Significant Accounting Policies	6 Months Ended
Jun. 30, 2025
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	Significant Accounting Policies Basis of Presentation The accompanying unaudited consolidated financial statements of BOK Financial have been prepared in accordance with accounting principles for interim financial information generally accepted in the United States and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. The unaudited consolidated financial statements include accounts of BOK Financial and its subsidiaries, principally BOKF, NA, BOK Financial Securities, Inc., and BOK Financial Private Wealth, Inc. Operating divisions of BOKF, NA include Bank of Albuquerque, Bank of Oklahoma, Bank of Texas, BOK Financial in Arizona, Arkansas, Colorado, and Kansas/Missouri, BOK Financial Mortgage, and the TransFund electronic funds network. Certain reclassifications have been made to conform to the current period presentation. The financial information should be read in conjunction with BOK Financial's 2024 Form 10-K filed with the Securities and Exchange Commission, which contains audited financial statements. Amounts presented as of December 31, 2024, have been derived from the audited financial statements included in BOK Financial's 2024 Form 10-K but do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. Operating results for the six-month period ended June 30, 2025, are not necessarily indicative of the results that may be expected for the year ending December 31, 2025. Newly Adopted and Pending Accounting Policies Financial Accounting Standards Board FASB ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures The FASB issued ASU 2023-09 on December 14, 2023, which amends income tax disclosures to provide information to better assess how an entity’s operations and related tax risks and tax planning and operational opportunities affect its tax rate and prospects for future cash flows. The new guidance requires the entity to disclose specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. ASU 2023-09 is effective for annual periods beginning after December 15, 2024. The Company is currently assessing the impact ASU 2023-09 will have on its income tax disclosures. FASB ASU 2024-01, Compensation—Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards The FASB issued ASU 2024-01 on March 21, 2024, which provides illustrative guidance to help entities determine whether profits interest and similar awards should be accounted for as share-based payment arrangements within the scope of Topic 718, Compensation—Stock Compensation. The ASU is effective for annual periods beginning after December 15, 2024, including interim periods within those annual periods. Adoption of ASU 2024-01 did not have a material effect on the Company's financial statements. FASB ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses The FASB issued ASU 2024-03 on November 4, 2024, which amends the disclosure of certain costs and expenses. The amendments intend to bring improvement by requiring further disaggregation of expenses that are not already required to be disclosed in the notes to the financial statements at interim and annual reporting periods. ASU 2024-03 is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. The Company is currently assessing the impact ASU 2024-03 will have on its expense disclosures.

The accompanying unaudited consolidated financial statements of BOK Financial have been prepared in accordance with accounting principles for interim financial information generally accepted in the United States and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included.

The unaudited consolidated financial statements include accounts of BOK Financial and its subsidiaries, principally BOKF, NA, BOK Financial Securities, Inc., and BOK Financial Private Wealth, Inc. Operating divisions of BOKF, NA include Bank of Albuquerque, Bank of Oklahoma, Bank of Texas, BOK Financial in Arizona, Arkansas, Colorado, and Kansas/Missouri, BOK Financial Mortgage, and the TransFund electronic funds network.

The financial information should be read in conjunction with BOK Financial's 2024 Form 10-K filed with the Securities and Exchange Commission, which contains audited financial statements. Amounts presented as of December 31, 2024, have been derived from the audited financial statements included in BOK Financial's 2024 Form 10-K but do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. Operating results for the six-month period ended June 30, 2025, are not necessarily indicative of the results that may be expected for the year ending December 31, 2025.

The FASB issued ASU 2023-09 on December 14, 2023, which amends income tax disclosures to provide information to better assess how an entity’s operations and related tax risks and tax planning and operational opportunities affect its tax rate and prospects for future cash flows. The new guidance requires the entity to disclose specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. ASU 2023-09 is effective for annual periods beginning after December 15, 2024. The Company is currently assessing the impact ASU 2023-09 will have on its income tax disclosures.

The FASB issued ASU 2024-01 on March 21, 2024, which provides illustrative guidance to help entities determine whether profits interest and similar awards should be accounted for as share-based payment arrangements within the scope of Topic 718, Compensation—Stock Compensation. The ASU is effective for annual periods beginning after December 15, 2024, including interim periods within those annual periods. Adoption of ASU 2024-01 did not have a material effect on the Company's financial statements.

FASB ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses

The FASB issued ASU 2024-03 on November 4, 2024, which amends the disclosure of certain costs and expenses. The amendments intend to bring improvement by requiring further disaggregation of expenses that are not already required to be disclosed in the notes to the financial statements at interim and annual reporting periods. ASU 2024-03 is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. The Company is currently assessing the impact ASU 2024-03 will have on its expense disclosures.