SouthState (SSB) 10-K 26 Feb 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 22, 2021	Jun. 30, 2020
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2020
Entity File Number	001-12669
Entity Registrant Name	SOUTH STATE CORP
Entity Incorporation, State or Country Code	SC
Entity Tax Identification Number	57-0799315
Entity Address, Address Line One	1101 First Street South, Suite 202,
Entity Address, City or Town	Winter Haven
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33880
City Area Code	863
Local Phone Number	293-4710
Title of 12(b) Security	Common Stock
Trading Symbol	SSB
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 3,336,684,000
Entity Common Stock, Shares Outstanding		71,032,588
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0000764038
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Cash and cash equivalents:
Cash and due from banks	$ 363,306	$ 262,019
Federal funds sold and interest-bearing deposits with banks	3,582,410	377,692
Deposits in other financial institutions (restricted cash)	663,539	48,993
Total cash and cash equivalents	4,609,255	688,704
Trading securities, at fair value	10,674
Investment securities:
Securities held-to-maturity (fair value of $957,183 and $0)	955,542
Securities available-for-sale, at fair value	3,330,672	1,956,047
Other investments	160,443	49,124
Total investment securities	4,446,657	2,005,171
Loans held for sale	290,467	59,363
Loans:
Total loans - ASU 2016-13	24,664,134
Less allowance for credit losses	(457,309)	(56,927)
Loans, net	24,206,825	11,313,113
Other real estate owned	11,914	6,539
Bank property held for sale	36,006	5,425
Premises and equipment, net	579,239	317,321
Bank owned life insurance	559,368	234,567
Deferred tax assets	110,946	31,316
Derivatives assets	813,899	16,252
Mortgage servicing rights	43,820	30,525
Core deposit and other intangibles	162,592	49,816
Goodwill	1,563,942	1,002,900
Other assets	344,269	160,869
Total assets	37,789,873	15,921,881
Deposits:
Noninterest-bearing	9,711,338	3,245,306
Interest-bearing	20,982,544	8,931,790
Total deposits	30,693,882	12,177,096
Federal funds purchased	384,735	56,581
Securities sold under agreements to repurchase	394,931	242,160
Corporate and subordinated debentures	390,179	115,833
Other borrowings	390,179	700,103
Reserve for unfunded commitments	43,380	335
Derivative liabilities	804,832	31,273
Other liabilities	430,054	225,487
Total liabilities	33,141,993	13,548,868
Shareholders' equity:
Common stock - $2.50 par value; authorized 160,000,000 and 80,000,000 shares; 70,973,477 and 33,744,385 shares issued and outstanding, respectively	177,434	84,361
Surplus	3,765,406	1,607,740
Retained earnings	657,451	679,895
Accumulated other comprehensive income	47,589	1,017
Total shareholders' equity	4,647,880	2,373,013
Total liabilities and shareholders' equity	37,789,873	15,921,881
Acquired - non-purchased credit deteriorated loans
Loans:
Total loans - ASU 2016-13	9,458,869	1,760,427
Acquired - purchased credit deteriorated loans (formerly acquired credit-impaired loans)
Loans:
Total loans - ASU 2016-13	2,915,809	356,782
Non-acquired loans
Loans:
Total loans - ASU 2016-13	$ 12,289,456	9,252,831
Less allowance for credit losses		(56,927)
Loans, net		$ 9,195,904

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Investment securities:
Securities held to maturity, fair value (in dollars)	$ 957,183	$ 0
Shareholders' equity:
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50
Common stock, shares authorized	160,000,000	80,000,000
Common stock, shares issued	70,973,477	33,744,385
Common stock, shares outstanding	70,973,477	33,744,385

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest income:
Loans, including fees	$ 851,199	$ 534,790	$ 521,478
Investment securities:
Taxable	47,420	39,949	35,563
Tax-exempt	7,212	6,186	6,152
Federal funds sold, securities purchased under agreements to resell and interest-bearing deposits with banks	4,198	9,902	4,015
Total interest income	910,029	590,827	567,208
Interest expense:
Deposits	55,442	65,920	45,452
Federal funds purchased and securities sold under agreements to repurchase	1,950	2,627	2,356
Corporate and subordinated debentures	12,968	5,641	5,293
Other borrowings	13,204	12,364	891
Total interest expense	83,564	86,552	53,992
Net interest income	826,465	504,275	513,216
Provision for credit losses	235,989	12,777	13,783
Net interest income after provision for credit losses	590,476	491,498	499,433
Noninterest income:
Securities gains (losses), net	50	2,711	(655)
Recoveries on acquired loans		6,847	9,117
Other	26,389	8,872	10,552
Total noninterest income	311,140	143,565	145,749
Noninterest expense:
Salaries and employee benefits	416,599	234,747	233,130
Occupancy expense	75,587	47,457	49,165
Information services expense	59,843	35,477	34,322
OREO expense and loan related	3,568	3,242	3,510
Pension plan termination expense		9,526
Amortization of intangibles	26,992	13,084	14,209
Supplies, printing and postage expense	8,679	5,881	5,839
Professional fees	14,033	10,325	8,883
FDIC assessment and other regulatory charges	10,713	4,545	8,405
Advertising and marketing	4,092	4,309	4,221
Merger and branch consolidation related expense	85,906	4,552	29,868
Swap termination expense	38,787
Other	52,845	31,493	29,375
Total noninterest expense	797,644	404,638	420,927
Earnings:
Income before provision for income taxes	103,972	230,425	224,255
Provision (benefit) for income taxes	(16,660)	43,942	45,384
Net income	$ 120,632	$ 186,483	$ 178,871
Earnings per common share:
Basic (in dollars per share)	$ 2.20	$ 5.40	$ 4.90
Diluted (in dollars per share)	$ 2.19	$ 5.36	$ 4.86
Weighted average common shares outstanding:
Basic (in shares)	54,756	34,561	36,530
Diluted (in shares)	55,063	34,797	36,776
Fees on deposit accounts
Noninterest income:
Noninterest income	$ 84,319	$ 75,435	$ 81,649
Mortgage banking income
Noninterest income:
Noninterest income	106,202	17,564	13,590
Trust and investment services income
Noninterest income:
Noninterest income	29,437	29,244	30,229
Correspondent banking and capital market income
Noninterest income:
Noninterest income	$ 64,743	$ 2,892	$ 1,267

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consolidated Statements of Comprehensive Income
Net income	$ 120,632	$ 186,483	$ 178,871
Unrealized gains (losses) on available-for-sale securities:
Unrealized holding gains (losses) arising during period	47,401	36,211	(17,322)
Tax effect	(11,544)	(7,966)	3,843
Reclassification adjustment for (gains) losses included in net income	(50)	2,655	655
Tax effect	11	(584)	(145)
Net of tax amount	35,818	30,316	(12,969)
Unrealized gains (losses) on derivative financial instruments qualifying as cash flow hedges:
Unrealized holding (losses) gains arising during period	(33,512)	(13,394)	42
Tax effect	7,372	2,947	(9)
Reclassification adjustment for losses (gains)	47,303	(349)	155
Tax effect	(10,407)	77	(34)
Net of tax amount	10,756	(10,719)	154
Change in pension plan and retiree medical plan obligation:
Change in pension and retiree medical plan obligation during period	(160)	25	490
Tax effect	41	(5)	(108)
Reclassification adjustment for changes included in net income	152	8,053	1,187
Tax effect	(35)	(1,772)	(261)
Net of tax amount	(2)	6,301	1,308
Other comprehensive income (loss), net of tax	46,572	25,898	(11,507)
Comprehensive income	$ 167,204	$ 212,381	$ 167,364

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Common Stock	Surplus	Retained EarningsCumulative Effect of Adoption of ASU	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Cumulative Effect of Adoption of ASU	Total
Balance at Dec. 31, 2017	$ 91,899	$ 1,807,601		$ 419,847	$ (10,427)		$ 2,308,920
Balance (in shares) at Dec. 31, 2017	36,759,656
Increase (Decrease) in Stockholders' Equity
Net income				178,871			178,871
Other comprehensive income (loss), net of tax effects					(11,507)		(11,507)
Total comprehensive income (loss)							167,364
Cash dividends declared on common stock per share				(50,557)			(50,557)
AOCI reclassification to retained earnings from adoption of ASU 2018-02				2,947	(2,947)
Employee stock purchases	$ 45	1,286					1,331
Employee stock purchases (in shares)	18,110
Stock options exercised	$ 84	948					1,032
Stock options exercised (in shares)	33,424
Restricted stock awards (forfeitures)	$ 10	(10)
Restricted stock awards (forfeitures) (in shares)	4,069
Stock issued pursuant to restricted stock units	$ 99	(99)
Stock issued pursuant to restricted stock units (in shares)	39,541
Common stock repurchased - buyback plan	$ (2,500)	(65,904)					(68,404)
Common stock repurchased - buyback plan (in shares)	(1,000,000)
Common stock repurchased	$ (63)	(2,110)					(2,173)
Common stock repurchased (in shares)	(25,251)
Share-based compensation expense		8,783					8,783
Balance at Dec. 31, 2018	$ 89,574	1,750,495		551,108	(24,881)		2,366,296
Balance (in shares) at Dec. 31, 2018	35,829,549
Increase (Decrease) in Stockholders' Equity
Net income				186,483			186,483
Other comprehensive income (loss), net of tax effects					25,898		25,898
Total comprehensive income (loss)							212,381
Cash dividends declared on common stock per share				(57,696)			(57,696)
Employee stock purchases	$ 53	1,341					1,394
Employee stock purchases (in shares)	21,100
Stock options exercised	$ 92	1,138					1,230
Stock options exercised (in shares)	36,978
Restricted stock awards (forfeitures)	$ 15	(15)
Restricted stock awards (forfeitures) (in shares)	5,889
Stock issued pursuant to restricted stock units	$ 129	(129)
Stock issued pursuant to restricted stock units (in shares)	51,543
Common stock repurchased - buyback plan	$ (5,413)	(151,532)					(156,945)
Common stock repurchased - buyback plan (in shares)	(2,165,000)
Common stock repurchased	$ (89)	(2,397)					(2,486)
Common stock repurchased (in shares)	(35,674)
Share-based compensation expense		8,839					8,839
Balance at Dec. 31, 2019	$ 84,361	1,607,740		679,895	1,017		$ 2,373,013
Balance (in shares) at Dec. 31, 2019	33,744,385						33,744,385
Increase (Decrease) in Stockholders' Equity
