Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Fair Value Assets And Liabilities Measured On A Recurring Basis [Table Text Block]

The fair value of financial assets and liabilities that are measured on a recurring basis is as follows as of December 31, 2022 (in thousands):

	Total		Quoted Prices in Active Markets for Identical Instruments		Significant Other Observable Inputs		Significant Unobservable Inputs
Assets:
Trading securities:
U.S. government securities	$	9,823	$	4,970	$	4,853	$	—
Residential agency mortgage-backed securities	4,406,848		—		4,406,848		—
Municipal securities	21,484		—		21,484		—
Other trading securities	26,006		—		26,006		—
Total trading securities	4,464,161		4,970		4,459,191		—
Available for sale securities:
U.S. Treasury	898		898		—		—
Municipal securities	624,500		—		624,500		—
Residential agency mortgage-backed securities	5,814,496		—		5,814,496		—
Residential non-agency mortgage-backed securities	577,576		—		577,576		—
Commercial agency mortgage-backed securities	4,475,917		—		4,475,917		—
Other debt securities	473		—		—		473
Total available for sale securities	11,493,860		898		11,492,489		473
Fair value option securities — Residential agency mortgage-backed securities	296,590		—		296,590		—
Residential mortgage loans held for sale1	75,272		—		68,054		7,218
Mortgage servicing rights, net2	277,608		—		—		277,608
Derivative contracts, net of cash margin3	880,343		2,110		878,233		—
Liabilities:
Derivative contracts, net of cash margin3	554,900		16		554,884		—

1Residential 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 77.55% of the unpaid principal balance.

2A 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 7, Mortgage Banking Activities.

3See 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.

The fair value of financial assets and liabilities that are measured on a recurring basis is as follows as of December 31, 2021 (in thousands):

	Total		Quoted Prices in Active Markets for Identical Instruments		Significant Other Observable Inputs		Significant Unobservable Inputs
Assets:
Trading securities:
U.S. government securities	$	23,610	$	4,999	$	18,611	$	—
Residential agency mortgage-backed securities	9,068,900		—		9,068,900		—
Municipal securities	25,783		—		25,783		—
Other trading securities	18,520		—		18,520		—
Total trading securities	9,136,813		4,999		9,131,814		—
Available for sale securities:
U.S. Treasury	1,000		1,000		—		—
Municipal securities	508,365		—		508,365		—
Residential agency mortgage-backed securities	8,006,616		—		8,006,616		—
Residential non-agency mortgage-backed securities	24,339		—		24,339		—
Commercial agency mortgage-backed securities	4,617,025		—		4,617,025		—
Other debt securities	472		—		—		472
Total available for sale securities	13,157,817		1,000		13,156,345		472
Fair value option securities — Residential agency mortgage-backed securities	43,770		—		43,770		—
Residential mortgage loans held for sale1	192,295		—		185,969		6,326
Mortgage servicing rights, net2	163,198		—		—		163,198
Derivative contracts, net of cash margin3	1,097,297		8,331		1,088,966		—
Liabilities:
Derivative contracts, net of cash margin3	275,625		—		275,625		—

1Residential 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 95.07% of the unpaid principal balance.

2A 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 7, Mortgage Banking Activities.

3See Note 3 for detail of fair value of derivative contracts by contract type. Derivative contracts based on quoted prices in active markets for identical instruments (Level 1) are exchange-traded interest rate derivative contracts, net of cash margin. Derivative contracts in liability positions that were valued using quoted prices in active markets for identical instruments (Level 1) are exchange-traded energy derivative contracts, fully offset by cash margin.

