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Fair Value Measurements, Financial Instruments (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017
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Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | $ 1,900,395 |  | $ 1,956,923 |  |  |
Investment securities | 327,677 |  | 355,187 |  |  |
Available for sale securities | 10,514,414 |  | 8,857,120 |  |  |
Fair value option securities | 1,138,819 |  | 283,235 |  |  |
Residential mortgage loans held for sale | 193,570 |  | 149,221 |  |  |
Loans | 22,255,652 |  | 21,656,730 |  |  |
Allowance for loan losses | (202,534) | $ (205,340) | (207,457) | $ (215,142) | $ (223,967) | $ (230,682)
Loans, net of allowance | 22,053,118 |  | 21,449,273 |  |  |
Mortgage servicing rights | 208,308 | 238,193 | 259,254 | 278,719 | 274,978 | 252,867
Derviative contracts, net of cash collateral, Assets, Fair value | 415,221 |  | 320,929 |  |  |
Time deposits | 2,227,938 |  | 2,113,380 |  |  |
Subordinated debentures | 275,892 |  | 275,913 |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 381,454 |  | 362,306 |  |  |
Commercial [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 14,336,908 |  | 13,636,078 |  |  |
Allowance for loan losses | (106,397) | (103,577) | (102,226) | (113,722) | (120,083) | (124,269)
Commercial real estate [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 4,710,033 |  | 4,764,813 |  |  |
Allowance for loan losses | (54,188) | (58,134) | (60,026) | (58,758) | (57,070) | (56,621)
Residential mortgage [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 2,170,822 |  | 2,230,033 |  |  |
Allowance for loan losses | (15,724) | (15,668) | (17,964) | (18,544) | (18,431) | (18,451)
Personal [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 1,037,889 |  | 1,025,806 |  |  |
Allowance for loan losses | (9,388) | $ (8,783) | (9,473) | $ (8,646) | $ (8,408) | $ (9,124)
U.S. government agency debentures [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 83,148 |  | 63,765 |  |  |
Residential agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 1,620,613 |  | 1,791,584 |  |  |
Investment securities | 11,599 |  | 12,612 |  |  |
Available for sale securities | 7,354,741 |  | 5,804,708 |  |  |
Municipal and other tax-exempt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 49,718 |  | 34,507 |  |  |
Investment securities | 124,822 |  | 137,296 |  |  |
Available for sale securities | 2,470 |  | 2,864 |  |  |
U.S. Treasury [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 1,889 |  | 493 |  |  |
Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 47,057 |  | 59,736 |  |  |
Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 3,107,785 |  | 2,953,889 |  |  |
Other debt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 53,370 |  | 24,411 |  |  |
Investment securities | 191,256 |  | 205,279 |  |  |
Available for sale securities | 472 |  | 35,430 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Cash and due from banks | 739,109 |  | 741,749 |  |  |
Interest-bearing cash and cash equivalents | 596,382 |  | 401,675 |  |  |
Trading securities | 1,900,395 |  | 1,956,923 |  |  |
Investment securities | 327,677 |  | 355,187 |  |  |
Available for sale securities | 10,514,414 |  | 8,857,120 |  |  |
Residential mortgage loans held for sale | 193,570 |  | 149,221 |  |  |
Loans | 22,255,652 |  | 21,656,730 |  |  |
Allowance for loan losses | (202,534) |  | (207,457) |  |  |
Loans, net of allowance | 22,053,118 |  | 21,449,273 |  |  |
Mortgage servicing rights | 208,308 |  | 259,254 |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 415,221 |  | 320,929 |  |  |
Deposits with no stated maturity | 23,077,183 |  | 23,150,383 |  |  |
Time deposits | 2,227,938 |  | 2,113,380 |  |  |
Other borrowed funds | 10,155,756 |  | 8,161,211 |  |  |
Subordinated debentures | 275,892 |  | 275,913 |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 381,454 |  | 362,306 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Commercial [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 14,336,908 |  | 13,636,078 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Commercial real estate [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 4,710,033 |  | 4,764,813 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Residential mortgage [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 2,170,822 |  | 2,230,033 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Personal [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 1,037,889 |  | 1,025,806 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 83,148 |  | 63,765 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 1,620,613 |  | 1,791,584 |  |  |
Investment securities | 11,599 |  | 12,612 |  |  |
Available for sale securities | 7,354,741 |  | 5,804,708 |  |  |