Net income				120,632			$ 120,632
Other comprehensive income (loss), net of tax effects					46,572		46,572
Total comprehensive income (loss)							167,204
Cash dividends declared on common stock per share				(98,256)			(98,256)
Employee stock purchases	$ 81	1,456					1,537
Employee stock purchases (in shares)	32,476
Stock options exercised	$ 131	1,550					1,681
Stock options exercised (in shares)	52,331
Restricted stock awards (forfeitures)	$ 22	(22)
Restricted stock awards (forfeitures) (in shares)	8,828
Stock issued pursuant to restricted stock units	$ 768	(768)
Stock issued pursuant to restricted stock units (in shares)	307,096
Common stock repurchased - buyback plan	$ (800)	(23,915)					(24,715)
Common stock repurchased - buyback plan (in shares)	(320,000)
Common stock issued for acquisition	$ 93,178	2,153,149					2,246,327
Common stock issued for acquisition (in shares)	37,271,069
Common stock repurchased	$ (307)	(7,409)					(7,716)
Common stock repurchased (in shares)	(122,708)
Share-based compensation expense		23,318					23,318
Stock options and restricted stock acquired and converted pursuant to CenterState acquisition		10,307					10,307
Balance (ASU 2016-13) at Dec. 31, 2020			$ (44,820)			$ (44,820)
Balance at Dec. 31, 2020	$ 177,434	$ 3,765,406		$ 657,451	$ 47,589		$ 4,647,880
Balance (in shares) at Dec. 31, 2020	70,973,477						70,973,477

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consolidated Statements of Changes in Shareholders' Equity
Cash dividends declared, per share (in dollars per share)	$ 1.88	$ 1.67	$ 1.38

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net income	$ 120,632	$ 186,483	$ 178,871
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	46,367	33,121	35,696
Provision for credit losses	235,989	12,777	13,783
Deferred income taxes	(44,282)	(1,492)	15,176
Other-than-temporary impairment on securities	0		(991)
(Gains) losses on sale of securities, net	(50)	(2,711)	655
Trading securities revenue	(486)
Purchases of trading securities	(201,095)
Proceeds from sale of trading securities	190,907
Share-based compensation expense	23,318	8,839	8,783
Accretion of discount related to acquired loans	(56,170)	(12,986)	(27,756)
Losses on disposal of premises and equipment	5,010	3,617	1,568
(Gains) losses on sale of bank premises and other repossessed real estate	(546)	178	(1,969)
Net amortization of premiums on investment securities	22,231	7,260	7,567
Bank premises and other repossessed real estate write downs	1,085	1,193	1,420
Fair value adjustment for loans held for sale	4,705	(1,057)	(521)
Originations and purchases of loans held for sale	(2,959,310)	(847,684)	(622,589)
Proceeds from sales of loans held for sale	3,297,155	824,712	679,811
Gains on sales of loans held for sale	(120,077)	(12,408)	(8,739)
Bank owned life insurance income	(10,170)	(5,567)	(5,556)
Net change in:
Accrued interest receivable	(19,362)	(777)	(3,269)
Prepaid assets	(8,945)	(2,411)	1,951
Operating leases	6,434	1,457
Bank owned life insurance	(1,231)	1,105	583
Derivative assets	98,807	(10,373)	(5,157)
Miscellaneous other assets	27,365	(29,932)	8,962
Accrued interest payable	(3,683)	197	1,930
Accrued income taxes	(77,946)	(8,536)	143
Derivative liabilities	(113,788)	26,064	4,545
Miscellaneous other liabilities	74,079	9,959	(1,186)
Net cash provided by operating activities	536,943	181,028	283,711
Cash flows from investing activities:
Proceeds from sales of investment securities available-for-sale	100,754	242,733	73,054
Proceeds from maturities and calls of investment securities held-to-maturity	2,534		2,530
Proceeds from maturities and calls of investment securities available-for-sale	957,250	308,109	224,713
Proceeds from sales of other investment securities	71,788	45	15,938
Purchases of investment securities available-for-sale	(1,309,450)	(955,505)	(191,313)
Purchases of investment securities held-to-maturity	(958,391)
Purchases of other investment securities	(85,511)	(23,566)	(18,494)
Net increase in loans	(156,360)	(363,446)	(391,428)
Net cash received from acquisitions	2,566,376
Recoveries of loans previously charged off	11,776	3,914	3,300
Purchases of premises and equipment	(16,930)	(15,798)	(14,538)
Proceeds from redemption and payout of bank owned life insurance policies	19,655
Proceeds from sale of bank premises and other repossessed real estate	19,156	8,450	13,943
Proceeds from sale of premises and equipment	7,131	11	146
Net cash provided by (used in) investing activities	1,229,778	(795,053)	(282,149)
Cash flows from financing activities:
Net increase in deposits	2,902,023	530,163	114,779
Net increase (decrease) in federal funds purchased and securities sold under agreements to repurchase and other short-term borrowings	79,379	28,092	(16,208)
Proceeds from borrowings	500,000	700,001	590,001
Repayment of borrowings	(1,200,103)	(150,007)	(540,007)
Common stock issuance	1,537	1,394	1,331
Common stock repurchases	(32,431)	(159,431)	(70,577)
Dividends paid on common stock	(98,256)	(57,696)	(50,557)
Stock options exercised	1,681	1,230	1,032
Net cash provided by financing activities	2,153,830	893,746	29,794
Net increase in cash and cash equivalents	3,920,551	279,721	31,356
Cash and cash equivalents at beginning of period	688,704	408,983	377,627
Cash and cash equivalents at end of period	4,609,255	688,704	408,983
Cash paid for:
Interest	87,246	86,355	52,062
Income taxes	103,801	55,674	31,941
Initial measurement and recognition of operating lease assets in exchange for lease liabilities per ASU 2016-02		82,160
Recognition of operating lease assets in exchange for lease liabilities	9,426	10,239
Acquisitions:
Fair value of tangible assets acquired	18,825,354		(7,247)
Other intangible assets acquired	140,862		3,321
Liabilities assumed	17,270,550		(612)
Net identifiable assets acquired over liabilities assumed	561,042		(3,314)
Common stock issued in acquisition	2,246,327
Real estate acquired in full or in partial settlement of loans	$ 4,660	$ 8,666	$ 13,391

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	Note 1—Summary of Significant Accounting Policies Nature of Operations South State Corporation (the “Company”) is a financial holding company whose principal activity is the ownership and management of its wholly owned subsidiary, South State Bank, National Association (the “Bank”). The Bank operates South State Advisory, Inc. (formerly First Southeast 401k Fiduciaries, Inc.), a wholly-owned registered investment advisor. We merged Minis & Co., Inc., another registered investment advisor that was wholly-owned by the Bank, with and into South State Advisory, Inc. effective January 1, 2019. We will continue to use the name Minis & Company as a Doing Business As (DBA) going forward. Through the merger with CenterState Bank Corporation (“CSFL”) in the second quarter of 2020, the Bank also owns CBI Holding Company, LLC (“CBI”), which in turn owns Corporate Billing, LLC (“Corporate Billing”), a transaction-based finance company headquartered in Decatur, Alabama that provides factoring, invoicing, collection and accounts receivable management services to transportation companies and automotive parts and service providers nationwide. Also, through the merger with CSFL in the second quarter of 2020, the holding company operates R4ALL, Inc., which manages a troubled loan purchased from the Bank to its eventual disposition and SSB Insurance Corp., a captive insurance subsidiary pursuant to Section 831(b) of the U.S. Tax Code. The Company also operates a correspondent banking division within the national bank subsidiary, of which the majority of its bond salesmen, traders and operational personnel are housed in facilities located in Birmingham, Alabama and Atlanta, Georgia. The Bank provides general banking services within 28 counties in South Carolina, 32 counties in Florida, 9 counties in North Carolina, 25 counties in Georgia, 5 counties in Alabama, and 4 counties in Virginia. The accounting and reporting policies of the Company and its consolidated subsidiary conform to accounting principles generally accepted in the United States of America (‘U.S. GAAP”). There are 20 unconsolidated subsidiaries of the Company that were established for the purpose of issuing in the aggregate of approximately $153.5 million of trust preferred securities. See Note 12—Other Borrowings for further detailed descriptions of our trust preferred securities. Unless otherwise mentioned or unless the context requires otherwise, references herein to "South State," the "Company" "we," "us," "our" or similar references mean South State Corporation and its consolidated subsidiaries. References to the “Bank” means South State Bank, National Association. Basis of Consolidation The consolidated financial statements include the accounts of the Company and other entities in which it has a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation. Assets held by the Company in trust are not assets of the Company and are not included in the accompanying consolidated financial statements. Segments The Company, through its Bank subsidiary, provides a broad range of financial services to individuals and companies in South Carolina, North Carolina, Florida, Alabama, Georgia and Virginia. These services include demand, time and savings deposits; lending and credit card servicing; ATM processing; mortgage banking services; correspondent banking services and wealth management and trust services. While the Company’s decision makers monitor the revenue streams of the various financial products and services, operations are managed and financial performance is evaluated on an organization- wide basis. Accordingly, the Company’s banking and finance operations are not considered by management to constitute more than one reportable operating segment. Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the consolidated balance sheet and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term relate to the determination of the allowance for credit losses for loans and investment securities held-to-maturity, fair value of financial instruments, fair values of assets and liabilities acquired in business combinations, loss estimates related to loans and other real estate acquired, evaluating impairment of investment securities, goodwill impairment tests and valuation of deferred tax assets. In connection with the determination of the allowance for credit losses, management has identified specific loans as well as adopted a policy of providing amounts for loan valuation purposes which are not identified with any specific loan but are derived from models based on macroeconomic factors and forecasts. Management believes that the allowance for credit losses is adequate. While management uses available information to recognize losses on loans, future additions to the allowance may be necessary based on changes in economic forecasts. In addition, regulatory agencies, as an integral part of the examination process, periodically review the banking subsidiary’s allowance for credit losses. Such agencies may require additions to the allowance based on their judgments about information available to them at the time of their examination. Concentrations of Credit Risk The Company’s Bank subsidiary grants agribusiness, commercial, and residential loans to customers throughout South Carolina, North Carolina, Florida, Alabama, Virginia and Georgia. Although the subsidiary has a diversified loan portfolio, a substantial portion of their borrowers’ abilities to honor their contracts is dependent upon economic conditions within South Carolina, North Carolina, Florida, Alabama, Virginia, Georgia and the surrounding regions. The Company considers concentrations of credit to exist when, pursuant to regulatory guidelines, the amounts loaned to a multiple number of borrowers engaged in similar business activities which would cause them to be similarly impacted by general economic conditions represents 25% of total Tier 1 capital plus regulatory adjusted allowance for credit losses of the Company, or $841.1 million at December 31, 2020. Based on this criteria, the Company had five such credit concentrations at December 31, 2020, including loans on hotels and motels of $969.9 million, loans to lessors of nonresidential buildings (except mini-warehouses) of $3.7 billion, loans secured by owner occupied nonresidential buildings of $3.1 billion, loans to lessors of residential buildings (investment properties and multi-family) of $1.1 billion and loans secured by 1 st Cash and Cash Equivalents For the purpose of presentation in the consolidated statements of cash flows, cash and cash equivalents include cash on hand, cash items in process of collection, amounts due from banks including restricted pledged cash, interest bearing deposits with banks, purchases of securities under agreements to resell, and federal funds sold. Due from bank balances are maintained at other financial institutions. Federal funds sold are generally purchased and sold for one-day periods, but may, from time to time, have longer terms. The Company enters from time to time into purchases of securities under agreements to resell substantially identical securities. When the Company enters into such repurchase agreements, the securities purchased under agreements to resell generally consist of U.S. government-sponsored entities and agency mortgage-backed securities. The Company may elect to use other asset classes at its discretion. It is the Company’s practice to take possession of securities purchased under agreements to resell. The securities are delivered into the Company’s account maintained by a third- party custodian designated by the Company under a written custodial agreement that explicitly recognizes the Company’s interest in the securities. The Company monitors the market value of the underlying securities, including accrued interest, which collateralizes the related receivable on agreements to resell. Historically, these agreements were considered to be cash equivalents with maturities of three months or less. The Company held no securities under agreements to resell at December 31, 2020. Trading Securities The Company has a trading securities portfolio where t For this portfolio, interest income is included in the net interest margin and realized and unrealized gains and losses are included in correspondent banking and capital market income, a component of Non-interest Income in our “Consolidated Statements of Income.” Securities purchased for this portfolio have primarily been municipal securities and are held for short periods of time. Investment Securities Debt securities that management has the positive intent and ability to hold to maturity are classified as “held-to-maturity” and carried at amortized cost. Securities not classified as held-to-maturity, including equity securities with readily determinable fair values, are classified as “available-for-sale” and carried at fair value with unrealized gains and losses excluded from earnings and reported in other comprehensive income. Purchase premiums and discounts are recognized in interest income using methods approximating the interest method over the terms of the securities. Gains and losses realized on sales of securities available-for-sale are determined using the specific identification method. Management no longer evaluates securities for other-than-temporary impairment, otherwise referred to herein as OTTI, as ASC Subtopic 326-30, Financial Instruments—Credit Losses—Available-for-Sale Debt Securities, changes the accounting for recognizing impairment on available-for-sale debt securities. Each quarter Management evaluates impairment where there has been a decline in fair value below the amortized cost basis of a security to determine whether there is a credit loss associated with the decline in fair value. Management considers the nature of the collateral, potential future changes in collateral values, default rates, delinquency rates, third-party guarantees, credit ratings, interest rate changes since purchase, volatility of the security’s fair value and historical loss information for financial assets secured with similar collateral among other factors. Credit losses are calculated individually, rather than collectively, using a discounted cash flow method, whereby Management compares the present value of expected cash flows with the amortized cost basis of the security. The credit loss component would be recognized through the provision for credit losses in the Statements of Income. (see Note 4—Investment Securities). Other investments include stock acquired for regulatory purposes, investments in unconsolidated subsidiaries and other nonmarketable investment securities. Stock acquired for regulatory purposes include Federal Home Loan Bank of Atlanta (“FHLB”) stock and Federal Reserve Bank (“FRB”) stock. These securities do not have a readily determinable fair value because their ownership is restricted and they lack a market for trading. As a result, these securities are carried at cost and are periodically evaluated for impairment. Investments in unconsolidated subsidiaries represent a minority investment in SCBT Capital Trust I, SCBT Capital Trust II, SCBT Capital Trust III, TSB Statutory Trust I, SAVB Capital Trust I, SAVB Capital Trust II, Southeastern Bank Financial Statutory Trust I, Southeastern Bank Financial Statutory Trust II, Provident Community Bancshares Capital Trust I, FCRV Statutory Trust I, Community Capital Statutory Trust I, CSBC Statutory Trust I, Provident Community Bancshares Capital Trust II, CenterState Banks of Florida Statutory Trust I, Valrico Capital Statutory Trust, Federal Trust Statutory Trust I, Gulfstream Bancshares Capital Trust II, Homestead Statutory Trust I, BSA Financial Statutory Trust I and MRCB Statutory Trust II. These investments are recorded at cost and the Company receives quarterly dividend payments on these investments. Other nonmarketable investment securities consist of Business Development Corporation stock and stock in Banker’s Banks. These investments also do not have a readily determinable fair value because their ownership is restricted and they lack a market for trading. As a result, these securities are carried at cost and are periodically evaluated for impairment. Loans Held for Sale Loans originated and intended for sale are carried at the estimated fair value in the aggregate. Estimated fair value is determined on the basis of existing forward commitments, or the current market value of similar loans. Net unrealized losses, if any, are recognized through a valuation allowance by charges to income. Loans held-for-sale are sold to investors either under guaranteed delivery or with the best effort intent and ability to sell loans as long as they meet the underwriting standards of the potential investor. Loans Loans that management has originated and has the intent and ability to hold for the foreseeable future or until maturity or pay off generally are reported at their unpaid principal balances, less unearned income and net of any deferred loan fees and costs. Unearned income on installment loans is recognized as income over the terms of the loans by methods that generally approximate the interest method. Interest on other loans is calculated by using the simple interest method on daily balances of the principal amount outstanding. We place non acquired loans and acquired loans on nonaccrual once reasonable doubt exists about the collectability of all principal and interest due. Generally, this occurs when principal or interest is 90 days or more past due, unless the loan is well secured and in the process of collection. A loan is evaluated individually for loss when it is on nonaccrual and has a net book balance over $1 million. Large pools of homogeneous loans are collectively evaluated for loss and given a general reserve. