Recently Adopted and Issued Accounting Standards	9 Months Ended
Recently Adopted and Issued Accounting Standards	Sep. 30, 2025
Accounting Policies [Abstract]
Recently Adopted and Issued Accounting Standards	Recently Adopted and Issued Accounting Standards Accounting Standards Adopted in 2025 We have not adopted any new accounting standards during the nine months ended September 30, 2025. Accounting Standards Not Yet Adopted In December 2023, the Financial Accounting Standards Board "FASB" issued Accounting Standards Update "ASU" No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The amendments require disaggregated information about the effective tax rate reconciliation and additional disclosures on reconciling items and taxes paid that meet a quantitative threshold. The amendments are effective for annual reporting periods beginning after December 15, 2024, and may be adopted either prospectively or retrospectively. Early adoption is permitted. The Company expects this ASU to only impact its disclosure requirements (i.e. 2025 Form 10-K) and does not expect the adoption of this ASU to have a material impact on its business operations or Consolidated Statements of Financial Condition. In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. The amendments are intended to improve income statement expense disclosure requirements, primarily through enhanced disclosures about certain costs and expenses included in income statement expense captions. The amendments are effective for annual reporting periods beginning after December 15, 2026 (i.e., 2027 Form 10-K) and interim periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the impact of the amendments on its financial statement disclosures, and does not expect the adoption to have a material impact on its business operations or Consolidated Statements of Financial Condition. In May 2025, the FASB issued ASU 2025-03, Business Combinations (Topic 805) and Consolidation (Topic 810): Determining the Accounting Acquirer in the Acquisition of a Variable Interest Entity, which revises current guidance for determining the accounting acquirer for a transaction effected primarily by exchanging equity interests in which the legal acquiree is a variable interest entity that meets the definition of a business. The amendments require that an entity consider the same factors that are currently required for determining which entity is the accounting acquirer in other acquisition transactions. ASU 2025-03 is effective for the Company's annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods, with early adoption permitted. ASU 2025-03 is required to be applied prospectively. The Company is evaluating the impact of this update on its financial statements and related disclosures, and does not expect the adoption to have a material impact on its business operations or Consolidated Statements of Financial Condition. In May 2025, the FASB issued ASU 2025-04, Compensation – Stock Compensation (Topic 718) and Revenue From Contracts With Customers (Topic 606): Clarifications to Share-Based Consideration Payable to a Customer, to clarify guidance in Topic 606 and Topic 718 related to share-based payments made as consideration payable to a customer. This amendment revises the Master Glossary definition of a performance obligation to include conditions tied to a customer’s purchases or those of other parties within the distribution chain. This revised definition applies only to share-based consideration payable to customers and cannot be analogized to awards granted to employees or nonemployees. Additionally, the amendment clarifies that grantors must evaluate the likelihood of vesting using Topic 718 alone and should not apply the variable consideration constraints from Topic 606. ASU 2025-04 is effective for the Company's annual reporting periods beginning after Dec. 15, 2026, and interim reporting periods within those annual reporting periods, with early adoption permitted. The Company is evaluating the impact of this update on its financial statements and related disclosures, and does not expect the adoption to have a material impact on its business operations or Consolidated Statements of Financial Condition.

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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Bank of Marin Bancorp 10-Q