The following is a summary of acquired non-credit impaired loans accounted for under FASB ASC Topic 310-20, net of related discount:

The unamortized discount related to the acquired non-credit impaired loans totaled $24.2 million, $33.4 million, and $37.1 million at September 30, 2019, December 31, 2018, and September 30, 2018, respectively.

In accordance with FASB ASC Topic 310-30, we aggregated acquired loans that have common risk characteristics into pools of loan categories as described in the table below. The following is a summary of acquired credit impaired loans accounted for under FASB ASC Topic 310-30 (identified as credit impaired at the time of acquisition), net of related discount:

Contractual loan payments receivable, estimates of amounts not expected to be collected, other fair value adjustments and the resulting carrying values of acquired credit impaired loans as of September 30, 2019, December 31, 2018 and September 30, 2018 are as follows:

Income on acquired credit impaired loans that are not impaired at the acquisition date is recognized in the same manner as loans impaired at the acquisition date. A portion of the fair value discount on acquired non-impaired loans has been ascribed as an accretable yield that is accreted into interest income over the estimated remaining life of the loans. The remaining nonaccretable difference represents cash flows not expected to be collected.

The following are changes in the carrying value of acquired credit impaired loans:

The table below reflects refined accretable yield balance for acquired credit impaired loans:

The table above reflects the changes in the carrying amount of accretable yield for the acquired credit impaired loans and shows both the contractual interest income and incremental accretion for the nine months ended September 30, 2019 and 2018. In the first nine months of 2019, the accretable yield balance declined by $26.6 million as total contractual interest and accretion income of $35.5 million was recognized. This was partially offset by improved expected cash flows of $9.0 million. The improved cash flows for the prior year was adjusted to accurately reflect the split between income types.

As of September 30, 2019, the table above excludes $2.0 billion ($2.0 billion in contractual principal less a $24.2 million discount) in acquired loans which are accounted for under FASB ASC Topic 310-20. These loans were identified as either performing with no discount related to credit quality or as revolving lines of credit (commercial or consumer) at acquisition. As of September 30, 2018, the balance of these acquired loans totaled $2.8 billion ($2.8 billion in contractual principal less a $37.1 million remaining discount).

Our loan loss policy adheres to GAAP as well as interagency guidance. The allowance for loan losses, which we sometimes refer to herein as ALLL, is based upon estimates made by management. We maintain an allowance for loan losses at a level that we believe is appropriate to cover estimated credit losses on individually evaluated loans that are determined to be impaired as well as estimated credit losses inherent in the remainder of our loan portfolio. Arriving at the allowance involves a high degree of management judgment and results in a range of estimated losses. We regularly evaluate the adequacy of the allowance through our internal risk rating system, outside credit review, and regulatory agency examinations to assess the quality of the loan portfolio and identify problem loans. The evaluation process also includes our analysis of current economic conditions, composition of the loan portfolio, past due and nonaccrual loans, concentrations of credit, lending policies and procedures, and historical loan loss experience. While management uses available information to recognize losses on loans, future additions to the allowance may be necessary based on, among other factors, changes in economic conditions in our markets. In addition, regulatory agencies, as an integral part of their examination process, periodically review our allowances for losses on loans. These agencies may require management to recognize additions to the allowances based on their judgments about information available to them at the time of their examination. Because of these and other factors, it is possible that the allowances for losses on loans may change. The provision for loan losses is charged to expense in an amount necessary to maintain the allowance at an appropriate level.

The allowance for loan losses on non-acquired loans consists of general and specific reserves. The general reserves are determined by applying loss percentages to the portfolio that are based on historical loss experience for each class of loans and management’s evaluation and “risk grading” of the loan portfolio. Additionally, the general economic and business conditions affecting key lending areas, credit quality trends, collateral values, loan volumes and concentrations, seasoning of the loan portfolio, the findings of internal and external credit reviews and results from external bank regulatory examinations are included in this evaluation. Currently, these adjustments are applied to the non-acquired loan portfolio when estimating the level of reserve required. The specific reserves are determined on a loan-by-loan basis based on management’s evaluation of our exposure for each credit, given the current payment status of the loan and the value of any underlying collateral. These are loans classified by management as doubtful or substandard. For such loans that are also classified as impaired, an allowance is established when the discounted cash flows (or collateral value or observable market price) of the impaired loan is lower than the carrying value of that loan. Generally, the need for specific reserve is evaluated on impaired loans, and once a specific reserve is established for a loan, a charge off of that amount occurs in the quarter subsequent to the establishment of the specific reserve. Loans that are determined to be impaired are provided a specific reserve, if necessary, and are excluded from the calculation of the general reserves.

Beginning with the First Financial Holdings, Inc. acquisition, we segregated the loan portfolio into performing loans (“non-credit impaired) and purchased credit impaired loans. The performing loans and revolving type loans are accounted for under FASB ASC 310-20, with each loan being accounted for individually. The allowance for loan losses on these loans will be measured and recorded consistent with non-acquired loans. The acquired credit impaired loans will follow the description in the next paragraph.