Fair value option securities | 1,138,820 |  | 283,235 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 49,718 |  | 34,507 |  |  |
Investment securities | 124,822 |  | 137,296 |  |  |
Available for sale securities | 2,470 |  | 2,864 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Asset-backed securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 93,546 |  | 42,656 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Other trading securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 53,370 |  | 24,411 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | U.S. Treasury [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 1,889 |  | 493 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 47,057 |  | 59,736 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 3,107,785 |  | 2,953,889 |  |  |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Other debt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Investment securities | 191,256 |  | 205,279 |  |  |
Available for sale securities | 472 |  | 35,430 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Cash and due from banks | 739,109 |  | 741,749 |  |  |
Interest-bearing cash and cash equivalents | 596,382 |  | 401,675 |  |  |
Trading securities | 1,900,395 |  | 1,956,923 |  |  |
Investment securities | 347,015 |  | 367,298 |  |  |
Available for sale securities | 10,514,414 |  | 8,857,120 |  |  |
Residential mortgage loans held for sale | 193,570 |  | 149,221 |  |  |
Loans | 22,204,975 |  | 21,478,228 |  |  |
Allowance for loan losses | 0 |  | 0 |  |  |
Loans, net of allowance | 22,204,975 |  | 21,478,228 |  |  |
Mortgage servicing rights | 208,308 |  | 259,254 |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 415,221 |  | 320,929 |  |  |
Deposits with no stated maturity | 23,077,183 |  | 23,150,383 |  |  |
Time deposits | 2,220,527 |  | 2,073,538 |  |  |
Other borrowed funds | 10,115,711 |  | 7,071,953 |  |  |
Subordinated debentures | 274,697 |  | 261,977 |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 381,454 |  | 362,306 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 14,282,197 |  | 13,526,162 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 4,703,587 |  | 4,713,747 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 2,190,665 |  | 2,213,951 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 1,028,526 |  | 1,024,368 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 83,148 |  | 63,765 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 1,620,613 |  | 1,791,584 |  |  |
Investment securities | 12,099 |  | 12,770 |  |  |
Available for sale securities | 7,354,741 |  | 5,804,708 |  |  |
Fair value option securities | 1,138,820 |  | 283,235 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 49,718 |  | 34,507 |  |  |
Investment securities | 128,009 |  | 138,562 |  |  |
Available for sale securities | 2,470 |  | 2,864 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 93,546 |  | 42,656 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 53,370 |  | 24,411 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 1,889 |  | 493 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 47,057 |  | 59,736 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 3,107,785 |  | 2,953,889 |  |  |
Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Investment securities | 206,907 |  | 215,966 |  |  |
Available for sale securities | 472 |  | 35,430 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Cash and due from banks | 739,109 |  | 741,749 |  |  |
Interest-bearing cash and cash equivalents | 596,382 |  | 401,675 |  |  |
Trading securities | 0 |  | 0 |  |  |
Investment securities | 0 |  | 0 |  |  |
Available for sale securities | 1,889 |  | 493 |  |  |
Residential mortgage loans held for sale | 0 |  | 0 |  |  |
Loans | 0 |  | 0 |  |  |
Allowance for loan losses | 0 |  | 0 |  |  |
Loans, net of allowance | 0 |  | 0 |  |  |
Mortgage servicing rights | 0 |  | 0 |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 29,352 |  | 44,074 |  |  |
Deposits with no stated maturity | 0 |  | 0 |  |  |
Time deposits | 0 |  | 0 |  |  |
Other borrowed funds | 0 |  | 0 |  |  |
Subordinated debentures | 0 |  | 0 |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Investment securities | 0 |  | 0 |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair value option securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Investment securities | 0 |  | 0 |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 1,889 |  | 493 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Investment securities | 0 |  | 0 |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Cash and due from banks | 0 |  | 0 |  |  |
Interest-bearing cash and cash equivalents | 0 |  | 0 |  |  |
Trading securities | 1,900,395 |  | 1,956,923 |  |  |
Investment securities | 148,305 |  | 159,237 |  |  |