Fair Value Assets Measured on Nonrecurring Basis [Table Text Block]

The following represents the carrying value of assets measured at fair value on a non-recurring basis and related losses recorded during the year. The carrying value represents only those assets with the balance sheet date for which the fair value was adjusted during the year:

	Carrying Value at December 31, 2022						Fair Value Adjustments for the Year Ended December 31, 2022 Recognized In:
	Quoted Prices in Active Markets for Identical Instruments		Significant Other Observable Inputs		Significant Unobservable Inputs		Gross charge-offs against allowance for loan losses		Other gains (losses), net
Nonaccruing loans	$	—	$	57	$	4,998	$	16,399	$	—
Real estate and other repossessed assets	—		3,873		1,699		—		(6,437)

	Carrying Value at December 31, 2021						Fair Value Adjustments for the Year Ended December 31, 2021 Recognized In:
	Quoted Prices in Active Markets for Identical Instruments		Significant Other Observable Inputs		Significant Unobservable Inputs		Gross charge-offs against allowance for loan losses		Other gains (losses), net
Nonaccruing loans	$	—	$	808	$	1,990	$	2,087	$	—
Real estate and other repossessed assets	—		1,706		—		—		(150)

Fair Value Inputs, Fair Value Measured On a Nonrecurring Basis, Quantitative Information [Table Text Block]

A summary of quantitative information about Non-recurring Fair Value Measurements based on Significant Unobservable Inputs (Level 3) as of December 31, 2022 follows (in thousands):

Quantitative Information about Level 3 Non-recurring Fair Value Measurements
	Fair Value		Valuation Technique(s)	Significant Unobservable Input	Range (Weighted Average)
Nonaccruing loans	$	4,998	Discounted cash flows	Management knowledge of industry and non-real estate collateral including but not limited to recoverable oil & gas reserves, forward looking commodity prices, and estimated operating costs	9% - 24% (23%)1
Real estate and other repossessed assets	1,699		Discounted cash flows	Management knowledge of industry and non-real estate collateral including but not limited to recoverable oil & gas reserves, forward looking commodity prices, and estimated operating costs	N/A

1    Represents fair value as a percentage of the unpaid principal balance.

A summary of quantitative information about Non-recurring Fair Value Measurements based on Significant Unobservable Inputs (Level 3) as of December 31, 2021 follows (in thousands):

Quantitative Information about Level 3 Non-recurring Fair Value Measurements
	Fair Value		Valuation Technique(s)	Significant Unobservable Input	Range (Weighted Average)
Nonaccruing loans	$	1,990	Discounted cash flows	Management knowledge of industry and non-real estate collateral including but not limited to recoverable oil & gas reserves, forward looking commodity prices, and estimated operating costs	16% - 97% (37%)1

1    Represents fair value as a percentage of the unpaid principal balance.

Fair Value of Financial Instruments [Table Text Block]

The following table presents the carrying values and estimated fair values of all financial instruments, including those financial assets and liabilities that are not measured and reported at fair value on a recurring basis or are measured at fair value on a non-recurring basis (dollars in thousands):

	December 31, 2022
	Carrying Value		Estimated Fair Value		Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash and due from banks	$	943,810	$	943,810	$	943,810	$	—	$	—
Interest-bearing cash and cash equivalents	457,906		457,906		457,906		—		—
Trading securities:
U.S. government securities	9,823		9,823		4,970		4,853		—
Residential agency mortgage-backed securities	4,406,848		4,406,848		—		4,406,848		—
Municipal securities	21,484		21,484		—		21,484		—
Other trading securities	26,006		26,006		—		26,006		—
Total trading securities	4,464,161		4,464,161		4,970		4,459,191		—
Investment securities:
Municipal securities	170,629		176,621		—		38,106		138,515
Residential agency mortgage-backed securities	2,315,219		2,143,360		—		2,143,360		—
Commercial agency mortgage-backed securities	15,609		14,588		—		14,588		—
Other debt securities	12,788		12,199		—		12,199		—
Total investment securities	2,514,245		2,346,768		—		2,208,253		138,515
Allowance for credit losses	(558)		—		—		—		—
Investment securities, net of allowance	2,513,687		2,346,768		—		2,208,253		138,515
Available for sale securities:
U.S. Treasury	898		898		898		—		—
Municipal securities	624,500		624,500		—		624,500		—
Residential agency mortgage-backed securities	5,814,496		5,814,496		—		5,814,496		—
Residential non-agency mortgage-backed securities	577,576		577,576		—		577,576		—
Commercial agency mortgage-backed securities	4,475,917		4,475,917		—		4,475,917		—
Other debt securities	473		473		—		—		473
Total available for sale securities	11,493,860		11,493,860		898		11,492,489		473
Fair value option securities — Residential agency mortgage-backed securities	296,590		296,590		—		296,590		—
Residential mortgage loans held for sale	75,272		75,272		—		68,054		7,218
Loans:
Commercial	14,198,187		13,891,453		—		—		13,891,453
Commercial real estate	4,606,777		4,454,048		—		—		4,454,048
Paycheck protection program	14,312		14,312		—		—		14,312
Loans to individuals	3,737,874		3,531,410		—		—		3,531,410
Total loans	22,557,150		21,891,223		—		—		21,891,223
Allowance for loan losses	(235,704)		—		—		—		—
Loans, net of allowance	22,321,446		21,891,223		—		—		21,891,223
Mortgage servicing rights	277,608		277,608		—		—		277,608
Derivative instruments with positive fair value, net of cash margin	880,343		880,343		2,110		878,233		—
Deposits with no stated maturity	33,018,863		33,018,863		—		—		33,018,863
Time deposits	1,461,842		1,431,245		—		—		1,431,245
Other borrowed funds	7,007,285		7,005,305		—		—		7,005,305
Subordinated debentures	131,205		121,497		—		121,497		—
Derivative instruments with negative fair value, net of cash margin	554,900		554,900		16		554,884		—