In determining the acquisition date fair value of purchased loans, and in subsequent accounting, we generally aggregate purchased loans into pools of loans with common risk characteristics. Expected cash flows at the acquisition date in excess of the fair value of loans are recorded as interest income over the life of the loans using a level yield method if the timing and amount of the future cash flows of the pool is reasonably estimable. Subsequent to the acquisition date, increases in cash flows over those expected at the acquisition date are reclassified from the

non-accretable difference to accretable yield and recognized as interest income prospectively. Decreases in expected cash flows after the acquisition date are recognized by recording an allowance for loan losses. Management analyzes the acquired loan pools using various assessments of risk to determine an expected loss. The expected loss is derived based upon a loss given default based upon the collateral type and/or detailed review by loan officers and the probability of default that is determined based upon historical data at the loan level. All acquired loans managed by Special Asset Management are reviewed quarterly and assigned a loss given default. Acquired loans not managed by Special Asset Management are reviewed twice a year in a similar method to our originated portfolio of loans which follow review thresholds based on risk rating categories. In the fourth quarter of 2015, we modified its methodology to a more granular approach in determining loss given default on substandard loans with a net book balance between $100,000 and $500,000 by adjusting the loss given default to 90% of the most current collateral valuation based on appraised value. Substandard loans greater than $500,000 were individually assigned loss given defaults each quarter. Trends are reviewed in terms of accrual status, past due status, and weighted-average grade of the loans within each of the accounting pools. In addition, the relationship between the change in the unpaid principal balance and change in the mark is assessed to correlate the directional consistency of the expected loss for each pool.

An aggregated analysis of the changes in allowance for loan losses is as follows:

(1)	– Recoveries related to acquired credit impaired loans are recorded through other noninterest income on the consolidated statement of income and do not run through the ALLL.

The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for non-acquired loans:


	Construction		Commercial		Commercial		Consumer						Other Income
	& Land		Non-owner		Owner		Owner		Home		Commercial		Producing				Other
(Dollars in thousands)	Development		Occupied		Occupied		Occupied		Equity		& Industrial		Property		Consumer		Loans		Total
Three Months Ended September 30, 2019
Allowance for loan losses:
Balance, June 30, 2019	$	5,718	$	10,311	$	9,526	$	12,432	$	3,177	$	7,495	$	1,359	$	3,572	$	—	$	53,590
Charge-offs		(69)		—		(31)		(10)		(100)		(32)		—		(1,727)		—		(1,969)
Recoveries		208		2		18		149		86		77		29		265		—		834
Provision (benefit)		159		238		456		(24)		28		21		(29)		1,633		—		2,482
Balance, September 30, 2019	$	6,016	$	10,551	$	9,969	$	12,547	$	3,191	$	7,561	$	1,359	$	3,743	$	—	$	54,937
Loans individually evaluated for impairment	$	587	$	—	$	33	$	33	$	121	$	387	$	58	$	2	$	—	$	1,221
Loans collectively evaluated for impairment	$	5,429	$	10,551	$	9,936	$	12,514	$	3,070	$	7,174	$	1,301	$	3,741	$	—	$	53,716
Loans:
Loans individually evaluated for impairment	$	32,673	$	87	$	7,135	$	5,127	$	2,345	$	5,313	$	2,096	$	91	$	—	$	54,867
Loans collectively evaluated for impairment		922,645		1,777,240		1,670,560		2,113,000		519,399		1,125,534		218,861		524,949		1,457		8,873,645
Total non-acquired loans	$	955,318	$	1,777,327	$	1,677,695	$	2,118,127	$	521,744	$	1,130,847	$	220,957	$	525,040	$	1,457	$	8,928,512
Three Months Ended September 30, 2018
Allowance for loan losses:
Balance, June 30, 2018	$	6,187	$	7,209	$	8,607	$	10,945	$	3,368	$	6,711	$	1,413	$	3,071	$	363	$	47,874
Charge-offs		—		—		(578)		(76)		(40)		(34)		—		(1,163)		—		(1,891)
Recoveries		178		2		105		43		11		27		3		186		—		555
Provision (benefit)		(352)		774		943		468		102		219		(6)		1,089		94		3,331
Balance, September 30, 2018	$	6,013	$	7,985	$	9,077	$	11,380	$	3,441	$	6,923	$	1,410	$	3,183	$	457	$	49,869
Loans individually evaluated for impairment	$	723	$	81	$	40	$	28	$	171	$	475	$	133	$	6	$	—	$	1,657
Loans collectively evaluated for impairment	$	5,290	$	7,904	$	9,037	$	11,352	$	3,270	$	6,448	$	1,277	$	3,177	$	457	$	48,212
Loans:
Loans individually evaluated for impairment	$	35,776	$	1,315	$	4,551	$	5,420	$	3,026	$	1,409	$	2,930	$	213	$	—	$	54,640
Loans collectively evaluated for impairment		867,060		1,278,013		1,444,518		1,838,783		470,355		990,433		207,053		438,576		17,047		7,551,838
Total non-acquired loans	$	902,836	$	1,279,328	$	1,449,069	$	1,844,203	$	473,381	$	991,842	$	209,983	$	438,789	$	17,047	$	7,606,478


