Unrestricted Net Assets - Condensed Financial Information on Financial Position (Parenthetical) (Detail) - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Condensed Financial Information on Financial Position [Line Items]
Common stock, par value	$ 0.001	$ 0.001
Common shares authorized	400,000,000	400,000,000
Common shares issued	95,464,000	55,464,000
Common shares outstanding	95,464,000	55,464,000
Stockholders equity reverse stock split	2-for-1
Northann Corp [Member]
Condensed Financial Information on Financial Position [Line Items]
Stockholders equity reverse stock split	2-for-1	2-for-1
Northann Corp [Member] \| Common Stock [Member]
Condensed Financial Information on Financial Position [Line Items]
Common stock, par value	$ 0.001	$ 0.001
Common shares authorized	400,000,000	400,000,000
Common shares issued	95,464,000	55,464,000
Common shares outstanding	95,464,000	55,464,000
Series A Preferred Stock [Member]
Condensed Financial Information on Financial Position [Line Items]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred shares authorized	100,000,000	100,000,000
Preferred shares issued	10,000,000	10,000,000
Preferred shares outstanding	10,000,000	10,000,000
Series A Preferred Stock [Member] \| Northann Corp [Member]
Condensed Financial Information on Financial Position [Line Items]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred shares authorized	100,000,000	100,000,000
Preferred shares issued	10,000,000	10,000,000
Preferred shares outstanding	10,000,000	10,000,000

Condensed financial information on financial position.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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- Definition

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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