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as nonaccrual, provided that management expects to collect all amounts due, including interest accrued at the contractual interest rate for the period of delay. Troubled Debt Restructurings (“TDRs”) The Bank measures expected credit losses over the contractual term of a loan. When determining the contractual term, the Company considers expected prepayments but is precluded from considering expected extensions, renewals, or modifications, unless the Company reasonably expects it will execute a troubled debt restructuring (“TDR”) with a borrower. In the event of a reasonably-expected TDR, the Company factors the reasonably-expected TDR into the current expected credit losses estimate. For consumer loans, the point at which a TDR is reasonably expected is when the Company approves the borrower’s application for a modification (i.e., the borrower qualifies for the TDR) or when the Credit Administration department approves loan concessions on substandard loans. For commercial loans, the point at which a TDR is reasonably expected is when the Company approves the loan for modification or when the Credit Administration department approves loan concessions on substandard loans. The Company uses a discounted cash flow methodology for a TDR to calculate the effect of the concession provided to the borrower within the ACL. A restructuring that results in only a delay in payments that is insignificant is not considered an economic concession. In accordance with the Coronavirus Aid, Relief, and Economic Security Act, also known as the CARES Act, the Company implemented loan modification programs in response to the COVID-19 pandemic in order to provide borrowers with flexibility with respect to repayment terms. The Company’s payment relief assistance includes forbearance, deferrals, extension and re-aging programs, along with certain other modification strategies. The Company elected the accounting policy in the CARES Act to not apply TDR accounting to loans modified for borrowers impacted by the COVID-19 pandemic if the concession meets the criteria as defined under the CARES Act. Allowance for Credit Losses (“ACL”) On January 1, 2020, we adopted the requirements of Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, sometimes referred to herein as ASU 2016-13. Topic 326 was subsequently amended by ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments-Credit Losses; ASU No. 2019-05, Codification Improvements to Topic 326, Financial Instruments-Credit Losses; and ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments. This standard applies to all financial assets measured at amortized cost and off balance sheet credit exposures, including loans, investment securities and unfunded commitments. We applied the standard’s provisions using the modified retrospective method as a cumulative-effect adjustment to retained earnings as of January 1, 2020. With this transition method, we did not have to restate comparative prior periods presented in the financial statements related to Topic 326, but will present comparative prior periods disclosures using the previous accounting guidance for the allowance for loan losses. This adoption method is considered a change in accounting principle requiring additional disclosure of the nature of and reason for the change, which is solely a result of the adoption of the required standard. ACL – Investment Securities Management uses a systematic methodology to determine its ACL for investment securities held-to-maturity. The ACL is a valuation account that is deducted from the amortized cost basis to present the net amount expected to be collected on the held-to-maturity portfolio. Management considers the effects of past events, current conditions, and reasonable and supportable forecasts on the collectability of the portfolio. The Company’s estimate of its ACL involves a high degree of judgment; therefore, Management’s process for determining expected credit losses may result in a range of expected credit losses. Management monitors the held-to-maturity portfolio to determine whether a valuation account would need to be recorded. As of December 31, 2020, the Company had $955.5 million of held-to-maturity securities and no related valuation account. Management no longer evaluates available-for-sale securities for other-than-temporary impairment, otherwise referred to herein as OTTI, as ASC Subtopic 326-30, Financial Instruments—Credit Losses—Available-for-Sale Debt Securities, changes the accounting for recognizing impairment on available-for-sale debt securities. Each quarter Management evaluates impairment where there has been a decline in fair value below the amortized cost basis of an available-for-sale security to determine whether there is a credit loss associated with the decline in fair value. Management considers the nature of the collateral, potential future changes in collateral values, default rates, delinquency rates, third-party guarantees, credit ratings, interest rate changes since purchase, volatility of the security’s fair value and historical loss information for financial assets secured with similar collateral among other factors. Credit losses are calculated individually, rather than collectively, using a discounted cash flow method, whereby Management compares the present value of expected cash flows with the amortized cost basis of the security. The credit loss component would be recognized through the provision for credit losses in the Statements of Income. Management excludes the accrued interest receivable balance from the amortized cost basis in measuring expected credit losses on the investment securities and does not record an allowance for credit losses on accrued interest receivable. As of December 31 2020, the accrued interest receivable for investment securities available-for-sale recorded in Other Assets was $13.1 million. ACL - Loans The ACL reflects Management’s estimate of losses that will result from the inability of our borrowers to make required loan payments. The Company established the incremental increase in the ACL at adoption through equity and subsequent adjustments through a provision for credit losses charged to earnings. The Company records loans charged off against the ACL and subsequent recoveries, if any, increase the ACL when they are recognized. Management uses systematic methodologies to determine its ACL for loans held for investment and certain off-balance-sheet credit exposures. The ACL is a valuation account that is deducted from the amortized cost basis to present the net amount expected to be collected on the loan portfolio. Management considers the effects of past events, current conditions, and reasonable and supportable forecasts on the collectability of the loan portfolio. The Company’s estimate of its ACL involves a high degree of judgment; therefore, Management’s process for determining expected credit losses may result in a range of expected credit losses. The Company’s ACL recorded in the balance sheet reflects Management’s best estimate within the range of expected credit losses. The Company recognizes in net income the amount needed to adjust the ACL for Management’s current estimate of expected credit losses. The Company’s ACL is calculated using collectively evaluated and individually evaluated loans. The Company merged with CSFL on June 7, 2020. For the second quarter ended June 30, 2020, given the proximity of the merger date to the quarter end, Management evaluated loans from each legacy loan portfolio utilizing pre-existing methodologies implemented prior to the merger and aggregated the result. During the third quarter, Management consolidated the two methodologies into one to arrive at the ACL recorded at December 31, 2020. The allowance for credit losses is measured on a collective pool basis when similar risk characteristics exist. Loans with similar risk characteristics are grouped into homogenous segments, or pools, for analysis. The Discounted Cash Flow (“DCF”) method is utilized for each loan in a pool, and the results are aggregated at the pool level. A periodic tendency to default and absolute loss given default are applied to a projective model of the loan’s cash flow while considering prepayment and principal curtailment effects. The analysis produces expected cash flows for each instrument in the pool by pairing loan-level term information (e.g., maturity date, payment amount, interest rate, etc.) with top-down pool assumptions (e.g., default rates and prepayment speeds). The Company has identified the following portfolio segments: Owner-Occupied Commercial Real Estate, Non Owner-Occupied Commercial Real Estate, Multifamily, Municipal, Commercial and Industrial, Commercial Construction and Land Development, Residential Construction, Residential Senior Mortgage, Residential Junior Mortgage, Revolving Mortgage, and Consumer and Other. In determining the proper level of the ACL, Management has determined that the loss experience of the Bank provides the best basis for its assessment of expected credit losses. It therefore utilized its own historical credit loss experience by each loan segment over an economic cycle, while excluding loss experience from certain acquired institutions (i.e., failed banks). For most of the segment models for collectively evaluated loans, the Company incorporated two or more macroeconomic drivers using a statistical regression modeling methodology. Management considers forward-looking information in estimating expected credit losses. The Company subscribes to a third-party service which provides a quarterly macroeconomic baseline outlook and alternative scenarios for the United States economy. The baseline, along with the evaluation of alternative scenarios, is used by Management to determine the best estimate within the range of expected credit losses. The baseline forecast incorporates a 50% probability of the United States economy performing better than this projection