	Construction		Commercial		Commercial		Consumer						Other Income
	& Land		Non-owner		Owner		Owner		Home		Commercial		Producing				Other
(Dollars in thousands)	Development		Occupied		Occupied		Occupied		Equity		& Industrial		Property		Consumer		Loans		Total
Nine Months Ended September 30, 2019
Allowance for loan losses:
Balance, December 31, 2018	$	5,682	$	8,754	$	9,369	$	11,913	$	3,434	$	7,454	$	1,446	$	3,101	$	41	$	51,194
Charge-offs		(78)		(3)		(43)		(95)		(115)		(141)		(31)		(4,035)		—		(4,541)
Recoveries		833		47		84		181		220		286		87		723		—		2,461
Provision (benefit)		(421)		1,753		559		548		(348)		(38)		(143)		3,954		(41)		5,823
Balance, September 30, 2019	$	6,016	$	10,551	$	9,969	$	12,547	$	3,191	$	7,561	$	1,359	$	3,743	$	—	$	54,937
Nine Months Ended September 30, 2018
Allowance for loan losses:
Balance, December 31, 2017	$	5,921	$	6,525	$	8,128	$	9,668	$	3,250	$	5,488	$	1,375	$	2,788	$	305	$	43,448
Charge-offs		(35)		—		(659)		(80)		(111)		(178)		—		(3,237)		—		(4,300)
Recoveries		1,167		6		76		169		139		241		14		596		—		2,408
Provision (benefit)		(1,040)		1,454		1,532		1,623		163		1,372		21		3,036		152		8,313
Balance, September 30, 2018	$	6,013	$	7,985	$	9,077	$	11,380	$	3,441	$	6,923	$	1,410	$	3,183	$	457	$	49,869

The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for acquired non-credit impaired loans:


	Construction		Commercial		Commercial		Consumer						Other Income
	& Land		Non-owner		Owner		Owner		Home		Commercial		Producing
(Dollars in thousands)	Development		Occupied		Occupied		Occupied		Equity		& Industrial		Property		Consumer		Total
Three Months Ended September 30, 2019
Allowance for loan losses:
Balance at beginning of period	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Charge-offs		(39)		—		—		—		(23)		(648)		—		(100)		(810)
Recoveries		1		—		—		21		9		10		—		9		50
Provision (benefit)		38		—		—		(21)		14		638		—		91		760
Balance, September 30, 2019	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—

Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—

Loans:
Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment		53,302		503,443		345,040		543,432		198,112		126,092		103,093		93,089		1,965,603
Total acquired non-credit impaired loans	$	53,302	$	503,443	$	345,040	$	543,432	$	198,112	$	126,092	$	103,093	$	93,089	$	1,965,603

Three Months Ended September 30, 2018
Allowance for loan losses:
Balance at beginning of period	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Charge-offs		—		—		—		—		(4)		(30)		—		(63)		(97)
Recoveries		1		—		—		1		6		5		—		14		27
Provision (benefit)		(1)		—		—		(1)		(2)		25		—		49		70
Balance, September 30, 2018	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—

Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—

Loans:
Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment		222,562		684,793		455,803		647,064		259,558		247,922		150,371		118,029		2,786,102
Total acquired non-credit impaired loans	$	222,562	$	684,793	$	455,803	$	647,064	$	259,558	$	247,922	$	150,371	$	118,029	$	2,786,102


	Construction		Commercial		Commercial		Consumer						Other Income
	& Land		Non-owner		Owner		Owner		Home		Commercial		Producing
(Dollars in thousands)	Development		Occupied		Occupied		Occupied		Equity		& Industrial		Property		Consumer		Total
Nine Months Ended September 30, 2019
Allowance for loan losses:
Balance, December 31, 2018	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Charge-offs		(45)		—		(786)		(6)		(263)		(1,288)		(26)		(305)		(2,719)
Recoveries		3		—		—		26		55		181		71		36		372
Provision (benefit)		42		—		786		(20)		208		1,107		(45)		269		2,347
Balance, September 30, 2019	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Nine Months Ended September 30, 2018
Allowance for loan losses:
Balance, December 31, 2017	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—
Charge-offs		(106)		—		(28)		(70)		(244)		(838)		—		(328)		(1,614)
Recoveries		8		—		—		63		85		60		—		63		279
Provision (benefit)		98		—		28		7		159		778		—		265		1,335
Balance, September 30, 2018	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—	$	—

The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for acquired credit impaired loans:


			Commercial
			Real Estate-
	Commercial		Construction and		Residential				Commercial
(Dollars in thousands)	Real Estate		Development		Real Estate		Consumer		and Industrial		Total
Three Months Ended September 30, 2019
Allowance for loan losses:
Balance, June 30, 2019	$	1,009	$	798	$	2,346	$	470	$	—	$	4,623
Provision (benefit) for loan losses		386		(38)		447		(9)		—		786
Reduction due to loan removals		—		—		(91)		—		—		(91)
Balance, September 30, 2019	$	1,395	$	760	$	2,702	$	461	$	—	$	5,318
Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment	$	1,395	$	760	$	2,702	$	461	$	—	$	5,318
Loans:*
Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment		149,134		26,930		175,044		36,812		8,112		396,032
Total acquired credit impaired loans	$	149,134	$	26,930	$	175,044	$	36,812	$	8,112	$	396,032

