Total loans and leases Total loans Total loans Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process Schedule of Amount of Gross Unrealized Losses for Debt Securities and Estimated Fair Value Debt Securities, Available-for-Sale [Table Text Block] Customer commodity derivatives Commodity Contract [Member] Amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date [Abstract] Less: Cash collateral pledged/received Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset Award Timing Predetermined Award Timing Predetermined [Flag] Entity File Number Entity File Number Accumulated paid-in capital Additional Paid-in Capital [Member] Interest-bearing: Interest-Bearing Deposit Liabilities [Abstract] Tabular List, Table Tabular List [Table Text Block] Recent Accounting Pronouncements and Developments New Accounting Pronouncements, Policy [Policy Text Block] Schedule of Carrying Values and Estimated Fair Values Fair Value, by Balance Sheet Grouping [Table Text Block] Loans acquired in purchase of California branches, net (at time of purchase) Loans Assumed Measurement Basis [Axis] Measurement Basis [Axis] Adjustment to Compensation: Adjustment to Compensation [Axis] Total unfunded lending commitments Total Unfunded Lending Commitments Total Unfunded Lending Commitments Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] REVENUE FROM CONTRACTS WITH CUSTOMERS Revenue from Contract with Customer [Text Block] Unrealized loss amortization associated with the securities transferred from AFS to HTM, before tax OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI for Amortization of Gain (Loss), before Tax Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Recoveries Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery Other liabilities: Other Liabilities [Abstract] Stock, Class of Stock [Table] Stock, Class of Stock [Table] Losses from fair value changes Fair Value, Option, Changes in Fair Value, Gain (Loss) Less: Cash collateral pledged/received Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset Allowance for loan losses Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] Due after one year through five years Debt Securities, Held-to-Maturity, Amortized Cost Excluding Accrued Interest, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year One through Five Adjustment to Compensation, Amount Adjustment to Compensation Amount Change in other assets Decrease in other assets Increase (Decrease) in Other Operating Assets Share-based compensation Share-Based Payment Arrangement, Noncash Expense Par value of hedged items Derivative Asset, Notional Amount Stock options Share-Based Payment Arrangement, Option [Member] Leasing Finance Leases Portfolio Segment [Member] Decrease in short-term borrowings Increase (Decrease) In Short Term Debt Increase (Decrease) In Short Term Debt Asset Pledged as Collateral without Right Asset Pledged as Collateral without Right [Member] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Dividends on common stock Dividends, Common Stock, Cash Total shareholders’ equity Balance at beginning of period Balance at end of period Accumulated other comprehensive loss Equity, Attributable to Parent Due after five years through ten years Debt Securities, Held-to-Maturity, Amortized Cost Excluding Accrued Interest, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 5 through 10 Measurement Frequency [Axis] Measurement Frequency [Axis] Other comprehensive income, net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Less undistributed earnings applicable to nonvested shares Undistributed Earnings Applicable to Nonvested Shares Undistributed Earnings Applicable to Nonvested Shares Nevada NEVADA Terminated or redesignated, unamortized basis adjustments, assets Terminated And Redesignated Swaps, Unamortized Basis Adjustments, Assets Terminated And Redesignated Swaps, Unamortized Basis Adjustments, Assets Fair Value, Recurring Fair Value, Recurring [Member] New Mexico NEW MEXICO LIABILITIES AND SHAREHOLDERS’ EQUITY LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity [Abstract] Cover [Abstract] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Maximum Maximum [Member] Available-for-sale, total, estimated fair value Debt Securities, Available-for-Sale, Unrealized Loss Position Due after ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Financing Receivable, Credit Quality Indicator [Table] Number of branches owned Number of Branches Owned Number of Branches Owned Oregon OREGON Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Due after ten years Debt Securities, Held-to-Maturity, Weighted Average Yield, Maturity, after Year 10 Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Weighted-average term extension (in months) Financing Receivable, Modified, Weighted Average Term Increase from Modification Entity Shell Company Entity Shell Company Revolving loans converted to