Loans and Allowances for Credit Losses

Loans

Loans are either secured or unsecured based on the type of loan and the financial condition of the borrower. Repayment is generally expected from cash flow or proceeds from the sale of selected assets of the borrower. BOK Financial is exposed to risk of loss on loans due to the borrower’s difficulties, which may arise from any number of factors, including problems within the respective industry or local economic conditions. Access to collateral, in the event of borrower default, is reasonably assured through adherence to applicable lending laws and through sound lending standards and credit review procedures. Accounting policies for all loans, excluding residential mortgage loans guaranteed by U.S. government agencies, are as follows.

Interest is accrued at the applicable interest rate on the principal amount outstanding. Loans are placed on nonaccruing status when, in the opinion of management, full collection of principal or interest is uncertain. Internally risk graded loans are individually evaluated for nonaccruing status quarterly. Non-risk graded loans are generally placed on nonaccruing status when more than 90 days past due or within 60 days of being notified of the borrower's bankruptcy filing. Interest previously accrued but not collected is charged against interest income when the loan is placed on nonaccruing status. Payments on nonaccruing loans are applied to principal or recognized as interest income, according to management’s judgment as to the collectability of principal. Loans may be returned to accruing status when, in the opinion of management, full collection of principal and interest, including principal previously charged off, is probable based on improvements in the borrower’s financial condition or a sustained period of performance.

Loans to borrowers experiencing financial difficulties may be modified in troubled debt restructurings ("TDRs"). All TDRs are classified as nonaccruing, excluding loans guaranteed by U.S. government agencies. Modifications generally consist of extension of payment terms or interest rate concessions and may result either voluntarily through negotiations with the borrower or involuntarily through court order. Generally, principal and accrued but unpaid interest is not voluntarily forgiven.

Performing loans may be renewed under the current collateral value, debt service ratio and other underwriting standards. Nonaccruing loans may be renewed and will remain classified as nonaccruing.

All loans are charged off when the loan balance or a portion of the loan balance is no longer supported by the paying capacity of the borrower or when the required cash flow is reduced in a TDR. The charge-off amount is determined through a quarterly evaluation of available cash resources and collateral value and charge-offs are taken in the quarter in which the loss is identified. Non-risk graded loans that are past due between 60 days and 180 days, based on the loan product type, are charged off. Loans to borrowers whose personal obligation has been discharged through Chapter 7 bankruptcy proceedings are charged off within 60 days of notice of the bankruptcy filing, regardless of payment status.

Loan origination and commitment fees and direct loan acquisition and origination costs are deferred and amortized as an adjustment to yield over the life of the loan or over the commitment period, as applicable.

Qualifying residential mortgage loans guaranteed by U.S. government agencies have been sold into GNMA pools. Under certain performance conditions specified in government programs, the Company may have the right, but not the obligation to repurchase loans from GNMA pools. These loans no longer qualify for sale accounting and are recognized in the Consolidated Balance Sheets. Guaranteed loans are considered impaired because we do not expect to receive all principal and interest based on the loan's contractual terms. The principal balance continues to be guaranteed; however, interest accrues at a curtailed rate as specified in the programs. The carrying value of these loans is reduced based on an estimate of the expected cash flows discounted at the original note rate plus a liquidity spread. Guaranteed loans may be modified in TDRs in accordance with U.S. government agency guidelines. Interest continues to accrue based on the modified rate. Guaranteed loans may either be resold into GNMA pools after a performance period specified by the programs or foreclosed and conveyed to the guarantors.

Loans are disaggregated into portfolio segments and further disaggregated into classes. The portfolio segment is the level at which the Company develops and documents a systematic method for determining its allowance for credit losses. Classes are a further disaggregation of portfolio segments based on the risk characteristics of the loans and the Company’s method for monitoring and assessing credit risk.

Portfolio segments of the loan portfolio are as follows (in thousands):



	September 30, 2017								December 31, 2016
	Fixed Rate		Variable Rate		Non-accrual		Total		Fixed Rate		Variable Rate		Non-accrual		Total
Commercial	$	2,225,470	$	8,393,564	$	176,900	$	10,795,934	$	2,327,085	$	7,884,786	$	178,953	$	10,390,824
Commercial real estate	564,681		2,950,486		2,975		3,518,142		624,187		3,179,338		5,521		3,809,046
Residential mortgage	1,589,013		311,231		45,506		1,945,750		1,647,357		256,255		46,220		1,949,832
Personal	153,750		793,003		255		947,008		154,971		684,697		290		839,958
Total	$	4,532,914	$	12,448,284	$	225,636	$	17,206,834	$	4,753,600	$	12,005,076	$	230,984	$	16,989,660
Accruing loans past due (90 days)¹							$	253							$	5



	September 30, 2016
	Fixed Rate		Variable Rate		Non-accrual		Total
Commercial	$	1,991,423	$	7,952,276	$	176,464	$	10,120,163
Commercial real estate	565,429		3,220,819		7,350		3,793,598
Residential mortgage	1,572,288		248,053		52,452		1,872,793
Personal	104,408		573,138		686		678,232
Total	$	4,233,548	$	11,994,286	$	236,952	$	16,464,786
Accruing loans past due (90 days)¹							$	3,839


¹	Excludes residential mortgage loans guaranteed by agencies of the U.S. government

At September 30, 2017, $5.9 billion or 34 percent of our total loan portfolio is to businesses and individuals attributed to the Texas market and $3.4 billion or 20 percent of the total loan portfolio is to businesses and individuals attributed to the Oklahoma market. These geographic concentrations subject the loan portfolio to the general economic conditions within these areas.

Commercial

Commercial loans represent loans for working capital, facilities acquisition or expansion, purchases of equipment and other needs of commercial customers primarily located within our geographical footprint. Commercial loans are underwritten individually and represent ongoing relationships based on a thorough knowledge of the customer, the customer’s industry and market. While commercial loans are generally secured by the customer’s assets including real property, inventory, accounts receivable, operating equipment, interest in mineral rights and other property and may also include personal guarantees of the owners and related parties, the primary source of repayment of the loans is the ongoing cash flow from operations of the customer’s business. Inherent lending risk is centrally monitored on a continuous basis from underwriting throughout the life of the loan for compliance with commercial lending policies.

At September 30, 2017, commercial loans attributed to the Texas market totaled $3.7 billion or 34 percent of the commercial loan portfolio segment and commercial loans attributed to the Oklahoma market totaled $2.1 billion or 19 percent of the commercial loan portfolio segment.

The commercial loan portfolio segment is further divided into loan classes. The energy loan class totaled $2.9 billion or 17 percent of total loans at September 30, 2017, including $2.3 billion of outstanding loans to energy producers. Approximately 57 percent of committed production loans are secured by properties primarily producing oil and 43 percent are secured by properties producing natural gas. The services loan class totaled $3.0 billion or 17 percent of total loans at September 30, 2017. Approximately $1.5 billion of loans in the services category consist of loans with individual balances of less than $10 million. Businesses included in the services class include governmental, educational services, consumer services, loans to entities providing services for real estate and construction and commercial services. The healthcare loan class totaled $2.2 billion or 13 percent of total loans at September 30, 2017. The healthcare loan class consists primarily of loans for the development and operation of senior housing and care facilities, including independent living, assisted living and skilled nursing. Healthcare also includes loans to hospitals and other medical service providers.