and the same as the probability that it will perform worse. Management has evaluated the appropriateness of the reasonable and supportable forecast scenarios and has made adjustments as needed. For the contractual term that extends beyond the reasonable and supportable forecast period, the Company reverts to the long term mean of historical factors within four quarters using a straight-line approach. The Company generally utilizes a four-quarter forecast and a four-quarter reversion period. Included in its systematic methodology to determine its ACL, Management considers the need to qualitatively adjust expected credit losses for information not already captured in the loss estimation process. These qualitative adjustments either increase or decrease the quantitative model estimation (i.e., formulaic model results). Each period the Company considers qualitative factors that are relevant within the qualitative framework that includes the following: 1) Lending Policy; 2) Economic conditions not captured in models; 3) Volume and Mix of Loan Portfolio; 4) Past Due Trends; 5) Concentration Risk; 6) External Factors; and 7) Model Limitations. When a loan no longer shares similar risk characteristics with its segment, the asset is assessed to determine whether it should be included in another pool or should be individually evaluated. The Company consolidated the ACL models and due to the size of the combined company, elected to increase the threshold for individually-evaluated loans to all non-accrual loans with a net book balance in excess of $1.0 million. Management will monitor the credit environment and make adjustments to this threshold in the future if warranted. Based on the threshold above, consumer financial assets will generally remain in pools unless they meet the dollar threshold. The expected credit losses on individually-evaluated loans will be estimated based on discounted cash flow analysis unless the loan meets the criteria for use of the fair value of collateral, either by virtue of an expected foreclosure or through meeting the definition of collateral-dependent. Financial assets that have been individually evaluated can be returned to a pool for purposes of estimating the expected credit loss insofar as their credit profile improves and that the repayment terms were not considered to be unique to the asset. Management measures expected credit losses over the contractual term of a loan. When determining the contractual term, the Company considers expected prepayments but is precluded from considering expected extensions, renewals, or modifications, unless the Company reasonably expects it will execute a troubled debt restructuring (“TDR”) with a borrower. In the event of a reasonably-expected TDR, the Company factors the reasonably-expected TDR into the current expected credit losses estimate. For consumer loans, the point at which a TDR is reasonably expected is when the Company approves the borrower’s application for a modification (i.e., the borrower qualifies for the TDR) or when the Credit Administration department approves loan concessions on substandard loans. For commercial loans, the point at which a TDR is reasonably expected is when the Company approves the loan for modification or when the Credit Administration department approves loan concessions on substandard loans. The Company uses a discounted cash flow methodology for a TDR to calculate the effect of the concession provided to the borrower within the ACL. A restructuring that results in only a delay in payments that is insignificant is not considered an economic concession. In accordance with the CARES Act, the Company implemented loan modification programs in response to the COVID-19 pandemic in order to provide borrowers with flexibility with respect to repayment terms. The Company’s payment relief assistance includes forbearance, deferrals, extension and re-aging programs, along with certain other modification strategies. The Company elected the accounting policy in the CARES Act to not apply TDR accounting to loans modified for borrowers impacted by the COVID-19 pandemic if the concession meets the criteria as defined under the CARES Act. or purchased credit-deteriorated, otherwise referred to herein as PCD, assets are defined as acquired individual financial assets (or acquired groups of financial assets with similar risk characteristics) that, as of the date of acquisition, have experienced a more-than-insignificant deterioration in credit quality since origination, as determined by the Company’s assessment. The Company records acquired PCD loans by adding the expected credit losses (i.e., allowance for credit losses) to the purchase price of the financial assets rather than recording through the provision for credit losses in the income statement. The expected credit loss, as of the acquisition day, of a PCD loan is added to the allowance for credit losses. The non-credit discount or premium is the difference between the unpaid principal balance and the amortized cost basis as of the acquisition date. Subsequent to the acquisition date, the change in the ACL on PCD loans is recognized through the provision for credit losses. The non-credit discount or premium is accreted or amortized, respectively, into interest income over the remaining life of the PCD loan on a level-yield basis. In accordance with the transition requirements within the standard, the Company’s acquired credit-impaired loans (i.e., ACI or Purchased Credit Impaired) were treated as PCD loans. The Company follows its nonaccrual policy by reversing contractual interest income in the income statement when the Company places a loan on nonaccrual status. Therefore, Management excludes the accrued interest receivable balance from the amortized cost basis in measuring expected credit losses on the portfolio and does not record an allowance for credit losses on accrued interest receivable. As of December 31, 2020, the accrued interest receivable for loans recorded in Other Assets was $93.9 million. The Company has a variety of assets that have a component that qualifies as an off-balance sheet exposure. These primarily include undrawn portions of revolving lines of credit and standby letters of credit. The expected losses associated with these exposures within the unfunded portion of the expected credit loss will be recorded as a liability on the balance sheet with an offsetting income statement expense. Management has determined that a majority of the Company’s off-balance-sheet credit exposures are not unconditionally cancellable. As part of the new combined ACL methodology implemented during 2020, Management completed a funding study based on historical data to estimate the percentage of unfunded loan commitments that will ultimately be funded to calculate the reserve for unfunded commitments. Management applied this funding rate, along with the loss factor rate determined for each pooled loan segment, to unfunded loan commitments, excluding unconditionally cancellable exposures and letters of credit, to arrive at the reserve for unfunded loan commitments. As of December 31, 2020, the liability recorded for expected credit losses on unfunded commitments was $43.4 million. The current adjustment to the ACL for unfunded commitments is recognized through the provision for credit losses in the Statements of Income. Other Real Estate Owned and Bank Property Held For Sale ​ Other real estate owned (“OREO”) consists of properties obtained through foreclosure or through a deed in lieu of foreclosure in satisfaction of loans. Prior to the merger with CSFL, the Company classified former branch sites as held for sale OREO. During the second quarter of 2020 and with the merger with CSFL, the Company elected to reclassify these assets as bank property held for sale and report on a separate line on the Consolidated Balance Sheet. Both OREO and bank property held for sale are recorded at the lower of cost or fair value and the fair value was determined on the basis of curr

Mergers and Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2020
Mergers and Acquisitions
Mergers and Acquisitions	Note 2—Mergers and Acquisitions CenterState Bank Corporation ​ On June 7, 2020, the Company acquired all of the outstanding common stock of CenterState Bank Corporation (“CSFL”), of Winter Haven, Florida, the bank holding company for CenterState Bank, N.A. (“CSB”), in a stock transaction. Pursuant to the Merger Agreement, (i) CSFL merged with and into the Company, with the Company continuing as the surviving corporation (the “Merger”), and (ii) immediately following the Merger, South State Bank (“SSB”), a South Carolina banking corporation and wholly owned bank subsidiary of the Company, merged with and into CSB, a national banking association and wholly owned bank subsidiary of CSFL, with CSB continuing as the surviving bank (the “Bank Merger”). In connection with the Bank Merger, CSB changed its name to “South State Bank, National Association” (hereinafter referred to as the “Bank”). CSFL common shareholders received shares of its common stock. In total, the purchase price for CSFL was recorded at million. Subsequently, during the fourth quarter, the purchase price (consideration transferred) decreased by million due to an update to the value for stock options assumed and converted in the merger. The stock options assumed reflect their intrinsic value based upon a Black Scholes valuation. ​ In the acquisition, the Company acquired $13.0 billion of loans, including PPP loans, at fair value, net of $239.5 million, or 1.82%, estimated discount, including a fair value adjustment of $29.8 million recorded during the third quarter, to the outstanding principal balance, representing 113.9% of the Company’s total loans at December 31, 2019. Of the total loans acquired, Management identified billion that had more than insignificantly deteriorated since origination and were thus determined to be