v3.25.3

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Investment securities:
Estimated fair value	$ 2,185.4	$ 2,358.6
Stockholders' equity:
Nonvoting, noncumulative preferred stock, shares authorized (in shares)	100,000	100,000
Nonvoting, noncumulative preferred stock, shares issued (in shares)	0	0
Nonvoting, noncumulative preferred stock, shares outstanding (in shares)	0	0
Preferred Stock, Shares Outstanding	0	0
Shares outstanding (in shares)	103,967,257	104,585,964
Common Stock, Shares, Issued	103,967,257	104,585,964
Common Stock, Shares Authorized	150,000,000	150,000,000
Common Stock, Par or Stated Value Per Share	$ 0.00001	$ 0.00001

Face amount or stated value per share of common stock.

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

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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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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FIRST INTERSTATE BANCSYSTEM INC 10-Q