Commercial Real Estate

Commercial real estate loans are for the construction of buildings or other improvements to real estate and property held by borrowers for investment purposes primarily within our geographical footprint. We require collateral values in excess of the loan amounts, demonstrated cash flows in excess of expected debt service requirements, equity investment in the project and a portion of the project already sold, leased or permanent financing already secured. The expected cash flows from all significant new or renewed income producing property commitments are stress tested to reflect the risks in varying interest rates, vacancy rates and rental rates. As with commercial loans, inherent lending risks are centrally monitored on a continuous basis from underwriting throughout the life of the loan for compliance with applicable lending policies.

At September 30, 2017, 35 percent of commercial real estate loans are secured by properties primarily located in the Dallas and Houston areas of Texas. An additional 13 percent of commercial real estate loans are secured by properties located primarily in the Tulsa and Oklahoma City metropolitan areas of Oklahoma.

Residential Mortgage and Personal

Residential mortgage loans provide funds for our customers to purchase or refinance their primary residence or to borrow against the equity in their home. Residential mortgage loans are secured by a first or second mortgage on the customer’s primary residence. Personal loans consist primarily of loans secured by the cash surrender value of insurance policies and marketable securities. It also includes direct loans secured by and for the purchase of automobiles, recreational and marine equipment as well as unsecured loans. Residential mortgage and personal loans are made in accordance with underwriting policies we believe to be conservative and are fully documented. Loans may be individually underwritten or credit scored based on size and other criteria. Credit scoring is assessed based on significant credit characteristics including credit history, residential and employment stability. Residential mortgage loans retained in the Company’s portfolio are primarily composed of various mortgage programs to support customer relationships including jumbo mortgage loans, non-builder construction loans and special loan programs for high net worth individuals and certain professionals. Jumbo loans may be fixed or variable rate and are fully amortizing. Jumbo loans generally conform to government sponsored entity standards, except that the loan size exceeds maximums required under these standards. These loans generally require a minimum FICO score of 720 and a maximum debt-to-income ratio (“DTI”) of 38 percent. Loan-to-value (“LTV”) ratios are tiered from 60 percent to 100 percent, depending on the market. Special mortgage programs include fixed and variable fully amortizing loans tailored to the needs of certain healthcare professionals. Variable rate loans are fully indexed at origination and may have fixed rates for three to ten years, then adjust annually thereafter.

At September 30, 2017, residential mortgage loans included $187 million of loans guaranteed by U.S. government agencies previously sold into GNMA mortgage pools. These loans either have been repurchased or are eligible to be repurchased by the Company when certain defined delinquency criteria are met. Although payments on these loans generally are past due more than 90 days, interest continues to accrue based on the government guarantee.

Home equity loans totaled $744 million at September 30, 2017. Approximately 64 percent of the home equity loan portfolio is comprised of first lien loans and 36 percent of the home equity portfolio is comprised of junior lien loans. Junior lien loans are distributed 47 percent to amortizing term loans and 53 percent to revolving lines of credit. Home equity loans generally require a minimum FICO score of 700 and a maximum DTI of 40 percent. The maximum loan amount available for our home equity loan products is generally $400 thousand. Revolving loans have a 5 year revolving period followed by a 15 year term of amortizing repayments. Interest-only home equity loans may not be extended for any additional revolving time. All other home equity loans may be extended at management's discretion for an additional 5 year revolving term, subject to an update of certain credit information.

Credit Commitments

Commitments to extend credit are agreements to lend to a customer as long as there is no violation of conditions established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. At September 30, 2017, outstanding commitments totaled $9.7 billion. Because some commitments are expected to expire before being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. BOK Financial uses the same credit policies in making commitments as it does loans.

The amount of collateral obtained, if deemed necessary, is based upon management’s credit evaluation of the borrower.

Standby letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. Because the credit risk involved in issuing standby letters of credit is essentially the same as that involved in extending loan commitments, BOK Financial uses the same credit policies in evaluating the creditworthiness of the customer. Additionally, BOK Financial uses the same evaluation process in obtaining collateral on standby letters of credit as it does for loan commitments. The term of these standby letters of credit is defined in each commitment and typically corresponds with the underlying loan commitment. At September 30, 2017, outstanding standby letters of credit totaled $666 million. Commercial letters of credit are used to facilitate customer trade transactions with the drafts being drawn when the underlying transaction is consummated. At September 30, 2017, outstanding commercial letters of credit totaled $2.3 million.

Allowances for Credit Losses

BOK Financial maintains an allowance for loan losses and an accrual for off-balance sheet credit risk. The accrual for off-balance sheet credit risk is maintained at a level that is appropriate to cover estimated losses associated with credit instruments that are not currently recognized as assets such as loan commitments, standby letters of credit or guarantees. As discussed in greater detail in Note 6, the Company also has separate accruals for off-balance sheet credit risk related to residential mortgage loans previously sold with full or partial recourse and for residential mortgage loans sold to government sponsored agencies under standard representations and warranties.

The appropriateness of the allowance for loan losses and accrual for off-balance sheet credit losses (collectively "allowance for credit losses") is assessed by management based on an ongoing quarterly evaluation of the probable estimated losses inherent in the portfolio, including probable losses on both outstanding loans and unused commitments.

The allowance for loan losses consists of specific allowances attributed to impaired loans that have not yet been charged down to amounts we expect to recover, general allowances for unimpaired loans based on estimated loss rates by loan class and nonspecific allowances based on general economic conditions, risk concentration and related factors. There have been no material changes in the approach or techniques utilized in developing the allowance for loan losses and the accrual for off-balance sheet credit losses for the three and nine months ended September 30, 2017.

Loans are considered to be impaired when it becomes probable that BOK Financial will be unable to collect all amounts due according to the contractual terms of the loan agreements. Internally risk graded loans are evaluated individually for impairment. Substantially all commercial and commercial real estate loans and certain residential mortgage and consumer loans are risk graded based on evaluation of the borrowers' ability to repay. Certain commercial loans and most residential mortgage and consumer loans are small balance, homogeneous pools of loans that are not risk graded. Non-risk graded loans are identified as impaired based on performance status. Generally, non-risk graded loans 90 days or more past due or modified in a TDR or in bankruptcy are considered to be impaired.

Specific allowances for impaired loans are measured by an evaluation of estimated future cash flows discounted at the loans’ initial effective interest rate or the fair value of collateral for certain collateral dependent loans. Collateral value of real property is generally based on third party appraisals that conform to Uniform Standards of Professional Appraisal Practice, less estimated selling costs. Appraised values are on an "as-is" basis and are generally not adjusted by the Company. Updated appraisals are obtained at least annually or more frequently if market conditions indicate collateral values have declined. Collateral value of mineral rights is generally determined by our internal staff of engineers based on projected cash flows under current market conditions. Collateral values and available cash resources that support impaired loans are evaluated quarterly. Historical statistics may be used as a practical way to estimate impairment in limited situations, such as when a collateral dependent loan is identified as impaired at the end of a reporting period, until an updated appraisal of collateral value is received or a full assessment of future cash flows is completed. Estimates of future cash flows and collateral values require significant judgments and may be volatile.

General allowances for unimpaired loans are based on estimated loss rates by loan class. The gross loss rate for each loan class is determined by the greater of the current gross loss rate based on the most recent twelve months or a ten-year gross loss rate. Recoveries are not directly considered in the estimation of loss rates. Recoveries generally do not follow predictable patterns and are not received until well after the charge-off date as a result of protracted legal actions. For risk graded loans, gross loss rates are adjusted for changes in risk grading. For each loan class, the current weighted average risk grade is compared to the long-term average risk grade. This comparison determines whether credit risk in each loan class is increasing or decreasing. Loss rates are adjusted upward or downward in proportion to changes in average risk grading. General allowances for unimpaired loans also consider inherent risks identified for each loan class. Inherent risks consider loss rates that most appropriately represent the current credit cycle and other factors attributable to specific loan classes which have not yet been represented in the gross loss rates or risk grading. These factors include changes in commodity prices or engineering imprecision, which may affect the value of reserves that secure our energy loan portfolio, construction risk that may affect commercial real estate loans, changes in regulations and public policy that may disproportionately impact health care loans and changes in loan products.