PCD loans. ​ In its assumption of the deposit liabilities, the Company believed the deposits assumed from the acquisition have an intangible value. The Company applied ASC Topic 805, which prescribes the accounting for goodwill and other intangible assets such as core deposit intangibles, in a business combination. The Company determined the estimated fair value of the core deposit intangible asset totaled . In determining the valuation amount, deposits were analyzed based on factors such as type of deposit, deposit retention, interest rates and age of deposit relationships. During the third quarter, the Company identified an additional intangible related to its correspondent banking business acquired in the CSFL merger of approximately million. As a result of the various measurement period adjustments identified during the current year, goodwill was reduced by ​ During the year ended December 31, 2020, the Company incurred approximately $83.0 million of acquisition costs related to this transaction. There were no expenses incurred related to this acquisition for the year ended December 31, 2019. These acquisition costs are reported in merger and branch consolidation related expenses on the Company’s Consolidated Statements of Income. ​ The CSFL transaction was accounted for using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed and consideration exchanged were recorded at estimated fair value on the acquisition date. Fair values are preliminary and subject to refinement for up to a year after the closing date of the acquisition. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Initial ​ Subsequent ​ ​ ​ ​ ​ As Recorded ​ Fair Value ​ Fair Value ​ As Recorded by ​ (Dollars in thousands) by CSFL Adjustments Adjustments ​ the Company Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 2,566,450 ​ $ — ​ $ — ​ $ 2,566,450 ​ Investment securities ​ ​ 1,188,403 ​ ​ 5,507 (a) ​ — ​ ​ 1,193,910 ​ Loans held for sale ​ ​ 453,578 ​ ​ — ​ ​ — ​ ​ 453,578 ​ Loans, net of allowance and mark ​ 12,969,091 ​ (48,342) (b) ​ 29,834 (b) 12,950,583 ​ Premises and equipment ​ 308,150 ​ 2,392 (c) ​ 2,893 (c) 313,435 ​ Intangible assets ​ ​ 1,294,211 ​ ​ (1,163,349) (d) ​ 10,000 (d) ​ 140,862 ​ OREO and repossessed assets ​ ​ 10,849 ​ ​ (791) (e) ​ (49) (e) ​ 10,009 ​ Bank owned life insurance ​ ​ 333,053 ​ ​ — ​ ​ — ​ ​ 333,053 ​ Deferred tax asset ​ ​ 54,123 ​ ​ (8,681) (f) ​ (8,203) (f) ​ 37,239 ​ Other assets ​ 967,059 ​ (604) (g) ​ 642 (g) 967,097 ​ Total assets ​ $ 20,144,967 ​ $ (1,213,868) ​ $ 35,117 ​ $ 18,966,216 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Noninterest-bearing ​ $ 5,291,443 ​ $ — ​ $ — ​ $ 5,291,443 ​ Interest-bearing ​ 10,312,370 ​ 19,702 (h) ​ — ​ 10,332,072 ​ Total deposits ​ 15,603,813 ​ 19,702 ​ ​ — ​ 15,623,515 ​ Federal funds purchased and securities sold under agreements to repurchase ​ ​ 401,546 ​ ​ — ​ ​ — ​ ​ 401,546 ​ Other borrowings ​ ​ 278,900 ​ ​ (7,401) (i) ​ — ​ ​ 271,499 ​ Other liabilities ​ 977,725 ​ (4,592) (j) ​ 857 (j) 973,990 ​ Total liabilities ​ ​ 17,261,984 ​ ​ 7,709 ​ ​ 857 ​ ​ 17,270,550 ​ Net identifiable assets acquired over (under) liabilities assumed ​ ​ 2,882,983 ​ ​ (1,221,577) ​ ​ 34,260 ​ ​ 1,695,666 ​ Goodwill ​ — ​ 600,483 ​ ​ (39,441) ​ 561,042 ​ Net assets acquired over liabilities assumed ​ $ 2,882,983 ​ $ (621,094) ​ $ (5,181) ​ $ 2,256,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consideration: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ South State Corporation common shares issued ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 37,271,069 ​ Purchase price per share of the Company's common stock ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 60.27 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Company common stock issued ($2,246,327) and cash exchanged for fractional shares ($74) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,246,401 ​ Stock option conversion ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2,900 ​ Restricted stock conversion ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7,407 ​ Fair value of total consideration transferred ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,256,708 (k) ​ Explanation of fair value adjustments (a)— Represents the reversal of CSFL's existing fair value adjustments of $40.7 million and the adjustment to record securities at fair value (premium) totaling $46.2 million (includes reclassification of all securities held as HTM to AFS totaling $175.7 million). (b)— Represents approximately 2.04%, or $269.1 million, total mark of the loan portfolio including a 1.97%, or $259.7 million credit mark, based on a third party valuation. Also, includes the reversal of CSFL's ending allowance for credit losses of million. Fair value was subsequently adjusted by (c)— Represents the MTM adjustment of $4.0 million on leased assets partially offset by the write-off of de minimis fixed assets of $1.6 million. Subsequently, the fair value on certain bank premises was adjusted by (d)— Represents approximately a 1.28% core deposit intangible, or $125.9 million from a third party valuation. This amount is net of $84.9 million existing core deposit intangible and $1.2 billion of existing goodwill from CSFL’s prior transactions that was reversed. Approximately (e)— Represents the reversal of prior valuation reserves of $878,000 and recorded new valuation reserves of $1.7 million on both OREO and other repossessed assets. The fair value was subsequently adjusted based on gains and losses recognized from sales of OREO and other repossessed assets. (f)— Represents deferred tax assets related to fair value adjustments measured using an estimated tax rate of 22.0% . This includes an adjustment from the CSFL tax rate to our tax rate. The difference in tax rates relates to state income taxes. Additional deferred tax liability related to subsequent fair value adjustments identified and an updated estimated tax rate of (g)— Represents a valuation reserve of bank property held for sale of $3.2 million and a fair value adjustment of a lease receivable of $116,000. These amounts are offset by positive fair value adjustment for investment in low income housing of $3.3 million. (h)— Represents estimated premium for fixed maturity time deposits of $20.2 million partially offset by the reversal of existing CSFL fair value adjustments related to time deposit marks from other merger transactions of $546,000. (i)— Represents the recording of a discount of $12.5 million on TRUPs from a third party valuation partially offset by the reversal of the existing CSFL discount on TRUPs and other debt of $5.1 million. (j)— Represents the reversal of an existing $7.1 million unfunded commitment reserve at purchase date partially offset by a fair value adjustment to increase lease liabilities associated with leased facilities totaling $2.5 million. The discount rate applied to the bank owned life insurance split dollar liability was subsequently adjusted resulting in an increase in the other liability of $857,000. (k)—The purchase price, or the fair value of total consideration transferred, decreased by $5.2 million to $2.9 million for stock options assumed and converted in the merger. The stock options assumed reflect their intrinsic value based upon a Black Sholes valuation. Comparative and Pro Forma Financial Information for the CSFL Acquisition Pro-forma data for the years ended December 31, 2020 and 2019 listed in the table below presents pro-forma information as if the CSFL acquisition occurred at the beginning of 2019. These results combine the historical results of CSFL in the Company’s Consolidated Statements of Income and, while certain adjustments were made for the estimated impact of certain fair value adjustments and other acquisition-related activity, they are not indicative of what would have occurred had the acquisition taken place on January 1, 2019. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pro Forma ​ Pro Forma ​ ​ Year Ended ​ Year Ended (Dollars in thousands) ​ December 31, 2020 ​ December 31, 2019 Total revenues (net interest income plus noninterest income) $ 1,508,215 $ 1,368,452 Net interest income ​ $ 1,047,014 ​ $ 1,058,827 Net adjusted income available to the common shareholder ​ $ 385,390 ​ $ 412,515 EPS - basic ​ $ 5.44 ​ $ 5.85 EPS - diluted ​ $ 5.42 ​ $ 5.81 ​ Merger-related costs of $83.0 Million from the CSFL acquisition were incurred during 2020 and were excluded from pro forma information above. In addition, no adjustments have been made to the pro-formas to eliminate the provision for loan losses in 2019 of CSFL in the amount of million. Pro-forma data for the year 2020 eliminated the non-PCD provision recorded on the acquisition date of million. If the CSFL acquisition had occurred at the beginning of 2019, the acquisition date loan loss reserve amount would have been recorded directly through retained earnings upon adoption of ASU 2016-13 on January 1, 2020. No adjustments have been made to reduce the impact of any OREO write downs, investment securities sold or repayment of borrowings recognized by CSFL in either 2020 or 2019. Expenses related to systems conversions and other costs of integration are expected to be recorded during 2020 and 2021 for the CSFL merger. The Company expects to achieve further operating cost savings and other business synergies as a result of the acquisitions which are not reflected in the pro forma amounts above. The total revenues presented above represent pro-forma net interest income plus pro-forma noninterest income: The disclosures regarding the results of operations for CSFL subsequent to the acquisition date are omitted as this information is not practical to obtain. Although the Company has not converted CSFL’s core system, the majority of the fixed costs and purchase accounting entries were booked on the Company’s core system making it impractical to determine CSFL’s results of operation on a stand-alone basis.

