Loans (Tables)

9 Months Ended

Sep. 30, 2020

Receivables [Abstract]

Loans

Loans were as follows:

	September 30, 2020		Percentage of Total		December 31, 2019		Percentage of Total
Commercial and industrial	$	4,820,018	26.4	%	$	5,187,466	35.2	%
Energy:
Production	1,108,753		6.1		1,348,900		9.2
Service	163,197		0.9		192,996		1.3
Other	91,418		0.4		110,986		0.8
Total energy	1,363,368		7.4		1,652,882		11.2
Paycheck Protection Program	3,226,980		17.7		—		—
Commercial real estate:
Commercial mortgages	5,412,731		29.7		4,594,113		31.1
Construction	1,274,080		7.0		1,312,659		8.9
Land	320,407		1.8		289,467		2.0
Total commercial real estate	7,007,218		38.5		6,196,239		42.0
Consumer real estate:
Home equity loans	340,226		1.9		375,596		2.6
Home equity lines of credit	434,171		2.4		354,671		2.4
Other	533,356		2.9		464,146		3.1
Total consumer real estate	1,307,753		7.2		1,194,413		8.1
Total real estate	8,314,971		45.7		7,390,652		50.1
Consumer and other	498,540		2.8		519,332		3.5
Total loans	$	18,223,877	100.0	%	$	14,750,332	100.0	%

Non-Accrual Loans, Segregated by Class of Loans

Non-accrual loans, segregated by class of loans, were as follows:

	September 30, 2020				December 31, 2019
	Total Non-Accrual		Non-Accrual with No Credit Loss Allowance		Total Non-Accrual		Non-Accrual with No Credit Loss Allowance
Commercial and industrial	$	21,566	$	6,583	$	26,038	$	13,266
Energy	54,041		33,324		65,761		3,281
Paycheck Protection Program	—		—		—		—
Commercial real estate:
Buildings, land and other	13,525		6,754		8,912		6,558
Construction	680		680		665		665
Consumer real estate	1,748		1,748		922		922
Consumer and other	18		—		5		—
Total	$	91,578	$	49,089	$	102,303	$	24,692

Financing Receivable, Non-Accrual Loans, Segregated by Class of Loan and Year of Origination

The following table presents non-accrual loans as of September 30, 2020 by class and year of origination.

	2020		2019		2018		2017		2016		Prior		Revolving Loans		Revolving Loans Converted to Term		Total
Commercial and industrial	$	9,317	$	3,743	$	1,886	$	1,263	$	110	$	51	$	1,879	$	3,317	$	21,566
Energy	24,149		7,021		2,204		—		—		—		15,054		5,613		54,041
Paycheck Protection Program	—		—		—		—		—		—		—		—		—
Commercial real estate:
Buildings, land and other	1,426		6,014		169		1,372		840		3,590		114		—		13,525
Construction	680		—		—		—		—		—		—		—		680
Consumer real estate	—		—		421		211		350		382		261		123		1,748
Consumer and other	—		—		—		—		—		—		18		—		18
Total	$	35,572	$	16,778	$	4,680	$	2,846	$	1,300	$	4,023	$	17,326	$	9,053	$	91,578

Age Analysis of Past Due Loans, Segregated by Class of Loans

An age analysis of past due loans (including both accruing and non-accruing loans), segregated by class of loans, as of September 30, 2020 was as follows:

	Loans 30-89 Days Past Due		Loans 90 or More Days Past Due		Total Past Due Loans		Current Loans		Total Loans		Accruing Loans 90 or More Days Past Due
Commercial and industrial	$	36,067	$	25,115	$	61,182	$	4,758,836	$	4,820,018	$	19,392
Energy	31,071		9,588		40,659		1,322,709		1,363,368		559
Paycheck Protection Program	—		—		—		3,226,980		3,226,980		—
Commercial real estate:
Buildings, land and other	25,113		19,571		44,684		5,688,454		5,733,138		11,676
Construction	—		—		—		1,274,080		1,274,080		—
Consumer real estate	11,054		4,761		15,815		1,291,938		1,307,753		3,406
Consumer and other	6,629		673		7,302		491,238		498,540		673
Total	$	109,934	$	59,708	$	169,642	$	18,054,235	$	18,223,877	$	35,706

Troubled Debt Restructurings

Troubled debt restructurings during the nine months ended September 30, 2020 and September 30, 2019 are set forth in the following table.

