Estimated Fair Values (Estimated Fair Values For Certain Financial Assets And Financial Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	$ 337,814	$ 362,048
Overnight investments	9,114,660	4,347,336
Investment securities available for sale	9,203,427	7,014,243
Investment securities held to maturity	3,809,453	2,816,982
Investment in marketable equity securities	97,528	91,680
Loans held for sale	98,700	124,800
Net loans and leases	32,193,029	32,567,661
Income earned not collected	134,237	145,694
Deposits	51,406,094	43,431,609
Time Deposits	2,480,967	2,889,013
Securities Sold under Agreements to Repurchase	589,101	641,487
Subordinated Debt	477,564	504,518
Other Borrowings	72,155	88,470
FDIC shared-loss payable	0	15,601	$ 112,395
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	337,814	362,048
Overnight investments	9,114,660	4,347,336
Investment securities available for sale	9,203,427	7,014,243
Investment securities held to maturity	3,809,453	2,816,982
Investment in marketable equity securities	97,528	91,680
Loans held for sale	98,741	124,837
Net loans and leases	32,193,029	32,567,661
Income earned not collected	134,237	145,694
Federal Home Loan Bank stock	40,450	45,392
Mortgage servicing assets	23,797	19,628
Deposits	48,925,127	40,542,596
Time Deposits	2,480,967	2,889,013
Securities Sold under Agreements to Repurchase	589,101	641,487
Federal Home Loan Bank Advances	644,659	655,175
Subordinated Debt	477,564	504,518
Other Borrowings	72,155	88,470
FDIC shared-loss payable	0	15,601
Accrued interest payable	7,922	9,414
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	337,814	362,048
Overnight investments	9,114,660	4,347,336
Investment securities available for sale	9,203,427	7,014,243
Investment securities held to maturity	3,759,650	2,838,499
Investment in marketable equity securities	97,528	91,680
Loans held for sale	98,741	124,837
Net loans and leases	31,889,594	33,298,166
Income earned not collected	134,237	145,694
Federal Home Loan Bank stock	40,450	45,392
Mortgage servicing assets	23,784	20,283
Deposits	48,925,127	40,542,596
Time Deposits	2,471,116	2,905,577
Securities Sold under Agreements to Repurchase	589,101	641,487
Federal Home Loan Bank Advances	654,694	677,579
Subordinated Debt	495,483	525,610
Other Borrowings	72,476	89,263
FDIC shared-loss payable	0	15,843
Accrued interest payable	$ 7,922	$ 9,414

Payable to FDIC for Loss Share Agreements

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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