term loans amortized cost basis Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan Federal funds sold and securities purchased under agreements to resell Federal Funds Sold and Securities Purchased under Agreements to Resell Total debt securities Debt Securities, Available-for-Sale, Maturity, Weighted Average Yield Debt Securities, Available-for-Sale, Maturity, Weighted Average Yield Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Operating Segments Operating Segments [Member] Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Total interest expense Interest Expense, Operating 30-89 days past due Financial Asset, 30 to 89 Days Past Due [Member] Financial Asset, 30 to 89 Days Past Due Texas TEXAS Income before income taxes Income (loss) before income taxes Income (Loss) from Continuing Operations before Income Taxes, Domestic 1-4 family residential One Through Four Family Residential [Member] One through four Family Residential [Member] Document Fiscal Period Focus Document Fiscal Period Focus Goodwill and intangibles Intangible Assets, Net (Including Goodwill) Single family residential Single Family Residential [Member] Single Family Residential Interest on securities Interest Income, Debt Securities, Operating Award Timing Method Award Timing Method [Text Block] Nonaccrual loans that are current Nonaccrual loans that are current Financing Receivable, Excluding Accrued Interest, Nonaccrual Award Type Award Type [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Due in one year or less Debt Securities, Available-for-Sale, Weighted Average Yield, Maturity, Year One Savings and money market Deposits, Savings and Money Market Deposits, Savings and Money Market Trading Symbol Trading Symbol 2030 Lessee, Operating Lease, Liability, to be Paid, Year Four Due after five years through ten years Debt Securities, Amortized Cost, Maturity, Allocated And Single Maturity Date, After Year 5 Through 10 Debt Securities, Amortized Cost, Maturity, Allocated And Single Maturity Date, After Year 5 Through 10 Due after ten years Debt Securities, Available-for-Sale, Weighted Average Yield, Maturity, after Year 10 Net activity under employee plans and related tax benefits (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Entity Address, City or Town Entity Address, City or Town Utah UTAH Finance leases Finance Lease, Weighted Average Discount Rate, Percent Marketable Securities [Line Items] Marketable Securities [Line Items] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Construction and other consumer real estate Construction And Other Consumer Real Estate [Member] Construction And Other Consumer Real Estate [Member] Net change in short-term borrowed funds Proceeds from (Repayments of) Short-Term Debt Credit-related expense Credit And Collection Services Credit and collection services. Restricted stock and restricted stock units Restricted Stock Units (RSUs) [Member] Allowance for Credit Losses Credit Loss, Financial Instrument [Policy Text Block] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Emerging Growth Company Entity Emerging Growth Company Finance leases Finance Lease, Weighted Average Remaining Lease Term Total allowance for credit losses Financing Receivable And Off Balance Sheet Liability, Allowance For Credit Loss Financing Receivable And Off Balance Sheet Liability, Allowance For Credit Loss Due after one year through five years Debt Securities, Available-for-Sale, Weighted Average Yield, Maturity, after Year One Through Five Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Total income statement impact Derivative, Gain (Loss) on Derivative, Net Total noninterest income Total noninterest income Noninterest Income Common stock, outstanding shares (in shares) Balance at beginning of period (in shares) Balance at end of period (in shares) Common Stock, Shares, Outstanding Available-for-sale, Unrealized Gains, Other Available-for-sale, Unrealized Gains, Other [Member] Available-for-sale, Unrealized Gains, Other Held-to-maturity Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss Noninterest expense: Noninterest Expense [Abstract] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Cash and due from banks Cash and Due from Banks Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] 90+ days past due Financing Receivable, Excluding Accrued Interest, 90 Days or More Past Due, Still Accruing Total income from loans sold Gain (Loss) on Sale of Financing Receivable Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Derivative Instruments and Hedging Activities Disclosure [Abstract] Weighted-average interest rate reduction (in percentage points) Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification Pledged Status [Domain] Pledged Status [Domain] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Income taxes Less: Income tax expense (benefit) Income Tax Expense (Benefit) Other assets * Other Assets Fair value of assets, beginning balance Fair value of assets, ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Document Information [Line Items] Document Information [Line Items] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Derivatives designated as accounting hedges: Designated as Hedging Instrument [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Axis] Terminated or redesignated, unamortized basis adjustments, debt Terminated And Redesignated Swaps, Unamortized Basis Adjustments, Debt Terminated And Redesignated Swaps, Unamortized Basis Adjustments, Debt Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Liabilities for Guarantees on Long-Duration Contracts [Table] Liabilities for Guarantees on Long-Duration Contracts [Table] Acquisition of California branches, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Noncustomer-related noninterest income Noninterest Income, Other Operating Income Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Available-for-sale, at fair value Available-for-sale Debt Securities, Available-for-Sale, Excluding Accrued Interest Cost of investments sold Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Subsequent Event Subsequent Event [Member] Net interest income Net interest income Interest Income (Expense), Operating Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Retail and business banking fees Products And Services, Retail And Business Banking Fees [Member] Products And Services, Retail And Business Banking Fees PEO Total Compensation Amount PEO Total Compensation Amount Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Derivatives Other liabilities Derivative Liability, Subject to Master Netting Arrangement, before Offset Number of civil cases Number of Civil Cases Number of Civil Cases Equity Components [Axis] Equity Components [Axis] 2023 2022 Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year Financial Standby Letters of Credit [Member] Commercial account fees Commercial account fees Commercial account fees Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Interest on securities Investment Income, Debt Securities Excluding Trading Securities, Operating Investment Income, Debt Securities Excluding Trading Securities, Operating Number of reportable segments Number of Reportable Segments Washington WASHINGTON Entity Address, State or Province Entity Address, State or Province Total interest income Interest and Dividend Income, Operating Undistributed earnings applicable to common shares Undistributed Earnings (Loss) Available to Common Shareholders, Diluted Special Mention Special Mention [Member] Financing Receivables, Period Past Due [Domain] Financial Asset, Aging [Domain] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Individual: Individual [Axis] Hedges of fixed-rate liabilities Hedges Of Fixed-Rate Liabilities [Member] Hedges Of Fixed-Rate Liabilities Net decrease (increase) in loans held for sale Increase (Decrease) in Loan, Held-for-Sale Principal forgiveness Principal Forgiveness [Member] Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Wyoming WYOMING LEASES Lessor, Sales-type Leases [Text Block] Entity Interactive Data Current Entity Interactive Data Current Gross charge-offs by year of loan origination Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] Change in other liabilities Decrease in other liabilities Increase (Decrease) in Operating Liabilities Available-for-sale Interest Income, Debt Securities, Available-for-Sale, Operating Financing Receivable, Modifications [Line Items] Financing Receivable, Modified [Line Items] Home equity credit line Home Equity Line of Credit [Member] Interest income: Interest and Dividend Income, Operating [Abstract] Nonaccrual Nonaccrual [Member] Nonaccrual Total noninterest expense Noninterest Expense Due after one year through five years Debt Securities, Held-to-Maturity, Weighted Average Yield, Maturity, after Year One Through Five Payment deferral Payment Deferral [Member] Interest on deposits Interest Expense, Deposits Noninterest income: Noninterest Income [Abstract] Interest on fair value hedges Other Noninterest Income/(Expense) Derivative Instrument, Noninterest Income (Expense) Derivative instrument noninterest income (expense) Entity Central Index Key Entity Central Index Key Due after ten years Debt Securities, Weighted Average Yield, Maturity, After Year 10 Debt Securities, Weighted Average Yield, Maturity, After Year 10 PEO Name PEO Name Total customer-related noninterest income Revenues Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Other noninterest income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Noninterest Income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Noninterest Income Summary of Outstanding Loan Balances (Accruing and Nonaccruing) Categorized by Credit Quality Indicators Financing Receivable Credit Quality