BlackSky Technology Inc. General form of registration statement for all companies including face-amount certificate companies

Related Party Transactions - (Parenthetical) (Detail)

v3.21.2

Related Party Transactions - (Parenthetical) (Detail) $ in Thousands, shares in Millions		6 Months Ended	12 Months Ended
	Feb. 28, 2021 USD ($)	Jun. 30, 2019 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2017	Jun. 30, 2017
Related Party Transaction [Line Items]
Long-term Debt, Gross			$ 123,044		$ 180,259	$ 103,435
Seahawk LSA [Member] \| Blacksky Technology [Member]
Related Party Transaction [Line Items]
Long-term Debt, Gross		$ 18,400	$ 18,446		19,198	19,198
Class of warrant or right, issued during the period \| shares		13.5	13.5
Intelsat [Member] \| Blacksky Technology [Member]
Related Party Transaction [Line Items]
Long-term Debt, Gross		$ 50,000	$ 50,000		52,039	52,039
Class of warrant or right, issued during the period \| shares		20.2	20.2
Jason And Marian Joh Andrews [Member] \| Blacksky Technology [Member]
Related Party Transaction [Line Items]
Long-term Debt, Gross			$ 12,500		$ 11,750	$ 12,500
Notes issued				$ 12,500
Stock repurchased during period, shares \| shares				11.5
X-Bow [Member] \| Blacksky Technology [Member]
Related Party Transaction [Line Items]
Debt Instrument, Interest Rate, Stated Percentage							20.60%	20.60%
Mithril II LLP [Member] \| Blacksky Technology [Member]
Related Party Transaction [Line Items]
Notes issued	$ 15,000
VCVC Four LLC [Member] \| Blacksky Technology [Member] \| 2021 Convertible Bridge Notes as converted in common stock [Member]
Related Party Transaction [Line Items]
Debt instrument face value	$ 5,000
Number of shares of common stock issuable on debt conversion as a percentage of common stock shares outstanding					0.70%
Common Stock Shares Issued Per Dollar	7

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Common stock shares issued per dollar.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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