Nonspecific allowances are maintained for risks beyond factors specific to a particular loan or loan class. These factors include trends in the economy of our primary lending areas, concentrations in large balance loans and other relevant factors.

An accrual for off-balance sheet credit losses is included in Other liabilities in the Consolidated Balance Sheets. The appropriateness of this accrual is determined in the same manner as the allowance for loan losses.

A provision for credit losses is charged against or credited to earnings in amounts necessary to maintain an appropriate allowance for credit losses. Recoveries of loans previously charged off are added to the allowance when received.

The activity in the allowance for loan losses and the allowance for off-balance sheet credit losses related to loan commitments and standby letters of credit for the three months ended September 30, 2017 is summarized as follows (in thousands):



	Commercial			Commercial Real Estate			Residential Mortgage			Personal			Nonspecific Allowance		Total
Allowance for loan losses:
Beginning balance	$	137,742		$	58,580		$	18,259		$	8,106		$	27,374	$	250,061
Provision for loan losses	2,474			(2,914		)	168			598			704		1,030
Loans charged off	(4,429		)	—			(168		)	(1,228		)	—		(5,825		)
Recoveries	1,014			739			134			550			—		2,437
Ending balance	$	136,801		$	56,405		$	18,393		$	8,026		$	28,078	$	247,703
Allowance for off-balance sheet credit losses:
Beginning balance	$	6,301		$	84		$	38		$	8		$	—	$	6,431
Provision for off-balance sheet credit losses	(976		)	(49		)	1			(6		)	—		(1,030		)
Ending balance	$	5,325		$	35		$	39		$	2		$	—	$	5,401

Total provision for credit losses	$	1,498		$	(2,963	)	$	169		$	592		$	704	$	—

The activity in the allowance for loan losses and the allowance for off-balance sheet credit losses related to loan commitments and standby letters of credit for the nine months ended September 30, 2017 is summarized as follows (in thousands):



	Commercial			Commercial Real Estate			Residential Mortgage			Personal			Nonspecific Allowance			Total
Allowance for loan losses:
Beginning balance	$	140,213		$	50,749		$	18,224		$	8,773		$	28,200		$	246,159
Provision for loan losses	665			4,050			82			1,168			(122		)	5,843
Loans charged off	(6,556		)	(76		)	(444		)	(3,774		)	—			(10,850		)
Recoveries	2,479			1,682			531			1,859			—			6,551
Ending balance	$	136,801		$	56,405		$	18,393		$	8,026		$	28,078		$	247,703
Allowance for off-balance sheet credit losses:
Beginning balance	$	11,063		$	123		$	50		$	8		$	—		$	11,244
Provision for off-balance sheet credit losses	(5,738		)	(88		)	(11		)	(6		)	—			(5,843		)
Ending balance	$	5,325		$	35		$	39		$	2		$	—		$	5,401

Total provision for credit losses	$	(5,073	)	$	3,962		$	71		$	1,162		$	(122	)	$	—



	Commercial			Commercial Real Estate			Residential Mortgage			Personal			Nonspecific Allowance		Total
Allowance for loan losses:
Beginning balance	$	145,139		$	46,745		$	18,690		$	6,001		$	26,684	$	243,259
Provision for loan losses	2,420			2,551			(466		)	1,900			1,502		7,907
Loans charged off	(6,266		)	—			(285		)	(1,550		)	—		(8,101		)
Recoveries	177			521			650			690			—		2,038
Ending balance	$	141,470		$	49,817		$	18,589		$	7,041		$	28,186	$	245,103
Allowance for off-balance sheet credit losses:
Beginning balance	$	8,752		$	203		$	62		$	28		$	—	$	9,045
Provision for off-balance sheet credit losses	2,170			(53		)	(7		)	(17		)	—		2,093
Ending balance	$	10,922		$	150		$	55		$	11		$	—	$	11,138

Total provision for credit losses	$	4,590		$	2,498		$	(473	)	$	1,883		$	1,502	$	10,000



	Commercial			Commercial Real Estate			Residential Mortgage			Personal			Nonspecific Allowance			Total
Allowance for loan losses:
Beginning balance	$	130,334		$	41,391		$	19,509		$	4,164		$	30,126		$	225,524
Provision for loan losses	45,995			7,538			(829		)	4,809			(1,940		)	55,573
Loans charged off	(35,747		)	—			(1,104		)	(4,086		)	—			(40,937		)
Recoveries	888			888			1,013			2,154			—			4,943
Ending balance	$	141,470		$	49,817		$	18,589		$	7,041		$	28,186		$	245,103
Allowance for off-balance sheet credit losses:
Beginning balance	$	1,506		$	153		$	30		$	22		$	—		$	1,711
Provision for off-balance sheet credit losses	9,416			(3		)	25			(11		)	—			9,427
Ending balance	$	10,922		$	150		$	55		$	11		$	—		$	11,138

Total provision for credit losses	$	55,411		$	7,535		$	(804	)	$	4,798		$	(1,940	)	$	65,000

The allowance for loan losses and recorded investment of the related loans by portfolio segment for each impairment measurement method at September 30, 2017 is as follows (in thousands):



	Collectively Measured for Impairment				Individually Measured for Impairment				Total
	Recorded Investment		Related Allowance		Recorded Investment		Related Allowance		Recorded Investment		Related Allowance
Commercial	$	10,619,034	$	123,517	$	176,900	$	13,284	$	10,795,934	$	136,801
Commercial real estate	3,515,167		56,405		2,975		—		3,518,142		56,405
Residential mortgage	1,900,244		18,393		45,506		—		1,945,750		18,393
Personal	946,753		8,026		255		—		947,008		8,026
Total	16,981,198		206,341		225,636		13,284		17,206,834		219,625

Nonspecific allowance	—		—		—		—		—		28,078

Total	$	16,981,198	$	206,341	$	225,636	$	13,284	$	17,206,834	$	247,703

The allowance for loan losses and recorded investment of the related loans by portfolio segment for each impairment measurement method at December 31, 2016 is as follows (in thousands):



	Collectively Measured for Impairment				Individually Measured for Impairment				Total
	Recorded Investment		Related Allowance		Recorded Investment		Related Allowance		Recorded Investment		Related Allowance
Commercial	$	10,211,871	$	139,416	$	178,953	$	797	$	10,390,824	$	140,213
Commercial real estate	3,803,525		50,749		5,521		—		3,809,046		50,749
Residential mortgage	1,903,612		18,178		46,220		46		1,949,832		18,224
Personal	839,668		8,773		290		—		839,958		8,773
Total	16,758,676		217,116		230,984		843		16,989,660		217,959

Nonspecific allowance	—		—		—		—		—		28,200

Total	$	16,758,676	$	217,116	$	230,984	$	843	$	16,989,660	$	246,159

The allowance for loan losses and recorded investment of the related loans by portfolio segment for each impairment measurement method at September 30, 2016 is as follows (in thousands):



	Collectively Measured for Impairment				Individually Measured for Impairment				Total
	Recorded Investment		Related Allowance		Recorded Investment		Related Allowance		Recorded Investment		Related Allowance
Commercial	$	9,943,699	$	134,968	$	176,464	$	6,502	$	10,120,163	$	141,470
Commercial real estate	3,786,248		49,817		7,350		—		3,793,598		49,817
Residential mortgage	1,820,341		18,527		52,452		62		1,872,793		18,589
Personal	677,546		7,041		686		—		678,232		7,041
Total	16,227,834		210,353		236,952		6,564		16,464,786		216,917

Nonspecific allowance	—		—		—		—		—		28,186

Total	$	16,227,834	$	210,353	$	236,952	$	6,564	$	16,464,786	$	245,103

Credit Quality Indicators

The Company utilizes loan class and risk grading as primary credit quality indicators. Substantially all commercial and commercial real estate loans and certain residential mortgage and consumer loans are risk graded based on a quarterly evaluation of the borrowers’ ability to repay the loans. Certain commercial loans and most residential mortgage and consumer loans are small, homogeneous pools that are not risk graded.