Indicators [Table Text Block] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Schedule of Investment Securities Summary of Investment Securities [Table Text Block] Summary of Investment Securities [Table Text Block] Number of branches Number of Branches Number of Branches Noninterest-bearing demand Noninterest-Bearing Deposit Liabilities Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Office building Office Building [Member] Netting Derivative Asset, Subject to Master Netting Arrangement, Gross Liability and Collateral, Obligation to Return Cash, Offset Schedule of Derivative Amounts Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Operating leases Lessee, Operating Lease, Description [Abstract] Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Class of Stock [Domain] Class of Stock [Domain] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Hedges of floating-rate liabilities Hedges Of Floating-Rate Liabilities [Member] Hedges Of Floating-Rate Liabilities Commitments, Guarantees, and Contingent Liabilities [Abstract] Guarantees, Commitments And Contingencies [Abstract] Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged items Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease) Real estate acquired through foreclosure (prior year less than) Real Estate Acquired Through Foreclosure Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Number of states in which entity operates Number of States in which Entity Operates Entity Address, Address Line One Entity Address, Address Line One Accumulated other comprehensive income (loss) Total AOCI Attributable to Parent [Member] Securities sold, not yet purchased Financial Instruments Sold, Not yet Purchased, at Fair Value Preferred stock dividends Other Preferred Stock Dividends and Adjustments Standby letters of credit Letters Of Credit Standby Letters of credit standby. Revolving loans converted to term loans gross charge-offs Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Reserve for unfunded lending commitments Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES Derivative Instruments and Hedging Activities Disclosure [Text Block] Fair Value as of Grant Date Award Grant Date Fair Value Undistributed earnings Undistributed Earnings, Basic 2022 2020 Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year Schedule of Lease Related Assets and Liabilities Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee Schedule of Long-term Debt Schedule of Long-Term Debt Instruments [Table Text Block] Salaries and employee benefits Labor and Related Expense Document Quarterly Report Document Quarterly Report Available-for-sale, less than 12 Months, estimated fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Long-term debt Long-Term Debt, Fair Value Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Due after five years through ten years Debt Securities, Available-for-Sale, Weighted Average Yield, Maturity, after Year 5 Through 10 Summary of Nonaccrual Loans Financing Receivable, Nonaccrual [Table Text Block] 2028 Lessee, Operating Lease, Liability, to be Paid, Year Two Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration] Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration] Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Non-PEO NEO Non-PEO NEO [Member] Noninterest income Noninterest Income, Adjusted Noninterest Income, Adjusted Finance leases Lessee, Finance Lease, Description [Abstract] Net decrease in money market investments Payments for (Proceeds from) Short-Term Investments Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Due after five years through ten years Debt Securities, Weighted Average Yield, Maturity, After Year 5 Through 10 Debt Securities, Weighted Average Yield, Maturity, After Year 5 Through 10 Par value of hedged liabilities Derivative Liability, Notional Amount Available-for-sale Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax All Award Types Award Type [Domain] 2027 Lessee, Operating Lease, Liability, to be Paid, Year One Effective portion of derivative gain/(loss) deferred in AOCI Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Zions Bank Zions Bank Segment [Member] Zions Bank Segment [Member] Equity Awards Adjustments Equity Awards Adjustments [Member] Other, net Other Noncash Income (Expense) Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Compensation Amount Outstanding Recovery Compensation Amount Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Foreign exchange derivatives Foreign Exchange Contract [Member] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Fair value Estimate of Fair Value Measurement [Member] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Due after one year through five years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Small Business Administration loan-backed securities Small Business Administration Loan Backed Securities [Member] Small