Business Overview [Line Items]

No definition available.

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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public before deducting issuance costs.

+ References

No definition available.

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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

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- Definition

Amount of accumulated undistributed earnings (deficit).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Business Overview (Narrative) (Details) $ / shares in Units, $ in Thousands	Aug. 11, 2025 USD ($) $ / shares shares	Jul. 31, 2025	Jul. 17, 2025	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Business Overview [Line Items]
Stock split ratio		0.3425
Accumulated deficit				$ 1,087,750	$ 970,959	$ 1,100
Cash and cash equivalents and investments in available-for-sale securities				$ 280,200
HeartFlow Holding, Inc. [Member]
Business Overview [Line Items]
Stock split ratio			1
IPO [Member]
Business Overview [Line Items]
Shares issued \| shares	19,166,667
Shares issued, price per share \| $ / shares	$ 19.00
Gross proceeds from issuance of shares	$ 364,200
Payment of stock issuance costs	$ 31,800
Underwriter [Member]
Business Overview [Line Items]
Shares issued \| shares	2,500,000