	Nine Months Ended September 30, 2020				Nine Months Ended September 30, 2019
	Balance at Restructure		Balance at Period-End		Balance at Restructure		Balance at Period-End
Commercial and industrial	$	3,660	$	1,415	$	3,845	$	2,188
Commercial real estate:
Buildings, land and other	6,606		6,585		9,456		9,494
Construction	1,192		1,181		—		—
Consumer real estate	—		—		124		123
Consumer and other	1,104		104		—		—
	$	12,562	$	9,285	$	13,425	$	11,805

Restructured Loans Past Due in Excess of 90 Days on Financing Receivables

Additional information related to restructured loans as of or for the three months ended September 30, 2020 and September 30, 2019 is set forth in the following table.

	September 30, 2020		September 30, 2019
Restructured loans past due in excess of 90 days at period-end:
Number of loans	2		4
Dollar amount of loans	$	3,682	$	3,244
Restructured loans on non-accrual status at period end	5,353		5,645
Charge-offs of restructured loans:
Recognized in connection with restructuring	—		1,500
Recognized on previously restructured loans	2,188		—

Weighted Average Risk Grades for All Commercial Loans by Class and Year of Origination

The following tables present weighted-average risk grades for all commercial loans, by class and year of origination/renewal as of September 30, 2020. Paycheck Protection Program (“PPP”) loans are excluded as such loans are fully guaranteed by the Small Business Administration (“SBA”).

	2020		2019		2018		2017		2016		Prior		Revolving Loans		Revolving Loans Converted to Term		Total		W/A Risk Grade
Commercial and industrial
Risk grades 1-8	$	1,101,917	$	625,692	$	340,799	$	251,180	$	120,777	$	129,757	$	1,788,761	$	43,468	$	4,402,351	6.12
Risk grade 9	69,846		27,843		36,271		21,352		9,910		1,087		77,802		4,462		248,573		9.00
Risk grade 10	4,394		7,722		13,867		6,875		812		824		60,028		4,347		98,869		10.00
Risk grade 11	3,675		4,507		6,720		4,422		1,896		167		17,909		9,363		48,659		11.00
Risk grade 12	6,917		2,791		1,544		708		110		51		1,350		3,022		16,493		12.00
Risk grade 13	2,400		952		342		555		—		—		529		295		5,073		13.00
	$	1,189,149	$	669,507	$	399,543	$	285,092	$	133,505	$	131,886	$	1,946,379	$	64,957	$	4,820,018	6.42
W/A risk grade	6.12		6.81		7.20		6.32		6.37		5.87		6.32		7.92		6.42
Energy
Risk grades 1-8	$	454,901	$	25,589	$	10,956	$	6,732	$	1,481	$	4,709	$	407,478	$	24,936	$	936,782	6.18
Risk grade 9	108,859		5,542		3,190		—		—		—		90,292		14,974		222,857		9.00
Risk grade 10	486		4,113		1,461		—		907		—		7,837		2,105		16,909		10.00
Risk grade 11	78,832		15,724		3,280		1,210		—		1,066		32,398		269		132,779		11.00
Risk grade 12	24,149		4,829		714		—		—		—		10,629		5,613		45,934		12.00
Risk grade 13	—		2,192		1,490		—		—		—		4,425		—		8,107		13.00
	$	667,227	$	57,989	$	21,091	$	7,942	$	2,388	$	5,775	$	553,059	$	47,897	$	1,363,368	7.39
W/A risk grade	7.43		9.19		8.78		7.83		7.93		8.06		6.98		8.76		7.39

	2020		2019		2018		2017		2016		Prior		Revolving Loans		Revolving Loans Converted to Term		Total		W/A Risk Grade
Commercial real estate:
Buildings, land, other
Risk grades 1-8	$	1,167,872	$	1,010,418	$	829,640	$	660,047	$	430,971	$	752,461	$	62,672	$	53,480	$	4,967,561	6.98
Risk grade 9	26,056		93,113		67,546		66,365		45,477		92,060		4,413		1,042		396,072		9.00
Risk grade 10	1,362		26,080		29,357		39,853		65,702		42,528		4,147		2,876		211,905		10.00
Risk grade 11	7,416		7,108		13,425		42,660		10,487		59,730		3,038		211		144,075		11.00
Risk grade 12	1,226		5,214		169		1,372		840		3,340		51		—		12,212		12.00
Risk grade 13	200		800		—		—		—		250		63		—		1,313		13.00
	$	1,204,132	$	1,142,733	$	940,137	$	810,297	$	553,477	$	950,369	$	74,384	$	57,609	$	5,733,138	7.34
W/A risk grade	7.09		7.34		7.46		7.48		7.73		7.26		7.41		6.84		7.34
Construction
Risk grades 1-8	$	272,025	$	480,166	$	224,389	$	753	$	1,164	$	1,786	$	160,654	$	—	$	1,140,937	7.01
Risk grade 9	31,402		8,370		—		39,688		—		—		14,608		—		94,068		9.00
Risk grade 10	6,133		—		27,479		—		—		—		3,838		—		37,450		10.00
Risk grade 11	—		—		—		—		—		945		—		—		945		11.00
Risk grade 12	680		—		—		—		—		—		—		—		680		12.00
Risk grade 13	—		—		—		—		—		—		—		—		—		13.00
	$	310,240	$	488,536	$	251,868	$	40,441	$	1,164	$	2,731	$	179,100	$	—	$	1,274,080	7.25
W/A risk grade	6.87		7.18		7.74		8.98		7.29		8.02		7.00		—		7.25
Total commercial real estate	$	1,514,372	$	1,631,269	$	1,192,005	$	850,738	$	554,641	$	953,100	$	253,484	$	57,609	$	7,007,218	7.33
W/A risk grade	7.04		7.29		7.52		7.55		7.73		7.26		7.12		6.84		7.33