The allowance for loan losses and recorded investment of the related loans by portfolio segment for risk graded and non-risk graded loans at September 30, 2017 is as follows (in thousands):



	Internally Risk Graded				Non-Graded				Total
	Recorded Investment		Related Allowance		Recorded Investment		Related Allowance		Recorded Investment		Related Allowance
Commercial	$	10,750,657	$	135,846	$	45,277	$	955	$	10,795,934	$	136,801
Commercial real estate	3,518,142		56,405		—		—		3,518,142		56,405
Residential mortgage	226,306		3,068		1,719,444		15,325		1,945,750		18,393
Personal	856,030		6,043		90,978		1,983		947,008		8,026
Total	15,351,135		201,362		1,855,699		18,263		17,206,834		219,625

Nonspecific allowance	—		—		—		—		—		28,078

Total	$	15,351,135	$	201,362	$	1,855,699	$	18,263	$	17,206,834	$	247,703

The allowance for loan losses and recorded investment of the related loans by portfolio segment for risk graded and non-risk graded loans at December 31, 2016 is as follows (in thousands):



	Internally Risk Graded				Non-Graded				Total
	Recorded Investment		Related Allowance		Recorded Investment		Related Allowance		Recorded Investment		Related Allowance
Commercial	$	10,360,725	$	139,293	$	30,099	$	920	$	10,390,824	$	140,213
Commercial real estate	3,809,046		50,749		—		—		3,809,046		50,749
Residential mortgage	243,703		2,893		1,706,129		15,331		1,949,832		18,224
Personal	744,602		5,035		95,356		3,738		839,958		8,773
Total	15,158,076		197,970		1,831,584		19,989		16,989,660		217,959

Nonspecific allowance	—		—		—		—		—		28,200

Total	$	15,158,076	$	197,970	$	1,831,584	$	19,989	$	16,989,660	$	246,159

The allowance for loan losses and recorded investment of the related loans by portfolio segment for risk graded and non-risk graded loans at September 30, 2016 is as follows (in thousands):



	Internally Risk Graded				Non-Graded				Total
	Recorded Investment		Related Allowance		Recorded Investment		Related Allowance		Recorded Investment		Related Allowance
Commercial	$	10,093,884	$	140,552	$	26,279	$	918	$	10,120,163	$	141,470
Commercial real estate	3,793,598		49,817		—		—		3,793,598		49,817
Residential mortgage	206,430		3,028		1,666,363		15,561		1,872,793		18,589
Personal	586,869		4,182		91,363		2,859		678,232		7,041
Total	14,680,781		197,579		1,784,005		19,338		16,464,786		216,917

Nonspecific allowance	—		—		—		—		—		28,186

Total	$	14,680,781	$	197,579	$	1,784,005	$	19,338	$	16,464,786	$	245,103

Loans are considered to be performing if they are in compliance with the original terms of the agreement and currently exhibit no factors that cause management to have doubts about the borrowers' ability to remain in compliance with the original terms of the agreement, which is consistent with the regulatory guideline of “pass.” Performing loans also include past due residential mortgages that are guaranteed by agencies of the U.S. government that continue to accrue interest based on criteria of the guarantors' programs. Other loans especially mentioned are currently performing in compliance with the original terms of the agreement but may have a potential weakness that deserves management’s close attention, consistent with regulatory guidelines.

The risk grading process identified certain loans that have a well-defined weakness (e.g. inadequate debt service coverage or liquidity or marginal capitalization; repayment may depend on collateral or other risk mitigation) that may jeopardize liquidation of the debt and represent a greater risk due to deterioration in the financial condition of the borrower. This is consistent with the regulatory guideline for “substandard.” Because the borrowers are still performing in accordance with the original terms of the loan agreements, these loans were not placed in nonaccruing status.

Nonaccruing loans represent loans for which full collection of principal and interest is uncertain. This is substantially the same criteria used to determine whether a loan is impaired and includes certain loans considered “substandard” and all loans considered “doubtful” by regulatory guidelines.

The following table summarizes the Company’s loan portfolio at September 30, 2017 by the risk grade categories (in thousands):



	Internally Risk Graded								Non-Graded
	Performing
	Pass		Other Loans Especially Mentioned		Accruing Substandard		Nonaccrual		Performing		Nonaccrual		Total
Commercial:
Energy	$	2,436,465	$	114,065	$	206,768	$	110,683	$	—	$	—	$	2,867,981
Services	2,932,577		26,372		7,390		1,174		—		—		2,967,513
Wholesale/retail	1,637,698		9,021		9,486		1,893		—		—		1,658,098
Manufacturing	486,383		7,181		16,823		9,059		—		—		519,446
Healthcare	2,150,099		31,855		33,051		24,446		—		—		2,239,451
Other commercial and industrial	458,796		52		9,820		29,500		45,132		145		543,445
Total commercial	10,102,018		188,546		283,338		176,755		45,132		145		10,795,934

Commercial real estate:
Residential construction and land development	110,178		—		—		1,924		—		—		112,102
Retail	724,887		689		—		289		—		—		725,865
Office	788,539		8,275		—		275		—		—		797,089
Multifamily	998,125		—		884		—		—		—		999,009
Industrial	591,080		—		—		—		—		—		591,080
Other commercial real estate	292,509		—		1		487		—		—		292,997
Total commercial real estate	3,505,318		8,964		885		2,975		—		—		3,518,142

Residential mortgage:
Permanent mortgage	224,235		393		462		1,216		764,252		23,407		1,013,965
Permanent mortgages guaranteed by U.S. government agencies	—		—		—		—		178,479		8,891		187,370
Home equity	—		—		—		—		732,423		11,992		744,415
Total residential mortgage	224,235		393		462		1,216		1,675,154		44,290		1,945,750

Personal	855,857		49		38		86		90,809		169		947,008

Total	$	14,687,428	$	197,952	$	284,723	$	181,032	$	1,811,095	$	44,604	$	17,206,834

The following table summarizes the Company’s loan portfolio at December 31, 2016 by the risk grade categories (in thousands):



	Internally Risk Graded								Non-Graded
	Performing
	Pass		Other Loans Especially Mentioned		Accruing Substandard		Nonaccrual		Performing		Nonaccrual		Total
Commercial:
Energy	$	1,937,790	$	119,583	$	307,996	$	132,499	$	—	$	—	$	2,497,868
Services	3,052,002		10,960		37,855		8,173		—		—		3,108,990
Wholesale/retail	1,535,463		16,886		13,062		11,407		—		—		1,576,818
Manufacturing	468,314		26,532		15,198		4,931		—		—		514,975
Healthcare	2,140,458		44,472		16,161		825		—		—		2,201,916
Other commercial and industrial	433,789		5,309		—		21,060		30,041		58		490,257
Total commercial	9,567,816		223,742		390,272		178,895		30,041		58		10,390,824

