Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Financial Assets and Financial Liabilities Measured at Fair Value on Recurring Basis

The tables below summarize financial assets and financial liabilities measured at fair value on a recurring basis as of June 30, 2023 and December 31, 2022, segregated by the level of the valuation inputs within the fair value hierarchy of ASC Topic 820 utilized to measure fair value.

	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
June 30, 2023
Securities available for sale:
U.S. Treasury	$	5,072,888	$	—	$	—	$	5,072,888
Residential mortgage-backed securities	—		6,792,775		—		6,792,775
States and political subdivisions	—		5,341,016		—		5,341,016
Other	—		42,578		—		42,578
Trading account securities:
U.S. Treasury	27,546		—		—		27,546
States and political subdivisions	—		4,971		—		4,971
Derivative assets:
Interest rate swaps, caps and floors	—		94,362		—		94,362
Commodity swaps and options	—		65,814		—		65,814
Derivative liabilities:
Interest rate swaps, caps and floors	—		94,291		—		94,291
Commodity swaps and options	—		64,802		—		64,802
December 31, 2022
Securities available for sale:
U.S. Treasury	$	5,051,587	$	—	$	—	$	5,051,587
Residential mortgage-backed securities	—		6,376,236		—		6,376,236
States and political subdivisions	—		6,773,355		—		6,773,355
Other	—		42,427		—		42,427
Trading account securities:
U.S. Treasury	25,879		—		—		25,879
States and political subdivisions	—		2,166		—		2,166
Derivative assets:
Interest rate swaps, caps and floors	—		86,793		—		86,793
Commodity swaps and options	—		106,685		—		106,685
Foreign currency forward contracts	11		—		—		11
Derivative liabilities:
Interest rate swaps, caps and floors	—		95,533		—		95,533
Commodity swaps and options	—		105,392		—		105,392
Foreign currency forward contracts	11		—		—		11

Impaired Loans Remeasured And Reported At Fair Value Specific Valuation Allowance Allocation Method Of Underlying Collateral [Table Text Block]

The following table presents collateral dependent loans that were remeasured and reported at fair value through a specific allocation of the allowance for credit losses on loans based upon the fair value of the underlying collateral during the reported periods.

	Six Months Ended June 30, 2023				Six Months Ended June 30, 2022
	Level 2		Level 3		Level 2		Level 3
Carrying value before allocations	$	19,064	$	20,171	$	5,454	$	3,614
Specific (allocations) reversals of prior allocations	(1,300)		(2,100)		(1,327)		6,877
Fair value	$	17,764	$	18,071	$	4,127	$	10,491

Estimated Fair Values of Financial Instruments

The estimated fair values of financial instruments that are reported at amortized cost in our consolidated balance sheets, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows:

	June 30, 2023				December 31, 2022
	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Financial assets:
Level 2 inputs:
Cash and cash equivalents	$	7,107,336	$	7,107,336	$	12,028,132	$	12,028,132
Securities held to maturity	3,691,220		3,543,929		2,639,083		2,467,865
Cash surrender value of life insurance policies	190,575		190,575		190,188		190,188
Accrued interest receivable	236,967		236,967		243,682		243,682
Level 3 inputs:
Loans, net	17,512,692		16,933,702		16,927,348		16,343,417
Financial liabilities:
Level 2 inputs:
Deposits	40,700,830		40,683,556		43,954,196		43,920,741
Federal funds purchased	13,525		13,525		51,650		51,650
Repurchase agreements	3,569,870		3,569,870		4,660,641		4,660,641
Junior subordinated deferrable interest debentures	123,098		123,712		123,069		123,712
Subordinated notes	99,413		94,571		99,335		97,014
Accrued interest payable	40,523		40,523		18,444		18,444