Weighted Average Risk Grades for All Commercial Loans by Class

The following tables present weighted average risk grades for all commercial loans by class as of December 31, 2019.

	Commercial and Industrial			Energy			Commercial Real Estate - Buildings, Land and Other			Commercial Real Estate - Construction			Total Commercial Real Estate
	W/A Risk Grade	Loans		W/A Risk Grade	Loans		W/A Risk Grade	Loans		W/A Risk Grade	Loans		W/A Risk Grade	Loans
Risk grades 1-8	6.17	$	4,788,857	5.90	$	1,488,301	6.78	$	4,523,271	7.25	$	1,274,098	6.88	$	5,797,369
Risk grade 9	9.00	247,212		9.00	32,163		9.00	163,714		9.00	21,509		9.00	185,223
Risk grade 10	10.00	71,472		10.00	51,898		10.00	103,626		10.00	15,243		10.00	118,869
Risk grade 11	11.00	53,887		11.00	14,760		11.00	84,057		11.00	1,144		11.00	85,201
Risk grade 12	12.00	18,189		12.00	45,514		12.00	8,529		12.00	665		12.00	9,194
Risk grade 13	13.00	7,849		13.00	20,246		13.00	383		13.00	—		13.00	383
Total	6.44	$	5,187,466	6.39	$	1,652,882	7.01	$	4,883,580	7.31	$	1,312,659	7.07	$	6,196,239

Age analysis of Past Due Consumer Loans by Class and Year of Origination

Information about the payment status of consumer loans, segregated by portfolio segment and year of origination, as of September 30, 2020 was as follows:

	2020		2019		2018		2017		2016		Prior		Revolving Loans		Revolving Loans Converted to Term		Total
Consumer real estate:
Past due 30-89 days	$	787	$	850	$	1,434	$	858	$	540	$	4,558	$	1,535	$	492	$	11,054
Past due 90 or more days	—		139		894		542		351		2,028		600		207		4,761
Total past due	787		989		2,328		1,400		891		6,586		2,135		699		15,815
Current loans	253,392		188,770		106,947		93,143		75,216		142,983		414,331		17,156		1,291,938
Total	$	254,179	$	189,759	$	109,275	$	94,543	$	76,107	$	149,569	$	416,466	$	17,855	$	1,307,753
Consumer and other:
Past due 30-89 days	$	1,328	$	326	$	288	$	75	$	2	$	1	$	4,313	$	296	$	6,629
Past due 90 or more days	69		189		3		—		—		1		372		39		673
Total past due	1,397		515		291		75		2		2		4,685		335		7,302
Current loans	38,114		32,214		7,985		3,131		2,070		950		376,762		30,012		491,238
Total	$	39,511	$	32,729	$	8,276	$	3,206	$	2,072	$	952	$	381,447	$	30,347	$	498,540

Revolving Loans Converted to Term [Table Text Block]

Revolving loans that converted to term during the three and nine months ended September 30, 2020 were as follows:

	Three Months Ended September 30, 2020		Nine Months Ended September 30, 2020
Commercial and industrial	$	10,224	$	25,340
Energy	7,144		38,642
Commercial real estate:
Buildings, land and other	637		8,094
Construction	—		—
Consumer real estate	421		2,132
Consumer and other	5,494		15,338
Total	$	23,920	$	89,546

Financing Receivable, Allowance for Credit Loss By Loan Class Calculated in Accordance With CECL Methodology

The following table presents details of the allowance for credit losses on loans segregated by loan portfolio segment as of September 30, 2020, calculated in accordance with the CECL methodology described above. No allowance for credit losses has been recognized for PPP loans as such loans are fully guaranteed by the SBA.