Commercial real estate:
Residential construction and land development	131,630		—		470		3,433		—		—		135,533
Retail	756,418		4,745		399		326		—		—		761,888
Office	798,462		—		—		426		—		—		798,888
Multifamily	898,800		—		4,434		38		—		—		903,272
Industrial	871,673		—		—		76		—		—		871,749
Other commercial real estate	336,488		—		6		1,222		—		—		337,716
Total commercial real estate	3,793,471		4,745		5,309		5,521		—		—		3,809,046

Residential mortgage:
Permanent mortgage	238,769		1,186		2,331		1,417		741,679		21,438		1,006,820
Permanent mortgages guaranteed by U.S. government agencies	—		—		—		—		187,541		11,846		199,387
Home equity	—		—		—		—		732,106		11,519		743,625
Total residential mortgage	238,769		1,186		2,331		1,417		1,661,326		44,803		1,949,832

Personal	743,451		—		1,054		97		95,163		193		839,958

Total	$	14,343,507	$	229,673	$	398,966	$	185,930	$	1,786,530	$	45,054	$	16,989,660

The following table summarizes the Company’s loan portfolio at September 30, 2016 by the risk grade categories (in thousands):



	Internally Risk Graded								Non-Graded
	Performing
	Pass		Other Loans Especially Mentioned		Accruing Substandard		Nonaccrual		Performing		Nonaccrual		Total
Commercial:
Energy	$	1,869,598	$	147,153	$	361,087	$	142,966	$	—	$	—	$	2,520,804
Services	2,882,065		14,861		31,196		8,477		—		—		2,936,599
Wholesale/retail	1,557,067		15,337		27,173		2,453		—		—		1,602,030
Manufacturing	470,702		8,774		19,736		274		—		—		499,486
Healthcare	2,022,757		42,224		19,210		855		—		—		2,085,046
Other commercial and industrial	415,769		2,478		10,302		21,370		26,210		69		476,198
Total commercial	9,217,958		230,827		468,704		176,395		26,210		69		10,120,163

Commercial real estate:
Residential construction and land development	155,737		—		470		3,739		—		—		159,946
Retail	794,920		4,802		406		1,249		—		—		801,377
Office	750,924		899		—		882		—		—		752,705
Multifamily	868,501		—		5,221		51		—		—		873,773
Industrial	837,945		—		—		76		—		—		838,021
Other commercial real estate	366,416		—		7		1,353		—		—		367,776
Total commercial real estate	3,774,443		5,701		6,104		7,350		—		—		3,793,598

Residential mortgage:
Permanent mortgage	200,590		1,192		2,134		2,514		739,686		23,442		969,558
Permanent mortgages guaranteed by U.S. government agencies	—		—		—		—		174,877		15,432		190,309
Home equity	—		—		—		—		701,862		11,064		712,926
Total residential mortgage	200,590		1,192		2,134		2,514		1,616,425		49,938		1,872,793

Personal	585,287		228		923		431		91,108		255		678,232

Total	$	13,778,278	$	237,948	$	477,865	$	186,690	$	1,733,743	$	50,262	$	16,464,786

Impaired Loans

Loans are considered to be impaired when it is probable that the Company will not be able to collect all amounts due according to the contractual terms of the loan agreement. This includes all nonaccruing loans, all loans modified in a TDR and all loans repurchased from GNMA pools.

A summary of impaired loans follows (in thousands):



	As of										For the				For the
	September 30, 2017										Three Months Ended				Nine Months Ended
			Recorded Investment								September 30, 2017				September 30, 2017
	Unpaid Principal Balance		Total		With No Allowance		With Allowance		Related Allowance		Average Recorded Investment		Interest Income Recognized		Average Recorded Investment		Interest Income Recognized
Commercial:
Energy	$	133,643	$	110,683	$	45,169	$	65,514	$	4,944	$	117,338	$	—	$	121,591	$	—
Services	3,838		1,174		1,174		—		—		4,464		—		4,674		—
Wholesale/retail	8,418		1,893		1,893		—		—		6,256		—		6,650		—
Manufacturing	9,674		9,059		9,059		—		—		9,357		—		6,995		—
Healthcare	24,591		24,446		474		23,972		8,323		24,476		—		12,635		—
Other commercial and industrial	38,222		29,645		29,626		19		17		25,138		—		25,382		—
Total commercial	218,386		176,900		87,395		89,505		13,284		187,029		—		177,927		—

Commercial real estate:
Residential construction and land development	3,532		1,924		1,924		—		—		1,988		—		2,679		—
Retail	513		289		289		—		—		295		—		308		—
Office	287		275		275		—		—		335		—		351		—
Multifamily	—		—		—		—		—		5		—		19		—
Industrial	—		—		—		—		—		—		—		38		—
Other commercial real estate	671		487		487		—		—		752		—		855		—
Total commercial real estate	5,003		2,975		2,975		—		—		3,375		—		4,250		—

Residential mortgage:
Permanent mortgage	29,861		24,623		24,623		—		—		24,019		315		23,739		912
Permanent mortgage guaranteed by U.S. government agencies¹	193,594		187,370		187,370		—		—		188,461		1,884		199,532		5,809
Home equity	13,332		11,992		11,992		—		—		11,880		—		11,755		—
Total residential mortgage	236,787		223,985		223,985		—		—		224,360		2,199		235,026		6,721

Personal	290		255		255		—		—		263		—		273		—

Total	$	460,466	$	404,115	$	314,610	$	89,505	$	13,284	$	415,027	$	2,199	$	417,476	$	6,721


¹	All permanent mortgage loans guaranteed by U.S. government agencies are considered impaired as we do not expect full collection of contractual principal and interest. At September 30, 2017, $8.9 million of these loans were nonaccruing and $178 million were accruing based on the guarantee by U.S. government agencies.

Generally, no interest income is recognized on impaired loans until all principal balances, including amounts charged-off, are recovered.

A summary of impaired loans at December 31, 2016 follows (in thousands):



			Recorded Investment
	Unpaid Principal Balance		Total		With No Allowance		With Allowance		Related Allowance
Commercial:
Energy	$	146,897	$	132,499	$	121,418	$	11,081	$	762
Services	11,723		8,173		8,173		—		—
Wholesale/retail	17,669		11,407		11,407		—		—
Manufacturing	5,320		4,931		4,931		—		—
Healthcare	1,147		825		825		—		—
Other commercial and industrial	29,006		21,118		21,083		35		35
Total commercial	211,762		178,953		167,837		11,116		797

Commercial real estate:
Residential construction and land development	4,951		3,433		3,433		—		—
Retail	530		326		326		—		—
Office	521		426		426		—		—
Multifamily	1,000		38		38		—		—
Industrial	76		76		76		—		—
Other commercial real estate	7,349		1,222		1,222		—		—
Total commercial real estate	14,427		5,521		5,521		—		—

Residential mortgage:
Permanent mortgage	28,830		22,855		22,809		46		46
Permanent mortgage guaranteed by U.S. government agencies¹	205,564		199,387		199,387		—		—
Home equity	12,611		11,519		11,519		—		—
Total residential mortgage	247,005		233,761		233,715		46		46

Personal	332		290		290		—		—

Total	$	473,526	$	418,525	$	407,363	$	11,162	$	843


¹	All permanent mortgage loans guaranteed by U.S. government agencies are considered impaired as we do not expect full collection of contractual principal and interest. At December 31, 2016, $12 million of these loans were nonaccruing and $188 million were accruing based on the guarantee by U.S. government agencies.