Available for sale securities | 10,512,053 |  | 8,856,155 |  |  |
Residential mortgage loans held for sale | 177,497 |  | 134,014 |  |  |
Loans | 0 |  | 0 |  |  |
Allowance for loan losses | 0 |  | 0 |  |  |
Loans, net of allowance | 0 |  | 0 |  |  |
Mortgage servicing rights | 0 |  | 0 |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 385,869 |  | 276,855 |  |  |
Deposits with no stated maturity | 0 |  | 0 |  |  |
Time deposits | 0 |  | 0 |  |  |
Other borrowed funds | 0 |  | 0 |  |  |
Subordinated debentures | 274,697 |  | 261,977 |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 381,454 |  | 362,306 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 83,148 |  | 63,765 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 1,620,613 |  | 1,791,584 |  |  |
Investment securities | 12,099 |  | 12,770 |  |  |
Available for sale securities | 7,354,741 |  | 5,804,708 |  |  |
Fair value option securities | 1,138,820 |  | 283,235 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 49,718 |  | 34,507 |  |  |
Investment securities | 128,009 |  | 138,562 |  |  |
Available for sale securities | 2,470 |  | 2,864 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 93,546 |  | 42,656 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 53,370 |  | 24,411 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 47,057 |  | 59,736 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 3,107,785 |  | 2,953,889 |  |  |
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Investment securities | 8,197 |  | 7,905 |  |  |
Available for sale securities | 0 |  | 34,958 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Cash and due from banks | 0 |  | 0 |  |  |
Interest-bearing cash and cash equivalents | 0 |  | 0 |  |  |
Trading securities | 0 |  | 0 |  |  |
Investment securities | 198,710 |  | 208,061 |  |  |
Available for sale securities | 472 |  | 472 |  |  |
Residential mortgage loans held for sale | 16,073 |  | 15,207 |  |  |
Loans | 22,204,975 |  | 21,478,228 |  |  |
Allowance for loan losses | 0 |  | 0 |  |  |
Loans, net of allowance | 22,204,975 |  | 21,478,228 |  |  |
Mortgage servicing rights | 208,308 |  | 259,254 |  |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 0 |  | 0 |  |  |
Deposits with no stated maturity | 23,077,183 |  | 23,150,383 |  |  |
Time deposits | 2,220,527 |  | 2,073,538 |  |  |
Other borrowed funds | 10,115,711 |  | 7,071,953 |  |  |
Subordinated debentures | 0 |  | 0 |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 14,282,197 |  | 13,526,162 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 4,703,587 |  | 4,713,747 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 2,190,665 |  | 2,213,951 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Loans | 1,028,526 |  | 1,024,368 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Investment securities | 0 |  | 0 |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair value option securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Investment securities | 0 |  | 0 |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Trading securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Available for sale securities | 0 |  | 0 |  |  |
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member] |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |
Investment securities | 198,710 |  | 208,061 |  |  |
Available for sale securities | $ 472 |  | $ 472 |  |  |

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. May be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. May be used in both the balance sheet and disclosure in the same submission. Represents time deposits with no stated maturity as presented on the statement of financial position. + References No definition available. + Details
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- 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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- Definition Represents money market or interest-bearing cash accounts held in other financial institutions (including the Federal Reserve); federal funds sold to other depository institutions, securities brokers or securities dealers and securities purchased under agreements to resell. + References No definition available. + Details
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- 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 -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- 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. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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- Definition Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
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- Definition Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746 + Details
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