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Balance Sheet Information - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2021 | Mar. 31, 2020 | Feb. 28, 2021 | Feb. 10, 2021
Condensed Balance Sheet Statements Captions [Line Items] |  |  |  |  |  |
Depreciation expense | $ 20,400 | $ 20,100 | $ 40,600 | $ 40,300 |  |
Estimated initial equity warrant asset value |  |  |  |  |  | $ 16,400
Warrant asset value | $ 16,374 |  | $ 16,374 |  |  |
Archer Aviation, Inc. [Member] |  |  |  |  |  |
Condensed Balance Sheet Statements Captions [Line Items] |  |  |  |  |  |
Equity warrant assets, right to acquire common stock shares |  |  |  |  | 1,171,649 |

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- Definition Equity warrant assets, right to acquire common stock shares. + References No definition available. + Details
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- Definition Estimated initial equity warrant asset value. + References No definition available. + Details
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- Details
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