Three Months Ended September 30, 2018
Allowance for loan losses:
Balance , June 30, 2018	$	636	$	576	$	2,514	$	572	$	128	$	4,426
Provision (benefit) for loan losses		62		(205)		(87)		(26)		(28)		(284)
Reduction due to loan removals		(6)		(31)		(116)		—		(21)		(174)
Balance, September 30, 2018	$	692	$	340	$	2,311	$	546	$	79	$	3,968
Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment	$	692	$	340	$	2,311	$	546	$	79	$	3,968
Loans:*
Loans individually evaluated for impairment	$	—	$	—	$	—	$	—	$	—	$	—
Loans collectively evaluated for impairment		209,518		34,312		218,019		44,081		10,671		516,601
Total acquired credit impaired loans	$	209,518	$	34,312	$	218,019	$	44,081	$	10,671	$	516,601


			Commercial
			Real Estate-
	Commercial		Construction and		Residential				Commercial
(Dollars in thousands)	Real Estate		Development		Real Estate		Consumer		and Industrial		Total
Nine Months Ended September 30, 2019
Allowance for loan losses:
Balance, December 31, 2018	$	801	$	717	$	2,246	$	761	$	79	$	4,604
Provision (benefit) for loan losses		599		43		742		(300)		(34)		1,050
Reduction due to loan removals		(5)		—		(286)		—		(45)		(336)
Balance, September 30, 2019	$	1,395	$	760	$	2,702	$	461	$	—	$	5,318
Nine Months Ended September 30, 2018
Allowance for loan losses:
Balance, December 31, 2017	$	288	$	180	$	3,553	$	461	$	145	$	4,627
Provision (benefit) for loan losses		423		273		(894)		88		511		401
Reduction due to loan removals		(19)		(113)		(348)		(3)		(577)		(1,060)
Balance, September 30, 2018	$	692	$	340	$	2,311	$	546	$	79	$	3,968

*— The carrying value of acquired credit impaired loans includes a non-accretable difference which is primarily associated with the assessment of credit quality of acquired loans.

As part of the ongoing monitoring of the credit quality of our loan portfolio, management tracks certain credit quality indicators, including trends related to (i) the level of classified loans, (ii) net charge-offs, (iii) non-performing loans (see details below), and (iv) the general economic conditions of the markets that we serve.

We utilize a risk grading matrix to assign a risk grade to each of its loans. A description of the general characteristics of the risk grades is as follows:

●

Pass—These loans range from minimal credit risk to average, however, still acceptable credit risk.

●

Special mention—A special mention loan has potential weaknesses that deserve management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the loan or the institution’s credit position at some future date.

●

Substandard—A substandard loan is inadequately protected by the current sound worth and paying capacity of the obligor or of the collateral pledged, if any. Loans so classified must have a well-defined weakness, or weaknesses, that may jeopardize the liquidation of the debt. A substandard loan is characterized by the distinct possibility that the Bank will sustain some loss if the deficiencies are not corrected.

●

Doubtful—A doubtful loan has all of the weaknesses inherent in one classified as substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of the currently existing facts, conditions and values, highly questionable and improbable.

The following table presents the credit risk profile by risk grade of commercial loans for non-acquired loans:


	Construction & Development						Commercial Non-owner Occupied						Commercial Owner Occupied
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	947,230	$	832,612	$	889,818	$	1,768,013	$	1,407,744	$	1,270,557	$	1,648,456	$	1,480,267	$	1,421,090
Special mention		5,601		6,015		9,906		7,091		6,427		7,027		17,319		24,576		18,337
Substandard		2,487		2,818		3,112		2,223		1,380		1,744		11,920		12,708		9,642
Doubtful		—		—		—		—		—		—		—		—		—
	$	955,318	$	841,445	$	902,836	$	1,777,327	$	1,415,551	$	1,279,328	$	1,677,695	$	1,517,551	$	1,449,069


	Commercial & Industrial						Other Income Producing Property						Commercial Total
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	1,103,532	$	1,037,915	$	970,586	$	215,624	$	208,186	$	203,844	$	5,682,855	$	4,966,724	$	4,755,895
Special mention		18,148		5,887		12,997		3,922		4,706		4,671		52,081		47,611		52,938
Substandard		9,167		11,150		8,259		1,411		1,461		1,468		27,208		29,517		24,225
Doubtful		—		—		—		—		—		—		—		—		—
	$	1,130,847	$	1,054,952	$	991,842	$	220,957	$	214,353	$	209,983	$	5,762,144	$	5,043,852	$	4,833,058

The following table presents the credit risk profile by risk grade of consumer loans for non-acquired loans:


	Consumer Owner Occupied						Home Equity						Consumer
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	2,091,129	$	1,909,427	$	1,816,735	$	510,508	$	481,607	$	460,720	$	522,674	$	446,823	$	437,043
Special mention		9,054		11,304		11,614		5,373		7,293		6,037		421		437		517
Substandard		17,944		15,534		15,854		5,863		6,248		6,624		1,945		1,404		1,229
Doubtful		—		—		—		—		—		—		—		—		—
	$	2,118,127	$	1,936,265	$	1,844,203	$	521,744	$	495,148	$	473,381	$	525,040	$	448,664	$	438,789


	Other						Consumer Total
	September 30, 2019		December 31, 2018		September 30, 2018		September 30, 2019		December 31, 2018		September 30, 2018
Pass	$	1,457	$	9,357	$	17,047	$	3,125,768	$	2,847,214	$	2,731,545
Special mention		—		—		—		14,848		19,034		18,168
Substandard		—		—		—		25,752		23,186		23,707
Doubtful		—		—		—		—		—		—
	$	1,457	$	9,357	$	17,047	$	3,166,368	$	2,889,434	$	2,773,420

The following table presents the credit risk profile by risk grade of total non-acquired loans:


	Total Non-acquired Loans
	September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018
Pass	$	8,808,623	$	7,813,938	$	7,487,440
Special mention		66,929		66,645		71,106
Substandard		52,960		52,703		47,932
Doubtful		—		—		—
	$	8,928,512	$	7,933,286	$	7,606,478

The following table presents the credit risk profile by risk grade of commercial loans for acquired non-credit impaired loans:


							Commercial Non-owner
	Construction & Development						Occupied						Commercial Owner Occupied
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	51,340	$	163,777	$	221,034	$	492,258	$	665,913	$	670,176	$	330,005	$	411,783	$	447,877
Special mention		736		838		921		5,035		13,018		14,612		3,427		5,664		6,933
Substandard		1,226		455		607		6,150		322		5		11,608		4,394		993
Doubtful		—		—		—		—		—		—		—		—		—
	$	53,302	$	165,070	$	222,562	$	503,443	$	679,253	$	684,793	$	345,040	$	421,841	$	455,803


							Other Income Producing
	Commercial & Industrial						Property						Commercial Total
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	120,926	$	202,399	$	239,906	$	95,611	$	125,399	$	143,349	$	1,090,140	$	1,569,271	$	1,722,342
Special mention		4,051		6,523		7,634		5,937		6,419		6,208		19,186		32,462		36,308
Substandard		1,115		3,615		382		1,545		1,292		814		21,644		10,078		2,801
Doubtful		—		—		—		—		—		—		—		—		—
	$	126,092	$	212,537	$	247,922	$	103,093	$	133,110	$	150,371	$	1,130,970	$	1,611,811	$	1,761,451

The following table presents the credit risk profile by risk grade of consumer loans for acquired non-credit impaired loans:


	Consumer Owner Occupied						Home Equity						Consumer
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	532,760	$	617,391	$	635,443	$	184,946	$	227,515	$	244,017	$	90,076	$	108,833	$	115,154
Special mention		6,805		7,868		7,412		5,405		7,688		8,089		574		698		619
Substandard		3,867		3,554		4,209		7,761		7,222		7,452		2,439		2,246		2,256
Doubtful		—		—		—		—		—		—		—		—		—
	$	543,432	$	628,813	$	647,064	$	198,112	$	242,425	$	259,558	$	93,089	$	111,777	$	118,029


	Consumer Total
	September 30,		December 31,		September 30,
	2019		2018		2018
Pass	$	807,782	$	953,739	$	994,614
Special mention		12,784		16,254		16,120
Substandard		14,067		13,022		13,917
Doubtful		—		—		—
	$	834,633	$	983,015	$	1,024,651

The following table presents the credit risk profile by risk grade of total acquired non-credit impaired loans:


	Total Acquired
	Non-credit Impaired Loans
	September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018
Pass	$	1,897,922	$	2,523,010	$	2,716,956
Special mention		31,970		48,716		52,428
Substandard		35,711		23,100		16,718
Doubtful		—		—		—
	$	1,965,603	$	2,594,826	$	2,786,102

The following table presents the credit risk profile by risk grade of acquired credit impaired loans (identified as credit-impaired at the time of acquisition), net of the related discount (this table should be read in conjunction with the allowance for acquired credit impaired loan losses table found on page 27):


							Commercial Real Estate—
							Construction and
	Commercial Real Estate						Development
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018		2019		2018		2018
Pass	$	121,264	$	160,788	$	164,435	$	18,978	$	20,293	$	20,796
Special mention		9,064		14,393		22,629		3,018		3,001		3,165
Substandard		18,806		21,583		22,454		4,934		9,648		10,351
Doubtful		—		—		—		—		—		—
	$	149,134	$	196,764	$	209,518	$	26,930	$	32,942	$	34,312