A summary of impaired loans at September 30, 2016 follows (in thousands):



											For the				For the
	As of September 30, 2016										Three Months Ended				Nine Months Ended
			Recorded Investment								September 30, 2016				September 30, 2016
	Unpaid Principal Balance		Total		With No Allowance		With Allowance		Related Allowance		Average Recorded Investment		Interest Income Recognized		Average Recorded Investment		Interest Income Recognized
Commercial:
Energy	$	179,578	$	142,966	$	100,300	$	42,666	$	6,502	$	155,555	$	—	$	85,333	$	—
Services	11,858		8,477		8,477		—		—		8,932		—		9,384		—
Wholesale/retail	8,528		2,453		2,453		—		—		2,613		—		2,686		—
Manufacturing	642		274		274		—		—		284		—		303		—
Healthcare	1,168		855		855		—		—		865		—		964		—
Other commercial and industrial	29,176		21,439		21,439		—		—		10,978		—		11,031		—
Total commercial	230,950		176,464		133,798		42,666		6,502		179,227		—		109,701		—

Commercial real estate:
Residential construction and land development	6,090		3,739		3,739		—		—		4,000		—		4,074		—
Retail	1,914		1,249		1,249		—		—		1,257		—		1,284		—
Office	1,187		882		882		—		—		744		—		766		—
Multifamily	1,000		51		51		—		—		58		—		163		—
Industrial	76		76		76		—		—		76		—		76		—
Other commercial real estate	7,375		1,353		1,353		—		—		1,430		—		1,813		—
Total commercial real estate	17,642		7,350		7,350		—		—		7,565		—		8,176		—

Residential mortgage:
Permanent mortgage	32,372		25,956		25,847		109		62		26,592		292		27,470		923
Permanent mortgage guaranteed by U.S. government agencies¹	196,162		190,309		190,309		—		—		190,547		2,098		193,879		5,893
Home equity	12,099		11,064		11,064		—		—		10,578		—		10,710		—
Total residential mortgage	240,633		227,329		227,220		109		62		227,717		2,390		232,059		6,816

Personal	724		686		686		—		—		520		—		575		—

Total	$	489,949	$	411,829	$	369,054	$	42,775	$	6,564	$	415,029	$	2,390	$	350,511	$	6,816


¹	All permanent mortgage loans guaranteed by U.S. government agencies are considered impaired as we do not expect full collection of contractual principal and interest. At September 30, 2016, $15 million of these loans were nonaccruing and $175 million were accruing based on the guarantee by U.S. government agencies.

Troubled Debt Restructurings

A summary of troubled debt restructurings ("TDRs") by accruing status as of September 30, 2017 is as follows (in thousands):



	As of September 30, 2017								Amounts Charged Off During:
	Recorded Investment		Performing in Accordance With Modified Terms		Not Performing in Accordance With Modified Terms		Specific Allowance		Three Months Ended Sept. 30, 2017		Nine Months Ended Sept. 30, 2017
Nonaccruing TDRs:

Commercial:
Energy	$	9,582	$	9,506	$	76	$	—	$	4,322	$	4,322
Services	720		103		617		—		7		10
Wholesale/retail	1,802		—		1,802		—		—		—
Manufacturing	180		180		—		—		—		—
Healthcare	—		—		—		—		—		—
Other commercial and industrial	20,097		19,890		207		—		—		—
Total commercial	32,381		29,679		2,702		—		4,329		4,332

Commercial real estate:
Residential construction and land development	327		91		236		—		—		—
Retail	289		289		—		—		—		—
Office	—		—		—		—		—		—
Multifamily	—		—		—		—		—		—
Industrial	—		—		—		—		—		—
Other commercial real estate	353		353		—		—		—		—
Total commercial real estate	969		733		236		—		—		—

Residential mortgage:
Permanent mortgage	14,765		10,188		4,577		—		—		—
Permanent mortgage guaranteed by U.S. government agencies	5,601		523		5,078		—		—		—
Home equity	5,625		4,213		1,412		—		39		70
Total residential mortgage	25,991		14,924		11,067		—		39		70

Personal	205		195		10		—		2		10

Total nonaccruing TDRs	$	59,546	$	45,531	$	14,015	$	—	$	4,370	$	4,412

Accruing TDRs:
Permanent mortgages guaranteed by U.S. government agencies	69,440		14,948		54,492		—		—		—

Total TDRs	$	128,986	$	60,479	$	68,507	$	—	$	4,370	$	4,412

A summary of troubled debt restructurings by accruing status as of December 31, 2016 is as follows (in thousands):



	As of
	December 31, 2016
	Recorded Investment		Performing in Accordance With Modified Terms		Not Performing in Accordance With Modified Terms		Specific Allowance
Nonaccruing TDRs:

Commercial:
Energy	$	16,893	$	10,867	$	6,026	$	—
Services	7,527		6,830		697		—
Wholesale/retail	11,291		11,251		40		—
Manufacturing	224		224		—		—
Healthcare	607		—		607		—
Other commercial and industrial	337		53		284		—
Total commercial	36,879		29,225		7,654		—

Commercial real estate:
Residential construction and land development	690		97		593		—
Retail	326		326		—		—
Office	143		143		—		—
Multifamily	—		—		—		—
Industrial	—		—		—		—
Other commercial real estate	548		548		—		—
Total commercial real estate	1,707		1,114		593		—

Residential mortgage:
Permanent mortgage	14,876		10,175		4,701		46
Permanent mortgage guaranteed by U.S. government agencies	6,702		2,241		4,461		—
Home equity	5,346		4,458		888		—
Total residential mortgage	26,924		16,874		10,050		46

Personal	237		236		1		—

Total nonaccuring TDRs	$	65,747	$	47,449	$	18,298	$	46

Accruing TDRs:
Permanent mortgages guaranteed by U.S. government agencies	81,370		27,289		54,081		—

Total TDRs	$	147,117	$	74,738	$	72,379	$	46

A summary of troubled debt restructurings by accruing status as of September 30, 2016 is as follows (in thousands):



	As of September 30, 2016								Amounts Charged Off During:
	Recorded Investment		Performing in Accordance With Modified Terms		Not Performing in Accordance With Modified Terms		Specific Allowance		Three Months Ended Sept. 30, 2016		Nine Months Ended Sept. 30, 2016
Nonaccruing TDRs:

Commercial:
Energy	$	1,746	$	—	$	1,746	$	—	$	500	$	1,000
Services	7,761		7,034		727		—		—		—
Wholesale/retail	2,327		2,287		40		—		—		—
Manufacturing	238		238		—		—		—		—
Healthcare	623		—		623		—		—		—
Other commercial and industrial	497		61		436		—		—		57
Total commercial	13,192		9,620		3,572		—		500		1,057

Commercial real estate:
Residential construction and land development	794		359		435		—		—		—
Retail	1,249		892		357		—		—		—
Office	149		149		—		—		—		—
Multifamily	—		—		—		—		—		—
Industrial	—		—		—		—		—		—
Other commercial real estate	666		666		—		—		—		—
Total commercial real estate	2,858		2,066		792		—		—		—

Residential mortgage:
Permanent mortgage	16,109		11,944		4,165		62		—		2
Permanent mortgage guaranteed by U.S. government agencies	8,220		2,331		5,889		—		—		—
Home equity	5,168		4,667		501		—		34		153
Total residential mortgage	29,497		18,942		10,555		62		34		155