Trading Securities

Trading Securities	12 Months Ended
	Dec. 31, 2020
Trading Securities
Trading Securities	Note 3—Trading Securities Realized and unrealized gains and losses are included in trading revenue, a component of noninterest income. Securities purchased for this portfolio have primarily been municipal securities. The trading portfolio is related to the Correspondent Banking Division that was acquired during the merger with CSFL on June 7, 2020. A list of the activity in this portfolio since June 7, 2020 is summarized below. ​ ​ ​ ​ ​ (Dollars in thousands) 2020 Beginning balance, June 7, 2020 ​ $ — Purchases ​ ​ 201,095 Proceeds from sale ​ ​ (190,907) Net realized gain on sales ​ 338 Net unrealized gains ​ 148 Ending balance ​ $ 10,674 ​

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2020
Investment Securities
Investment Securities	Note 4—Investment Securities The following is the amortized cost and fair value of investment securities held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Gross ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair (Dollars in thousands) Cost Gains Losses Value December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt* ​ $ 25,000 ​ $ 1 ​ $ — ​ $ 25,001 ​ Mortgage-backed securities** ​ ​ 930,542 ​ ​ 2,763 ​ ​ (1,123) ​ ​ 932,182 ​ ​ ​ $ 955,542 ​ $ 2,764 ​ $ (1,123) ​ $ 957,183 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State and municipal obligations ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ The following is the amortized cost and fair value of investment securities available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair (Dollars in thousands) Cost Gains Losses Value December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt* ​ $ 29,882 ​ $ 16 ​ $ (642) ​ $ 29,256 ​ State and municipal obligations ​ 502,575 ​ 17,491 ​ (27) ​ 520,039 ​ Mortgage-backed securities** ​ 2,722,018 ​ 49,153 ​ (3,496) ​ 2,767,675 ​ Corporate securities ​ ​ 13,562 ​ ​ 140 ​ ​ — ​ ​ 13,702 ​ ​ ​ $ 3,268,037 ​ $ 66,800 ​ $ (4,165) ​ $ 3,330,672 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt* ​ $ 25,356 ​ $ 585 ​ $ — ​ $ 25,941 ​ State and municipal obligations ​ 204,150 ​ 5,029 ​ (764) ​ 208,415 ​ Mortgage-backed securities** ​ 1,711,257 ​ 14,209 ​ (3,775) ​ 1,721,691 ​ ​ ​ $ 1,940,763 ​ $ 19,823 ​ $ (4,539) ​ $ 1,956,047 ​ * The Company’s government-sponsored entities holdings are comprised of debt securities offered by Federal Home Loan Mortgage Corporation (“FHLMC”) or Freddie Mac, Federal National Mortgage Association (“FNMA”) or Fannie Mae, FHLB, and Federal Farm Credit Banks (“FFCB”). ** All of the mortgage-backed securities are issued by government-sponsored entities; there are no private-label holdings. Also included in the Company’s government-sponsored entities are debt securities offered by the Small Business Administration (“SBA”), which have the full faith and credit backing of the United States Government. ​ The following is the amortized cost and carrying value of other investment securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying (Dollars in thousands) Value December 31, 2020: ​ ​ ​ ​ Federal Home Loan Bank stock ​ $ 15,083 ​ Federal Reserve Bank stock ​ ​ 129,871 ​ Investment in unconsolidated subsidiaries ​ 4,941 ​ Other nonmarketable investment securities ​ 10,548 ​ ​ ​ $ 160,443 ​ December 31, 2019: ​ ​ ​ ​ Federal Home Loan Bank stock ​ $ 43,044 ​ Investment in unconsolidated subsidiaries ​ 3,563 ​ Other nonmarketable investment securities ​ 2,517 ​ ​ ​ $ 49,124 ​ ​ The Company’s other investment securities consist of non-marketable equity securities that have no readily determinable market value. Accordingly, when evaluating these securities for impairment, management considers the ultimate recoverability of the par value rather than recognizing temporary declines in value. As of December 31, 2020, the Company has determined that there was no impairment on its other investment securities. The amortized cost and fair value of debt and equity securities at December 31, 2020 by contractual maturity are detailed below. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without prepayment penalties. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities ​ Securities ​ ​ Held-to-maturity ​ Available-for-sale ​ ​ Amortized ​ Fair ​ Amortized ​ Fair (Dollars in thousands) Cost Value Cost Value Due in one year or less $ — ​ $ — $ 9,669 $ 9,698 ​ Due after one year through five years ​ — ​ — ​ 80,846 ​ 83,586 ​ Due after five years through ten years ​ 88,735 ​ 89,007 ​ 525,547 ​ 539,905 ​ Due after ten years ​ 866,807 ​ 868,176 ​ 2,651,975 ​ 2,697,483 ​ ​ ​ $ 955,542 ​ $ 957,183 ​ $ 3,268,037 ​ $ 3,330,672 ​ ​ The following table summarizes information with respect to sales of available-for-sale securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2020 2019 2018 Securities Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sale proceeds $ 100,754 $ 242,733 $ 73,054 ​ Gross realized gains ​ ​ 662 ​ ​ 6,030 ​ ​ 31 ​ Gross realized losses ​ (612) ​ (3,319) ​ (686) ​ Net realized gain (loss) ​ $ 50 ​ $ 2,711 ​ $ (655) ​ ​ There was a net realized gain of $50,000 on the sale of securities for the year ended December 31, 2020, compared to a net realized gain of $2.7 million for the year ended December 31, 2019 and a net realized loss of $655,000 for the year ended December 31, 2018. The net realized gain of million from the sale of VISA Class B shares in the first and second quarters of 2019. If the gains from the VISA Class B share are excluded in 2019, the Company would have had a net realized loss of ​ There were no sales of held-to-maturity securities for years ended December 31, 2020, 2019 or 2018. ​ The Company had 86 securities with gross unrealized losses at December 31, 2020. Information pertaining to securities with gross unrealized losses at December 31, 2020 and 2019, aggregated by investment category and length of time that individual securities have been in a continuous loss position follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less Than ​ Twelve Months ​ ​ Twelve Months ​ or More ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ Fair ​ Unrealized ​ Fair (Dollars in thousands) Losses Value Losses Value December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Held-to-maturity ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities ​ $ 1,123 ​ $ 240,591 ​ $ — ​ $ — ​ ​ ​ $ 1,123 ​ $ 240,591 ​ $ — ​ $ — ​ Securities Available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ $ 642 ​ $ 24,358 ​ $ — ​ $ — ​ State and municipal obligations ​ 27 ​ 8,620 ​ — ​ — ​ Mortgage-backed securities ​ 2,475 ​ 509,319 ​ 1,021 ​ 105,125 ​ ​ ​ $ 3,144 ​ $ 542,297 ​ $ 1,021 ​ $ 105,125 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ $ — ​ $ — ​ $ — ​ $ — ​ State and municipal obligations ​ 764 ​ 42,070 ​ — ​ — ​ Mortgage-backed securities ​ 2,422 ​ 461,658 ​ 1,353 ​ 141,982 ​ ​ ​ $ 3,186 ​ $ 503,728 ​ $ 1,353 ​ $ 141,982 ​ ​ Management evaluates securities for impairment where there has been a decline in fair value below the amortized cost basis of a security to determine whether there is a credit loss associated with the decline in fair value on at least a quarterly basis, and more frequently when economic or market concerns warrant such