	Residential Real Estate						Consumer						Commercial & Industrial
	September 30,		December 31,		September 30,		September 30,		December 31,		September 30,		September 30,		December 31,		September 30,
	2019		2018		2018		2019		2018		2018		2019		2018		2018
Pass	$	88,131	$	104,181	$	109,004	$	4,696	$	5,751	$	5,927	$	5,703	$	5,093	$	5,514
Special mention		36,901		41,964		42,834		12,723		14,484		14,795		471		546		584
Substandard		50,012		61,337		66,181		19,393		22,257		23,359		1,938		4,404		4,573
Doubtful		—		—		—		—		—		—		—		—		—
	$	175,044	$	207,482	$	218,019	$	36,812	$	42,492	$	44,081	$	8,112	$	10,043	$	10,671


	Total Acquired
	Credit Impaired Loans
	September 30,		December 31,		September 30,
	2019		2018		2018
Pass	$	238,772	$	296,106	$	305,676
Special mention		62,177		74,388		84,007
Substandard		95,083		119,229		126,918
Doubtful		—		—		—
	$	396,032	$	489,723	$	516,601

The risk grading of acquired credit impaired loans is determined utilizing a loan’s contractual balance, while the amount recorded in the financial statements and reflected above is the carrying value.

The following table presents an aging analysis of past due loans (includes nonaccrual loans), segregated by class for non-acquired loans:


	30 - 59 Days		60 - 89 Days		90+ Days		Total				Total
(Dollars in thousands)	Past Due		Past Due		Past Due		Past Due		Current		Loans
September 30, 2019
Commercial real estate:
Construction and land development	$	194	$	17	$	323	$	534	$	954,784	$	955,318
Commercial non-owner occupied		173		—		299		472		1,776,855		1,777,327
Commercial owner occupied		2,914		1,662		2,776		7,352		1,670,343		1,677,695
Consumer real estate:
Consumer owner occupied		1,610		569		2,271		4,450		2,113,677		2,118,127
Home equity loans		478		368		183		1,029		520,715		521,744
Commercial and industrial		1,219		480		1,525		3,224		1,127,623		1,130,847
Other income producing property		115		182		52		349		220,608		220,957
Consumer		793		205		806		1,804		523,236		525,040
Other loans		—		—		—		—		1,457		1,457
	$	7,496	$	3,483	$	8,235	$	19,214	$	8,909,298	$	8,928,512
December 31, 2018
Commercial real estate:
Construction and land development	$	693	$	305	$	452	$	1,450	$	839,995	$	841,445
Commercial non-owner occupied		68		18		396		482		1,415,069		1,415,551
Commercial owner occupied		1,639		1,495		904		4,038		1,513,513		1,517,551
Consumer real estate:
Consumer owner occupied		1,460		789		943		3,192		1,933,073		1,936,265
Home equity loans		744		532		713		1,989		493,159		495,148
Commercial and industrial		898		120		573		1,591		1,053,361		1,054,952
Other income producing property		169		26		289		484		213,869		214,353
Consumer		437		174		718		1,329		447,335		448,664
Other loans		—		—		—		—		9,357		9,357
	$	6,108	$	3,459	$	4,988	$	14,555	$	7,918,731	$	7,933,286
September 30, 2018
Commercial real estate:
Construction and land development	$	535	$	537	$	77	$	1,149	$	901,687	$	902,836
Commercial non-owner occupied		466		—		676		1,142		1,278,186		1,279,328
Commercial owner occupied		2,562		1,249		871		4,682		1,444,387		1,449,069
Consumer real estate:
Consumer owner occupied		866		264		920		2,050		1,842,153		1,844,203
Home equity loans		1,667		296		749		2,712		470,669		473,381
Commercial and industrial		716		297		905		1,918		989,924		991,842
Other income producing property		1,163		—		249		1,412		208,571		209,983
Consumer		702		171		686		1,559		437,230		438,789
Other loans		—		—		—		—		17,047		17,047
	$	8,677	$	2,814	$	5,133	$	16,624	$	7,589,854	$	7,606,478

The following table presents an aging analysis of past due loans (includes nonaccrual loans), segregated by class for acquired non-credit impaired loans:


	30 - 59 Days		60 - 89 Days		90+ Days		Total				Total
(Dollars in thousands)	Past Due		Past Due		Past Due		Past Due		Current		Loans
September 30, 2019
Commercial real estate:
Construction and land development	$	323	$	—	$	162	$	485	$	52,817	$	53,302
Commercial non-owner occupied		697		—		255		952		502,491		503,443
Commercial owner occupied		2,401		168		723		3,292		341,748		345,040
Consumer real estate:
Consumer owner occupied		953		163		327		1,443		541,989		543,432
Home equity loans		653		201		1,137		1,991		196,121		198,112
Commercial and industrial		857		32		321		1,210		124,882		126,092
Other income producing property		1,008		293		85		1,386		101,707		103,093
Consumer		881		134		506		1,521		91,568		93,089
	$	7,773	$	991	$	3,516	$	12,280	$	1,953,323	$	1,965,603
December 31, 2018
Commercial real estate:
Construction and land development	$	647	$	45	$	365	$	1,057	$	164,013	$	165,070
Commercial non-owner occupied		607		21		283		911		678,342		679,253
Commercial owner occupied		964		1,006		—		1,970		419,871		421,841
Consumer real estate:
Consumer owner occupied		1,127		621		789		2,537		626,276		628,813
Home equity loans		1,286		442		2,209		3,937		238,488		242,425
Commercial and industrial		2,648		130		19		2,797		209,740		212,537
Other income producing property		603		276		129		1,008		132,102		133,110
Consumer		574		209		532		1,315		110,462		111,777
	$	8,456	$	2,750	$	4,326	$	15,532	$	2,579,294	$	2,594,826
September 30, 2018
Commercial real estate:
Construction and land development	$	6	$	199	$	373	$	578	$	221,984	$	222,562
Commercial non-owner occupied		3,931		48		—		3,979		680,814		684,793
Commercial owner occupied		564		198		711		1,473		454,330		455,803
Consumer real estate:
Consumer owner occupied		552		405		575		1,532		645,532		647,064
Home equity loans		1,295		527		2,421		4,243		255,315		259,558
Commercial and industrial		116		589		264		969		246,953		247,922
Other income producing property		804		343		129		1,276		149,095		150,371
Consumer		541		298		465		1,304		116,725		118,029
	$	7,809	$	2,607	$	4,938	$	15,354	$	2,770,748	$	2,786,102

The following table presents an aging analysis of past due loans (includes nonaccrual loans), segregated by class for acquired credit impaired loans:


	30 - 59 Days		60 - 89 Days		90+ Days		Total				Total
(Dollars in thousands)	Past Due		Past Due		Past Due		Past Due		Current		Loans
September 30, 2019
Commercial real estate	$	444	$	252	$	2,671	$	3,367	$	145,767	$	149,134
Commercial real estate—construction and development		88		—		261		349		26,581		26,930
Residential real estate		2,317		1,143		5,016		8,476		166,568		175,044
Consumer		948		185		499		1,632		35,180		36,812
Commercial and industrial		282		—		77		359		7,753		8,112
	$	4,079	$	1,580	$	8,524	$	14,183	$	381,849	$	396,032
December 31, 2018
Commercial real estate	$	876	$	112	$	4,533	$	5,521	$	191,243	$	196,764
Commercial real estate—construction and development		115		12		2,816		2,943		29,999		32,942
Residential real estate		4,620		1,251		8,487		14,358		193,124		207,482
Consumer		722		90		839		1,651		40,841		42,492
Commercial and industrial		2,437		—		88		2,525		7,518		10,043
	$	8,770	$	1,465	$	16,763	$	26,998	$	462,725	$	489,723
September 30, 2018
Commercial real estate	$	1,517	$	375	$	5,608	$	7,500	$	202,018	$	209,518
Commercial real estate—construction and development		768		309		2,905		3,982		30,330		34,312
Residential real estate		6,506		1,392		8,371		16,269		201,750		218,019
Consumer		671		168		891		1,730		42,351		44,081
Commercial and industrial		2,625		83		88		2,796		7,875		10,671
	$	12,087	$	2,327	$	17,863	$	32,277	$	484,324	$	516,601

The following is a summary of certain information pertaining to impaired non-acquired loans:


	Unpaid		Recorded		Gross
	Contractual		Investment		Recorded		Total
	Principal		With No		Investment		Recorded		Related
(Dollars in thousands)	Balance		Allowance		With Allowance		Investment		Allowance
September 30, 2019
Commercial real estate:
Construction and land development	$	33,063	$	225	$	32,448	$	32,673	$	587
Commercial non-owner occupied		146		74		13		87		—
Commercial owner occupied		8,401		5,544		1,591		7,135		33
Consumer real estate:
Consumer owner occupied		5,441		3,610		1,517		5,127		33
Home equity loans		2,476		1,087		1,258		2,345		121
Commercial and industrial		5,779		1,874		3,439		5,313		387
Other income producing property		2,489		430		1,666		2,096		58
Consumer		145		—		91		91		2
Total	$	57,940	$	12,844	$	42,023	$	54,867	$	1,221
December 31, 2018
Commercial real estate:
Construction and land development	$	38,314	$	339	$	37,574	$	37,913	$	788
Commercial non-owner occupied		1,157		536		489		1,025		70
Commercial owner occupied		5,085		3,101		1,041		4,142		27
Consumer real estate:
Consumer owner occupied		7,291		4,992		1,769		6,761		41
Home equity loans		2,953		1,129		1,697		2,826		142
Commercial and industrial		1,332		467		824		1,291		416
Other income producing property		3,117		150		2,722		2,872		142
Consumer		211		—		188		188		2
Total	$	59,460	$	10,714	$	46,304	$	57,018	$	1,628
September 30, 2018
Commercial real estate:
Construction and land development	$	36,203	$	1,029	$	34,747	$	35,776	$	723
Commercial non-owner occupied		1,480		812		503		1,315		81
Commercial owner occupied		5,507		2,668		1,883		4,551		40
Consumer real estate:
Consumer owner occupied		5,914		4,478		942		5,420		28
Home equity loans		3,141		1,135		1,891		3,026		171
Commercial and industrial		1,462		467		942		1,409		475
Other income producing property		3,165		158		2,772		2,930		133
Consumer		284		—		213		213		6
Total	$	57,156	$	10,747	$	43,893	$	54,640	$	1,657

Acquired credit impaired loans are accounted for in pools as shown on page 22 rather than being individually evaluated for impairment; therefore, the table above excludes acquired credit impaired loans.

