Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2022

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, 2022 and December 31, 2021, 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, 2022
Securities available for sale:
U.S. Treasury	$	4,416,299	$	—	$	—	$	4,416,299
Residential mortgage-backed securities	—		5,335,725		—		5,335,725
States and political subdivisions	—		6,987,296		—		6,987,296
Other	—		42,365		—		42,365
Trading account securities:
U.S. Treasury	24,615		—		—		24,615
States and political subdivisions	—		65		—		65
Derivative assets:
Interest rate swaps, caps and floors	—		41,485		—		41,485
Commodity swaps and options	—		245,218		—		245,218
Foreign currency forward contracts	199		—		—		199
Derivative liabilities:
Interest rate swaps, caps and floors	—		58,240		—		58,240
Commodity swaps and options	—		243,638		—		243,638
Foreign currency forward contracts	195		—		—		195
December 31, 2021
Securities available for sale:
U.S. Treasury	$	2,179,433	$	—	$	—	$	2,179,433
Residential mortgage-backed securities	—		4,066,265		—		4,066,265
States and political subdivisions	—		7,636,571		—		7,636,571
Other	—		42,359		—		42,359
Trading account securities:
U.S. Treasury	24,237		—		—		24,237
States and political subdivisions	—		925		—		925
Derivative assets:
Interest rate swaps, caps and floors	—		44,310		—		44,310
Commodity swaps and options	—		114,757		—		114,757
Foreign currency forward contracts	33		—		—		33
Derivative liabilities:
Interest rate swaps, caps and floors	—		25,261		—		25,261
Commodity swaps and options	—		113,261		—		113,261
Foreign currency forward contracts	55		—		—		55

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, 2022				Six Months Ended June 30, 2021
	Level 2		Level 3		Level 2		Level 3
Carrying value before allocations	$	5,454	$	3,614	$	3,399	$	19,423
Specific (allocations) reversals of prior allocations	(1,327)		6,877		(336)		(3,273)
Fair value	$	4,127	$	10,491	$	3,063	$	16,150

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, 2022				December 31, 2021
	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Financial assets:
Level 2 inputs:
Cash and cash equivalents	$	13,658,585	$	13,658,585	$	16,583,000	$	16,583,000
Securities held to maturity	1,946,428		1,828,515		1,749,179		1,809,143
Cash surrender value of life insurance policies	189,823		189,823		190,139		190,139
Accrued interest receivable	194,049		194,049		179,111		179,111
Level 3 inputs:
Loans, net	16,496,394		16,126,497		16,087,731		16,079,454
Financial liabilities:
Level 2 inputs:
Deposits	45,601,765		45,584,113		42,695,696		41,343,426
Federal funds purchased	43,200		43,200		25,925		25,925
Repurchase agreements	1,664,685		1,664,685		2,740,799		2,740,799
Junior subordinated deferrable interest debentures	123,040		123,712		123,011		123,712
Subordinated notes	99,256		99,626		99,178		111,430
Accrued interest payable	6,059		6,059		3,026		3,026