Personal	273		271		2		—		9		18

Total nonaccruing TDRs	$	45,820	$	30,899	$	14,921	$	62	$	543	$	1,230

Accruing TDRs:
Permanent mortgages guaranteed by U.S. government agencies	80,306		29,020		51,286		—		—		—

Total TDRs	$	126,126	$	59,919	$	66,207	$	62	$	543	$	1,230

Troubled debt restructurings generally consist of interest rate concessions, payment stream concessions or a combination of concessions to distressed borrowers. The following tables detail the recorded balance of loans at September 30, 2017 by class that were restructured during the three months ended September 30, 2017 by primary type of concession (in thousands):



	Three Months Ended Sept. 30, 2017
	Accruing						Nonaccrual						Total
	Payment Stream		Combination & Other		Total		Payment Stream		Combination & Other		Total
Commercial:
Energy	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Services	—		—		—		—		—		—		—
Wholesale/retail	—		—		—		—		—		—		—
Manufacturing	—		—		—		—		—		—		—
Healthcare	—		—		—		—		—		—		—
Other commercial and industrial	—		—		—		—		60		60		60
Total commercial	—		—		—		—		60		60		60

Commercial real estate:
Residential construction and land development	—		—		—		—		—		—		—
Retail	—		—		—		—		—		—		—
Office	—		—		—		—		—		—		—
Multifamily	—		—		—		—		—		—		—
Industrial	—		—		—		—		—		—		—
Other commercial real estate	—		—		—		—		—		—		—
Total commercial real estate	—		—		—		—		—		—		—

Residential mortgage:
Permanent mortgage	—		—		—		969		506		1,475		1,475
Permanent mortgage guaranteed by U.S. government agencies	8,205		620		8,825		315		—		315		9,140
Home equity	—		—		—		—		469		469		469
Total residential mortgage	8,205		620		8,825		1,284		975		2,259		11,084

Personal	—		—		—		—		4		4		4

Total	$	8,205	$	620	$	8,825	$	1,284	$	1,039	$	2,323	$	11,148



	Nine Months Ended Sept. 30, 2017
	Accruing							Nonaccrual							Total
		Payment Stream		Combination & Other		Total			Payment Stream		Combination & Other		Total
Commercial:
Energy		$	—	$	—	$	—		$	7,781	$	—	$	7,781	$	7,781
Services		—		—		—			—		—		—		—
Wholesale/retail		—		—		—			—		—		—		—
Manufacturing		—		—		—			—		—		—		—
Healthcare		—		—		—			—		—		—		—
Other commercial and industrial		—		—		—			19,825		60		19,885		19,885
Total commercial		—		—		—			27,606		60		27,666		27,666

Commercial real estate:
Residential construction and land development		—		—		—			—		—		—		—
Retail		—		—		—			—		—		—		—
Office		—		—		—			—		—		—		—
Multifamily		—		—		—			—		—		—		—
Industrial		—		—		—			—		—		—		—
Other commercial real estate		—		—		—			—		—		—		—
Total commercial real estate		—		—		—			—		—		—		—

Residential mortgage:
Permanent mortgage		—		—		—			153		1,559		1,712		1,712
Permanent mortgage guaranteed by U.S. government agencies		18,678		2,649		21,327			443		85		528		21,855
Home equity		—		—		—			104		1,468		1,572		1,572
Total residential mortgage		18,678		2,649		21,327			700		3,112		3,812		25,139

Personal		—		—		—			—		48		48		48

Total		$	18,678	$	2,649	$	21,327		$	28,306	$	3,220	$	31,526	$	52,853

Troubled debt restructurings generally consist of interest rate concessions, payment stream concessions or a combination of concessions to distressed borrowers. The following tables detail the recorded balance of loans by class that were restructured during three months ended September 30, 2016 by primary type of concession (in thousands):



	Three Months Ended Sept. 30, 2016
	Accruing						Nonaccrual						Total
	Payment Stream		Combination & Other		Total		Payment Stream		Combination & Other		Total
Commercial:
Energy	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Services	—		—		—		—		—		—		—
Wholesale/retail	—		—		—		—		—		—		—
Manufacturing	—		—		—		—		—		—		—
Healthcare	—		—		—		—		—		—		—
Other commercial and industrial	—		—		—		—		—		—		—
Total commercial	—		—		—		—		—		—		—

Commercial real estate:
Residential construction and land development	—		—		—		—		—		—		—
Retail	—		—		—		—		—		—		—
Office	—		—		—		—		—		—		—
Multifamily	—		—		—		—		—		—		—
Industrial	—		—		—		—		—		—		—
Other commercial real estate	—		—		—		—		—		—		—
Total commercial real estate	—		—		—		—		—		—		—

Residential mortgage:
Permanent mortgage	—		—		—		—		151		151		151
Permanent mortgage guaranteed by U.S. government agencies	3,527		4,211		7,738		—		287		287		8,025
Home equity	—		—		—		—		920		920		920
Total residential mortgage	3,527		4,211		7,738		—		1,358		1,358		9,096

Personal	—		—		—		—		19		19		19

Total	$	3,527	$	4,211	$	7,738	$	—	$	1,377	$	1,377	$	9,115



	Nine Months Ended Sept. 30, 2016
	Accruing						Nonaccrual						Total
	Payment Stream		Combination & Other		Total		Payment Stream		Combination & Other		Total
Commercial:
Energy	$	—	$	—	$	—	$	501	$	—	$	501	$	501
Services	—		—		—		—		—		—		—
Wholesale/retail	—		—		—		—		—		—		—
Manufacturing	—		—		—		—		—		—		—
Healthcare	—		—		—		—		—		—		—
Other commercial and industrial	—		—		—		—		—		—		—
Total commercial	—		—		—		501		—		501		501

Commercial real estate:
Residential construction and land development	—		—		—		—		—		—		—
Retail	—		—		—		—		—		—		—
Office	—		—		—		—		—		—		—
Multifamily	—		—		—		—		—		—		—
Industrial	—		—		—		—		—		—		—
Other commercial real estate	—		—		—		—		—		—		—
Total commercial real estate	—		—		—		—		—		—		—

Residential mortgage:
Permanent mortgage	—		—		—		1,037		1,051		2,088		2,088
Permanent mortgage guaranteed by U.S. government agencies	9,687		9,350		19,037		—		982		982		20,019
Home equity	—		—		—		48		1,630		1,678		1,678
Total residential mortgage	9,687		9,350		19,037		1,085		3,663		4,748		23,785

Personal	—		—		—		—		82		82		82

Total	$	9,687	$	9,350	$	19,037	$	1,586	$	3,745	$	5,331	$	24,368

The following table summarizes, by loan class, the recorded investment at September 30, 2017 and 2016, respectively, of loans modified as TDRs within the previous 12 months and for which there was a payment default during the three months ended September 30, 2017 and 2016, respectively (in thousands):



	Three Months Ended Sept. 30, 2017						Nine Months Ended Sept. 30, 2017
	Accruing		Nonaccrual		Total		Accruing		Nonaccrual		Total
Commercial:
Energy	$	—	$	7,857	$	7,857	$	—	$	9,582	$	9,582
Services	—		—		—		—		—		—
Wholesale/retail	—		—		—		—		—		—
Manufacturing	—		—		—		—		—		—
Healthcare	—		—		—		—		—		—
Other commercial and industrial	—		—		—		—		19,825		19,825
Total commercial	—		7,857		7,857		—		29,407		29,407

Commercial real estate:
Residential construction and land development	—		—		—		—		—		—
Retail	—		—		—		—		—		—
Office	—		—		—		—		—		—
Multifamily	—		—		—		—		—		—
Industrial	—		—		—		—		—		—
Other commercial real estate	—		—		—		—		—		—
Total commercial real estate	—		—		—		—		—		—

Residential mortgage:
Permanent mortgage	—		1,511		1,511		—		1,511		1,511
Permanent mortgage guaranteed by U.S. government agencies	23,620		878		24,498		24,349		878		25,227
Home equity	—		1,030		1,030		—		1,139		1,139
Total residential mortgage	23,620		3,419		27,039		24,349		3,528		27,877

Personal	—		10		10		—		10		10

Total	$	23,620	$	11,286	$	34,906	$	24,349	$	32,945	$	57,294

A payment default is defined as being 30 days or more past due. The table above includes loans that experienced a payment default during the period, but may be performing in accordance with the modified terms as of the balance sheet date.



