restricted cash | $						$ 12,801
Subsequent Event [Member] | Redemption of warrant Tranche B [Member]
Subsequent Event [Line Items]
Number of warrants to be cancelled | shares		775,966
Subsequent Event [Member] | Redemption of warrant including Tranche A and Tranche B [Member]
Subsequent Event [Line Items]
Payment for redemption of warrant total	€ 17,265