Business Administration Loan-Backed Securities [Member] Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Due after five years through ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Long-term debt Total Long-Term Debt and Lease Obligation Dilutive effect of stock options (in shares) Dilutive Effect of Stock Options Dilutive Effect of Stock Options Financial Instruments [Domain] Financial Instruments [Domain] Purchases Fair Value, Measurement with 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applicable to common shares Net Income (Loss) Available to Common Stockholders, Diluted Collateral Held [Domain] Collateral Held [Domain] Diluted shares (in shares) Weighted average diluted common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] CB&T California Bank And Trust Segment [Member] California Bank And Trust Segment [Member] Derivative [Table] Derivative [Table] Money market investments: Restricted Cash and Investments [Abstract] Entity Small Business Entity Small Business Income Tax Disclosure [Abstract] Series A Floating-Rate Non-Cumulative Perpetual Preferred Stock Series A Floating-Rate Non-Cumulative Perpetual Preferred Stock [Member] Series A Floating-Rate Non-Cumulative Perpetual Preferred Stock Preferred stock outstanding (in shares) Preferred Stock, Shares Outstanding Document Transition Report Document Transition Report Liabilities for Guarantees on Long-Duration Contracts [Line Items] Liabilities for Guarantees on Long-Duration Contracts [Line Items] Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Due in one year or less Debt Securities, Held-to-Maturity, Weighted Average Yield, Maturity, Year One Capital markets fees and income Products And Services, Capital Markets And Foreign Exchange Fees [Member] Products And Services, Capital Markets And Foreign Exchange Fees Underlying Securities Award Underlying Securities Amount Available-for-sale, gross gains Debt Securities, Available-for-Sale, Realized Gain Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date Total available-for-sale Debt Securities, Available For Sale, Excluding Accrued Interest [Member] Debt Securities, Available For Sale, Excluding Accrued Interest Subsequent Events Subsequent Events, Policy [Policy Text Block] INCOME TAXES Income Tax Disclosure [Text Block] Weighted average remaining lease term (years) Weighted Average Remaining Lease Term [Abstract] Weighted Average Remaining Lease Term Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Schedule of Interest Income by Security Type Tax and Nontaxable Interest Income by Investment Type [Table Text Block] [Table Text Block] for Tax and Nontaxable Interest Income by Investment Type [Table] Hedges of floating-rate assets Hedges Of Floating-Rate Assets [Member] Hedges Of Floating-Rate Assets Shares repurchased (in dollars per share) Shares Acquired, Average Cost Per Share Document Type Document Type Level 3 Fair Value, Inputs, Level 3 [Member] NET EARNINGS PER COMMON SHARE Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Marketable Securities [Table] Marketable Securities [Table] Product and Service [Axis] Product and Service [Axis] Revolving loans gross charge-offs Financing Receivable, Excluding Accrued Interest, Revolving, Writeoff Total noninterest income from contracts with customers Revenue from Contract with Customer, Excluding Assessed Tax Total investment securities Gross Unrealized Gains of Investment Securities Recognized in OCI Gross Unrealized Gains of Investment Securities Recognized in OCI Loans sold from held for sale Proceeds from Sale, Loan, Held-for-Sale Investment Income [Table] Investment Income [Table] Range [Axis] Statistical Measurement [Axis] Retail and business banking fees Retail and business banking fees Retail and business banking fees Total debt securities Debt Securities, Held-to-Maturity, Maturity, Weighted Average Yield Debt Securities, Held-to-Maturity, Maturity, Weighted Average Yield Share repurchase program, authorized amount Share Repurchase Program, Authorized, Amount 2025 2024 Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff Ag loan servicing Servicing Contracts [Member] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Nonaccrual loans that are current Financial Asset, 1 to 29 Days Past Due [Member] Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Net earnings applicable to common shareholders Net Income (Loss) Available to Common Stockholders, Basic Average yield Debt Securities, Available-for-Sale, Weighted Average Yield, Maturity [Abstract] Other comprehensive income, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Schedule of Derivative Gains (Losses) Deferred in OCI or Recognized in Earnings Derivative Instruments, Gain (Loss) [Table Text Block] Customer-facing interest rate derivatives Interest Rate Swaps For Customers [Member] Interest Rate 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