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Fair Value Measurements, Fair Value Of Financial Instruments as Measured On a Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | --- | --- | ---
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | $ 5,212,791 |  |  | $ 5,193,505 |  |  |  |
Available for sale securities | 12,793,784 |  |  | 12,286,681 |  |  |  |
Fair value option securities | 19,050 |  |  | 20,671 |  |  |  |
Mortgage servicing rights | 333,246 |  | $ 319,330 | 293,884 |  | $ 304,722 | $ 299,803 | $ 277,608
Derviative contracts, net of cash collateral, Assets, Fair value | 225,076 |  |  | 410,304 |  |  |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 287,509 |  |  | 587,473 |  |  |  |
U.S. government securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 71,169 |  |  | 10,959 |  |  |  |
Residential agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 5,023,892 |  |  | 5,105,137 |  |  |  |
Available for sale securities | 8,108,567 |  |  | 6,834,720 |  |  |  |
Fair value option securities | 19,050 |  |  | 20,671 |  |  |  |
Municipal securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 56,780 |  |  | 37,413 |  |  |  |
Available for sale securities | 278,043 |  |  | 502,833 |  |  |  |
U.S. Treasury [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 923 |  |  | 925 |  |  |  |
Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 828,049 |  |  | 799,877 |  |  |  |
Commercial agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 3,577,729 |  |  | 4,147,853 |  |  |  |
Other debt securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 60,950 |  |  | 39,996 |  |  |  |
Available for sale securities | 473 |  |  | 473 |  |  |  |
Fair Value, Recurring [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 5,212,791 |  |  | 5,193,505 |  |  |  |
Available for sale securities | 12,793,784 |  |  | 12,286,681 |  |  |  |
Residential mortgage loans held for sale | 107,465 | [1] |  | 56,935 | [2] |  |  |
Mortgage servicing rights | 333,246 | [3] |  | 293,884 | [4] |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 225,076 | [5] |  | 410,304 | [6] |  |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 287,509 | [5] |  | 587,473 | [6] |  |  |
Fair Value, Recurring [Member] | U.S. government securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 71,169 |  |  | 10,959 |  |  |  |
Fair Value, Recurring [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 5,023,892 |  |  | 5,105,137 |  |  |  |
Available for sale securities | 8,108,567 |  |  | 6,834,720 |  |  |  |
Fair value option securities | 19,050 |  |  | 20,671 |  |  |  |
Fair Value, Recurring [Member] | Municipal securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 56,780 |  |  | 37,413 |  |  |  |
Available for sale securities | 278,043 |  |  | 502,833 |  |  |  |
Fair Value, Recurring [Member] | Other trading securities |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 60,950 |  |  | 39,996 |  |  |  |
Fair Value, Recurring [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 923 |  |  | 925 |  |  |  |
Fair Value, Recurring [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 828,049 |  |  | 799,877 |  |  |  |
Fair Value, Recurring [Member] | Commercial agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 3,577,729 |  |  | 4,147,853 |  |  |  |
Fair Value, Recurring [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 473 |  |  | 473 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 69,955 |  |  | 9,017 |  |  |  |
Available for sale securities | 923 |  |  | 925 |  |  |  |
Residential mortgage loans held for sale | 0 | [1] |  | 0 | [2] |  |  |
Mortgage servicing rights | 0 | [3] |  | 0 | [4] |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 3,699 | [5] |  | 0 | [6] |  |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 658 | [5] |  | 2,607 | [6] |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. government securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 69,955 |  |  | 9,017 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair value option securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other trading securities |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 923 |  |  | 925 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 5,142,836 |  |  | 5,184,488 |  |  |  |
Available for sale securities | 12,792,388 |  |  | 12,285,283 |  |  |  |
Residential mortgage loans held for sale | 100,364 | [1] |  | 49,749 | [2] |  |  |
Mortgage servicing rights | 0 | [3] |  | 0 | [4] |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 221,377 | [5] |  | 410,304 | [6] |  |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 286,851 | [5] |  | 584,866 | [6] |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. government securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 1,214 |  |  | 1,942 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 5,023,892 |  |  | 5,105,137 |  |  |  |
Available for sale securities | 8,108,567 |  |  | 6,834,720 |  |  |  |
Fair value option securities | 19,050 |  |  | 20,671 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 56,780 |  |  | 37,413 |  |  |  |
Available for sale securities | 278,043 |  |  | 502,833 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other trading securities |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 60,950 |  |  | 39,996 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 828,049 |  |  | 799,877 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 3,577,729 |  |  | 4,147,853 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Available for sale securities | 473 |  |  | 473 |  |  |  |
Residential mortgage loans held for sale | 7,101 | [1] |  | 7,186 | [2] |  |  |
Mortgage servicing rights | 333,246 | [3] |  | 293,884 | [4] |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | $ 0 | [5] |  | $ 0 | [6] |  |  |
Liquidity Discount on Mortgage Loans Qualifying for Sale to US Govt Agencies | 79.41% |  |  | 77.74% |  |  |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | $ 0 | [5] |  | $ 0 | [6] |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. government securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair value option securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Available for sale securities |  |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other trading securities |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial agency mortgage-backed securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  |  |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |
Available for sale securities | $ 473 |  |  | $ 473 |  |  |  |
[1] | Residential mortgage loans held for sale measured at fair value on a recurring basis using significant unobservable inputs (Level 3) consist of residential mortgage loans intended for sale to U.S. government agencies that fail to meet conforming standards and are valued at 79.41% of the unpaid principal balance.
[2] | Residential mortgage loans held for sale measured at fair value on a recurring basis using significant unobservable inputs (Level 3) consist of residential mortgage loans intended for sale to U.S. government agencies that fail to meet conforming standards and are valued at 77.74% of the unpaid principal balance.
[3] | A reconciliation of the beginning and ending fair value of mortgage servicing rights and disclosures of significant assumptions used to determine fair value are presented in Note 5, Mortgage Banking Activities.
[4] | A reconciliation of the beginning and ending fair value of mortgage servicing rights and disclosures of significant assumptions used to determine fair value are presented in Note 5, Mortgage Banking Activities.
[5] | See Note 3 for detail of fair value of derivative contracts by contract type. Derivative contracts in asset and liability positions that were valued based on quoted prices in active markets for identical instruments (Level 1) are primarily exchange-traded interest rate derivative contracts held for trading purposes.
[6] | See Note 3 for detail of fair value of derivative contracts by contract type. Derivative contracts in asset and liability positions that were valued based on quoted prices in active markets for identical instruments (Level 1) are primarily exchange-traded interest rate derivative contracts held for trading purposes.

X
- Definition Fair value option securities represent securities the Company has elected to carry at fair value and separately identified on the balance sheet with changes in fair value recognized in earnings as they occur. Certain residential mortgage-backed securities issued by US government agencies are held as an economic hedge of changes in the fair value of mortgage servicing rights and related derivative contracts. In addition, other securities may be held to manage interest rate risk or for deferred compensation purposes. Securities held for interest rate risk management may be economically hedged by derivative contracts not designated as hedging instruments effectively modify these fixed rate securities into variable rate securities. + References No definition available. + Details
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X
- Definition Represents a liquidity discount applied to the market value of mortgage loans qualifying for sale to U.S. government agencies when a mortgage loan is ineligible for sale to U.S. government agencies. + References No definition available. + Details
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X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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X
- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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