	December 31, 2021
	Carrying Value		Estimated Fair Value		Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash and due from banks	$	712,067	$	712,067	$	712,067	$	—	$	—
Interest-bearing cash and cash equivalents	2,125,343		2,125,343		2,125,343		—		—
Trading securities:
U.S. government securities	23,610		23,610		4,999		18,611		—
Residential agency mortgage-backed securities	9,068,900		9,068,900		—		9,068,900		—
Municipal securities	25,783		25,783		—		25,783		—
Other trading securities	18,520		18,520		—		18,520		—
Total trading securities	9,136,813		9,136,813		4,999		9,131,814		—
Investment securities:
Municipal securities	203,772		223,609		—		57,698		165,911
Residential agency mortgage-backed securities	6,939		7,500		—		7,500		—
Other debt securities	288		286		—		286		—
Total investment securities	210,999		231,395		—		65,484		165,911
Allowance for credit losses	(555)		—		—		—		—
Investment securities, net of allowance	210,444		231,395		—		65,484		165,911
Available for sale securities:
U.S. Treasury securities	1,000		1,000		1,000		—		—
Municipal securities	508,365		508,365		—		508,365		—
Residential agency mortgage-backed securities	8,006,616		8,006,616		—		8,006,616		—
Residential non-agency mortgage-backed securities	24,339		24,339		—		24,339		—
Commercial agency mortgage-backed securities	4,617,025		4,617,025		—		4,617,025		—
Other debt securities	472		472		—		—		472
Total available for sale securities	13,157,817		13,157,817		1,000		13,156,345		472
Fair value option securities — Residential agency mortgage-backed securities	43,770		43,770		—		43,770		—
Residential mortgage loans held for sale	192,295		192,295		—		185,969		6,326
Loans:
Commercial	12,506,465		12,395,664		—		—		12,395,664
Commercial real estate	3,831,325		3,786,767		—		—		3,786,767
Paycheck protection program	276,341		269,912		—		—		269,912
Loans to individuals	3,591,549		3,586,878		—		—		3,586,878
Total loans	20,205,680		20,039,221		—		—		20,039,221
Allowance for loan losses	(256,421)		—		—		—		—
Loans, net of allowance	19,949,259		20,039,221		—		—		20,039,221
Mortgage servicing rights	163,198		163,198		—		—		163,198
Derivative instruments with positive fair value, net of cash margin	1,097,297		1,097,297		8,331		1,088,966		—
Deposits with no stated maturity	39,537,731		39,537,731		—		—		39,537,731
Time deposits	1,704,328		1,703,886		—		—		1,703,886
Other borrowed funds	2,363,202		2,360,746		—		—		2,360,746
Subordinated debentures	131,226		141,761		—		141,761		—
Derivative instruments with negative fair value, net of cash margin	275,625		275,625		—		275,625		—