	Commercial and Industrial		Energy		Commercial Real Estate		Consumer Real Estate		Consumer and Other		Total
Modeled expected credit losses	$	68,896	$	21,644	$	125,965	$	10,226	$	7,420	$	234,151
Q-Factor and other qualitative adjustments	(1,647)		24,630		(8,685)		51		31		14,380
Specific allocations	5,256		8,357		1,313		—		18		14,944
Total	$	72,505	$	54,631	$	118,593	$	10,277	$	7,469	$	263,475

Allowance for Credit Losses By Loan Class in Accordance With Methodology Used Prior to CECL

The following table presents details of the allowance for credit losses on loans segregated by loan portfolio segment as of December 31, 2019, calculated in accordance with our prior incurred loss methodology described in our 2019 Form 10-K.

	Commercial and Industrial		Energy		Commercial Real Estate		Consumer Real Estate		Consumer and Other		Total
Historical valuation allowances	$	29,015	$	7,873	$	21,947	$	2,690	$	7,562	$	69,087
Specific valuation allowances	7,849		20,246		383		—		5		28,483
General valuation allowances	9,840		5,196		4,201		904		(409)		19,732
Macroeconomic valuation allowances	4,889		4,067		4,506		519		884		14,865
Total	$	51,593	$	37,382	$	31,037	$	4,113	$	8,042	$	132,167

Activity in Allowance for Loan Losses by Portfolio Segment

The following table details activity in the allowance for credit losses on loans by portfolio segment for the three and nine months ended September 30, 2020 and 2019. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. No allowance for credit losses has been recognized for PPP loans as such loans are fully guaranteed by the SBA.

	Commercial and Industrial		Energy		Commercial Real Estate		Consumer Real Estate		Consumer and Other		Total
Three months ended:
September 30, 2020
Beginning balance	$	98,536	$	40,817	$	93,425	$	8,998	$	8,285	$	250,061
Credit loss expense	(18,547)		13,814		25,368		1,794		1,161		23,590
Charge-offs	(8,605)		—		(242)		(1,088)		(4,219)		(14,154)
Recoveries	1,121		—		42		573		2,242		3,978
Net charge-offs	(7,484)		—		(200)		(515)		(1,977)		(10,176)
Ending balance	$	72,505	$	54,631	$	118,593	$	10,277	$	7,469	$	263,475
September 30, 2019
Beginning balance	$	57,714	$	25,818	$	35,914	$	5,637	$	9,846	$	134,929
Credit loss expense	(3,527)		8,788		(607)		(650)		3,997		8,001
Charge-offs	(2,705)		(2,000)		—		(557)		(6,357)		(11,619)
Recoveries	1,185		740		46		454		2,823		5,248
Net charge-offs	(1,520)		(1,260)		46		(103)		(3,534)		(6,371)
Ending balance	$	52,667	$	33,346	$	35,353	$	4,884	$	10,309	$	136,559
Nine months ended:
September 30, 2020
Beginning balance	$	51,593	$	37,382	$	31,037	$	4,113	$	8,042	$	132,167
Impact of adopting ASC 326	21,263		(10,453)		(13,519)		2,392		(2,248)		(2,565)
Credit loss expense	10,737		96,478		104,716		3,716		8,096		223,743
Charge-offs	(14,815)		(68,842)		(3,826)		(1,508)		(13,402)		(102,393)
Recoveries	3,727		66		185		1,564		6,981		12,523
Net charge-offs	(11,088)		(68,776)		(3,641)		56		(6,421)		(89,870)
Ending balance	$	72,505	$	54,631	$	118,593	$	10,277	$	7,469	$	263,475
September 30, 2019
Beginning balance	$	48,580	$	29,052	$	38,777	$	6,103	$	9,620	$	132,132
Credit loss expense	9,999		7,478		(2,972)		859		10,040		25,404
Charge-offs	(8,782)		(4,000)		(617)		(2,936)		(17,157)		(33,492)
Recoveries	2,870		816		165		858		7,806		12,515
Net charge-offs	(5,912)		(3,184)		(452)		(2,078)		(9,351)		(20,977)
Ending balance	$	52,667	$	33,346	$	35,353	$	4,884	$	10,309	$	136,559

Investment in Loans Related to Allowance for Loan Losses by Portfolio Segment Disaggregated Based on Impairment Methodology

The following table presents loans that were evaluated for expected credit losses on an individual basis and the related specific allocations, by loan portfolio segment as of September 30, 2020 and December 31, 2019.

	September 30, 2020				December 31, 2019
	Loan Balance		Specific Allocations		Loan Balance		Specific Allocations
Commercial and industrial	$	22,930	$	5,256	$	24,360	$	7,849
Energy	56,420		8,357		65,244		20,246
Paycheck Protection Program	—		—		—		—
Commercial real estate:
Buildings, land and other	25,611		1,313		8,609		383
Construction	680		—		665		—
Consumer real estate	1,335		—		570		—
Consumer and other	18		18		5		5
Total	$	106,994	$	14,944	$	99,453	$	28,483