	Three Months Ended Sept. 30, 2016						Nine Months Ended Sept. 30, 2016
	Accruing		Nonaccrual		Total		Accruing		Nonaccrual		Total
Commercial:
Energy	$	—	$	1,746	$	1,746	$	—	$	1,746	$	1,746
Services	—		—		—		—		—		—
Wholesale/retail	—		—		—		—		—		—
Manufacturing	—		—		—		—		—		—
Healthcare	—		—		—		—		—		—
Other commercial and industrial	—		—		—		—		—		—
Total commercial	—		1,746		1,746		—		1,746		1,746

Commercial real estate:
Residential construction and land development	—		—		—		—		—		—
Retail	—		—		—		—		—		—
Office	—		—		—		—		—		—
Multifamily	—		—		—		—		—		—
Industrial	—		—		—		—		—		—
Other commercial real estate	—		—		—		—		—		—
Total commercial real estate	—		—		—		—		—		—

Residential mortgage:
Permanent mortgage	—		298		298		—		542		542
Permanent mortgage guaranteed by U.S. government agencies	17,491		1,095		18,586		19,352		1,121		20,473
Home equity	—		258		258		—		258		258
Total residential mortgage	17,491		1,651		19,142		19,352		1,921		21,273

Personal	—		11		11		—		11		11

Total	$	17,491	$	3,408	$	20,899	$	19,352	$	3,678	$	23,030

Nonaccrual & Past Due Loans

Past due status for all loan classes is based on the actual number of days since the last payment was due according to the contractual terms of the loans.

A summary of loans currently performing, loans past due and accruing and nonaccrual loans as of September 30, 2017 is as follows (in thousands):



			Past Due
	Current		30 to 59 Days		60 to 89 Days		90 Days or More		Nonaccrual		Total
Commercial:
Energy	$	2,752,259	$	—	$	5,039	$	—	$	110,683	$	2,867,981
Services	2,963,746		2,343		250		—		1,174		2,967,513
Wholesale/retail	1,654,018		1,748		409		30		1,893		1,658,098
Manufacturing	508,231		—		2,156		—		9,059		519,446
Healthcare	2,214,849		156		—		—		24,446		2,239,451
Other commercial and industrial	513,748		52		—		—		29,645		543,445
Total commercial	10,606,851		4,299		7,854		30		176,900		10,795,934

Commercial real estate:
Residential construction and land development	109,994		184		—		—		1,924		112,102
Retail	724,850		726		—		—		289		725,865
Office	796,687		127		—		—		275		797,089
Multifamily	999,009		—		—		—		—		999,009
Industrial	591,080		—		—		—		—		591,080
Other commercial real estate	292,322		1		—		187		487		292,997
Total commercial real estate	3,513,942		1,038		—		187		2,975		3,518,142

Residential mortgage:
Permanent mortgage	985,183		3,705		454		—		24,623		1,013,965
Permanent mortgages guaranteed by U.S. government agencies	25,169		17,346		13,343		122,621		8,891		187,370
Home equity	728,884		3,066		445		28		11,992		744,415
Total residential mortgage	1,739,236		24,117		14,242		122,649		45,506		1,945,750

Personal	943,368		3,296		81		8		255		947,008

Total	$	16,803,397	$	32,750	$	22,177	$	122,874	$	225,636	$	17,206,834

A summary of loans currently performing, loans past due and accruing and nonaccrual loans as of December 31, 2016 is as follows (in thousands):



			Past Due
	Current		30 to 59 Days		60 to 89 Days	90 Days or More		Nonaccrual		Total
Commercial:
Energy	$	2,364,890	$	479	—	$	—	$	132,499	$	2,497,868
Services	3,099,605		191		1,021	—		8,173		3,108,990
Wholesale/retail	1,561,650		3,761		—	—		11,407		1,576,818
Manufacturing	509,662		382		—	—		4,931		514,975
Healthcare	2,201,050		—		41	—		825		2,201,916
Other commercial and industrial	468,981		155		3	—		21,118		490,257
Total commercial	10,205,838		4,968		1,065	—		178,953		10,390,824

Commercial real estate:
Residential construction and land development	132,100		—		—	—		3,433		135,533
Retail	761,562		—		—	—		326		761,888
Office	798,462		—		—	—		426		798,888
Multifamily	903,234		—		—	—		38		903,272
Industrial	871,673		—		—	—		76		871,749
Other commercial real estate	336,488		6		—	—		1,222		337,716
Total commercial real estate	3,803,519		6		—	—		5,521		3,809,046

Residential mortgage:
Permanent mortgage	979,386		3,299		1,280	—		22,855		1,006,820
Permanent mortgages guaranteed by U.S. government agencies	40,594		17,465		13,803	115,679		11,846		199,387
Home equity	729,493		2,276		337	—		11,519		743,625
Total residential mortgage	1,749,473		23,040		15,420	115,679		46,220		1,949,832

Personal	838,811		589		263	5		290		839,958

Total	$	16,597,641	$	28,603	16,748	$	115,684	$	230,984	$	16,989,660

A summary of loans currently performing, loans past due and accruing and nonaccrual loans as of September 30, 2016 is as follows (in thousands):



			Past Due
	Current		30 to 59 Days		60 to 89 Days	90 Days or More		Nonaccrual		Total
Commercial:
Energy	$	2,365,850	$	11,988	—	$	—	$	142,966	$	2,520,804
Services	2,923,874		502		39	3,707		8,477		2,936,599
Wholesale/retail	1,599,356		221		—	—		2,453		1,602,030
Manufacturing	499,212		—		—	—		274		499,486
Healthcare	2,083,556		635		—	—		855		2,085,046
Other commercial and industrial	454,538		34		68	119		21,439		476,198
Total commercial	9,926,386		13,380		107	3,826		176,464		10,120,163

Commercial real estate:
Residential construction and land development	156,207		—		—	—		3,739		159,946
Retail	796,362		3,766		—	—		1,249		801,377
Office	751,823		—		—	—		882		752,705
Multifamily	868,591		—		5,131	—		51		873,773
Industrial	837,945		—		—	—		76		838,021
Other commercial real estate	366,416		7		—	—		1,353		367,776
Total commercial real estate	3,777,344		3,773		5,131	—		7,350		3,793,598

Residential mortgage:
Permanent mortgage	939,853		3,547		202	—		25,956		969,558
Permanent mortgages guaranteed by U.S. government agencies	41,150		17,364		12,963	103,400		15,432		190,309
Home equity	700,031		1,526		305	—		11,064		712,926
Total residential mortgage	1,681,034		22,437		13,470	103,400		52,452		1,872,793

Personal	677,194		191		148	13		686		678,232

Total	$	16,061,958	$	39,781	18,856	$	107,239	$	236,952	$	16,464,786