The following summarizes the average investment in impaired non-acquired loans, and interest income recognized on these loans:


	Three Months Ended September 30,
	2019				2018
	Average				Average
	Investment in		Interest Income		Investment in		Interest Income
(Dollars in thousands)	Impaired Loans		Recognized		Impaired Loans		Recognized
Commercial real estate:
Construction and land development	$	34,401	$	177	$	39,084	$	158
Commercial non-owner occupied		94		1		1,332		5
Commercial owner occupied		6,288		129		4,650		81
Consumer real estate:
Consumer owner occupied		5,346		36		5,524		32
Home equity loans		2,391		36		3,085		30
Commercial and industrial		3,993		123		1,622		8
Other income producing property		2,080		14		3,085		32
Consumer		95		—		235		—
Total Impaired Loans	$	54,688	$	516	$	58,617	$	346


	Nine Months Ended September 30,
	2019				2018
	Average				Average
	Investment in		Interest Income		Investment in		Interest Income
(Dollars in thousands)	Impaired Loans		Recognized		Impaired Loans		Recognized
Commercial real estate:
Construction and land development	$	35,293	$	967	$	39,503	$	968
Commercial non-owner occupied		556		6		1,345		19
Commercial owner occupied		5,638		290		5,096		228
Consumer real estate:
Consumer owner occupied		5,944		129		5,527		120
Home equity loans		2,586		100		3,019		95
Commercial and industrial		3,302		209		1,282		43
Other income producing property		2,484		68		3,034		120
Consumer		140		—		226		—
Other loans		—		—		—		—
Total Impaired Loans	$	55,943	$	1,769	$	59,032	$	1,593

The following is a summary of information pertaining to non-acquired nonaccrual loans by class, including restructured loans:


	September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018
Commercial non-owner occupied real estate:
Construction and land development	$	412	$	424	$	404
Commercial non-owner occupied		457		831		1,110
Total commercial non-owner occupied real estate		869		1,255		1,514
Consumer real estate:
Consumer owner occupied		7,374		7,109		6,406
Home equity loans		1,273		2,333		2,623
Total consumer real estate		8,647		9,442		9,029
Commercial owner occupied real estate		4,062		1,068		1,063
Commercial and industrial		2,565		647		957
Other income producing property		628		500		474
Consumer		1,539		1,267		1,177
Restructured loans		544		648		1,065
Total loans on nonaccrual status	$	18,854	$	14,827	$	15,279

The following is a summary of information pertaining to acquired non-credit impaired nonaccrual loans by class, including restructured loans:


	September 30,		December 31,		September 30,
(Dollars in thousands)	2019		2018		2018
Commercial non-owner occupied real estate:
Construction and land development	$	1,031	$	252	$	402
Commercial non-owner occupied		266		283		—
Total commercial non-owner occupied real estate		1,297		535		402
Consumer real estate:
Consumer owner occupied		1,739		3,864		2,408
Home equity loans		3,034		4,512		4,901
Total consumer real estate		4,773		8,376		7,309
Commercial owner occupied real estate		933		1,470		904
Commercial and industrial		692		1,296		354
Other income producing property		270		244		249
Consumer		1,631		1,568		1,580
Total loans on nonaccrual status	$	9,596	$	13,489	$	10,798

In the course of resolving delinquent loans, the Bank may choose to restructure the contractual terms of certain loans. Any loans that are modified are reviewed by the Bank to determine if a troubled debt restructuring (“TDR” or “restructured loan”) has occurred. The Bank designates loan modifications as TDRs when it grants a concession to a borrower that it would not otherwise consider due to the borrower experiencing financial difficulty (FASB ASC Topic 310-40). The concessions granted on TDRs generally include terms to reduce the interest rate, extend the term of the debt obligation, or modify the payment structure on the debt obligation.

Loans on nonaccrual status at the date of modification are initially classified as nonaccrual TDRs. Loans on accruing status at the date of concession are initially classified as accruing TDRs if the note is reasonably assured of repayment and performance is expected in accordance with its modified terms. Such loans may be designated as nonaccrual loans subsequent to the concession date if reasonable doubt exists as to the collection of interest or principal under the restructuring agreement. Nonaccrual TDRs are returned to accruing status when there is economic substance to the restructuring, there is documented credit evaluation of the borrower’s financial condition, the remaining balance is reasonably assured of repayment in accordance with its modified terms, and the borrower has demonstrated sustained repayment performance in accordance with the modified terms for a reasonable period of time (generally a minimum of six months). For the nine months ended September 30, 2019 and 2018, our TDRs were not material.