evaluation. Credit losses are calculated individually, rather than collectively, using a discounted cash flow method, whereby Management compares the present value of expected cash flows with the amortized cost basis of the security. The credit loss component would be recognized through the provision for credit losses. Consideration is given to (1) the financial condition and near-term prospects of the issuer including looking at default and delinquency rates, (2) the outlook for receiving the contractual cash flows of the investments, (3) the length of time and the extent to which the fair value has been less than cost, (4) our intent and ability to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value or for a debt security whether it is more-likely-than-not that we will be required to sell the debt security prior to recovering its fair value, (5) the anticipated outlook for changes in the general level of interest rates, (6) credit ratings, (7) third party guarantees, and (8) collateral values. In analyzing an issuer’s financial condition, management considers whether the securities are issued by the federal government or its agencies, whether downgrades by bond rating agencies have occurred, the results of reviews of the issuer’s financial condition, and the issuer’s anticipated ability to pay the contractual cash flows of the investments. The Company performed an analysis that determined that the following securities have a zero expected credit loss: U.S. Treasury Securities, Agency-Backed Securities including securities issued by GNMA, FNMA, FHLB, FFCB and SBA. All of the U.S. Treasury and Agency-Backed Securities have the full faith and credit backing of the United State Government or one of its agencies. Municipal securities and all other securities that do not have a zero expected credit loss are evaluated quarterly to determine whether there is a credit loss associated with a decline in fair value. All debt securities in an unrealized loss position as of December 31, 2020 continue to perform as scheduled and we do not believe that there is a credit loss or that a provision for credit losses is necessary. Also, as part of our evaluation of our intent and ability to hold investments for a period of time sufficient to allow for any anticipated recovery in the market, we consider our investment strategy, cash flow needs, liquidity position, capital adequacy and interest rate risk position. We do not currently intend to sell the securities within the portfolio and it is not more-likely-than-not that we will be required to sell the debt securities. See Note 1—Summary of Significant Account Policies for further discussion Management continues to monitor all of our securities with a high degree of scrutiny. There can be no assurance that we will not conclude in future periods that conditions existing at that time indicate some or all of its securities may be sold or would require a charge to earnings as a provision for credit losses in such periods. At December 31, 2020 and 2019, investment securities with a carrying value of $2.1 billion and $726.1 million, respectively, were pledged to secure public funds deposits and for other purposes required and permitted by law. At December 31, 2020 and 2019, the carrying amount of the securities pledged to collateralize repurchase agreements was $515.9 million and $242.2 million, respectively.

Loans

Loans	12 Months Ended
	Dec. 31, 2020
Loans
Loans	Note 5—Loans The following is a summary of total loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2020 ​ 2019 Loans: ​ ​ ​ ​ ​ Construction and land development (1) ​ ​ $ 1,899,066 ​ $ 1,017,261 ​ Commercial non-owner occupied ​ ​ 5,931,323 ​ 2,323,967 ​ Commercial owner occupied real estate ​ ​ ​ 4,842,092 ​ ​ 2,158,701 ​ Consumer owner occupied (2) ​ ​ 4,108,042 ​ 2,706,960 ​ Home equity loans ​ ​ 1,336,689 ​ 758,020 ​ Commercial and industrial ​ ​ 5,047,147 ​ 1,386,327 ​ Other income producing property ​ ​ 587,448 ​ 346,554 ​ Consumer ​ ​ 894,334 ​ 663,422 ​ Other loans ​ ​ 17,993 ​ 13,892 ​ Total loans ​ ​ 24,664,134 ​ 11,375,104 ​ Less allowance for credit losses ​ ​ (457,309) ​ (61,991) ​ Loans, net ​ ​ $ 24,206,825 ​ $ 11,313,113 ​ (1) Construction and land development includes loans for both commercial construction and development, as well as loans for 1-4 family construction and lot loans. (2) Consumer owner occupied includes loans on both 1-4 family owner occupied property, as well as 1-4 family investment rental property. ​ In accordance with the adoption of ASU 2016-13, the above table reflects the loan portfolio at the amortized cost basis for the year ended December 31, 2020, to include net deferred fees of $35.6 million and unamortized discount total related to loans acquired of $97.7 million. Accrued interest receivable (AIR) of $93.9 million is accounted for separately and reported in other assets. The allowance for credit losses in the comparative periods includes the day 2 valuation allowance on the acquired credit impaired loans, which was $5.1 million at December 31, 2019. ​ The comparative periods in the above table reflect the loan portfolio prior to the adoption of ASU 2016-13. Prior periods were reported as shown in the below tables, with the acquired loans being net of unearned income and of related discounts, which includes the credit discount on the acquired credit impaired loans. ​ The following is a summary of non-acquired loans for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Non-acquired loans: ​ ​ ​ Commercial non-owner occupied real estate: ​ ​ ​ ​ Construction and land development ​ $ 968,360 ​ Commercial non-owner occupied ​ 1,811,138 ​ Total commercial non-owner occupied real estate ​ 2,779,498 ​ Consumer real estate: ​ ​ ​ ​ Consumer owner occupied ​ 2,118,839 ​ Home equity loans ​ 518,628 ​ Total consumer real estate ​ 2,637,467 ​ Commercial owner occupied real estate ​ 1,784,017 ​ Commercial and industrial ​ 1,280,859 ​ Other income producing property ​ 218,617 ​ Consumer ​ 538,481 ​ Other loans ​ 13,892 ​ Total non-acquired loans ​ 9,252,831 ​ Less allowance for loan losses ​ (56,927) ​ Non-acquired loans, net ​ $ 9,195,904 ​ ​ The following is a summary of acquired non-credit impaired loans accounted for under FASB ASC Topic 310-20, net of related discount, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Acquired non-credit impaired loans: ​ ​ ​ Commercial non-owner occupied real estate: ​ ​ ​ ​ Construction and land development ​ $ 33,569 ​ Commercial non-owner occupied ​ 447,441 ​ Total commercial non-owner occupied real estate ​ 481,010 ​ Consumer real estate: ​ ​ ​ ​ Consumer owner occupied ​ 496,431 ​ Home equity loans ​ 188,732 ​ Total consumer real estate ​ 685,163 ​ Commercial owner occupied real estate ​ 307,193 ​ Commercial and industrial ​ 101,880 ​ Other income producing property ​ 95,697 ​ Consumer ​ 89,484 ​ Acquired non-credit impaired loans ​ $ 1,760,427 ​ ​ ​ 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, ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Acquired credit impaired loans: ​ ​ ​ Commercial real estate ​ $ 130,938 ​ Commercial real estate—construction and development ​ 25,032 ​ Residential real estate ​ 163,359 ​ Consumer ​ 35,488 ​ Commercial and industrial ​ 7,029 ​ Acquired credit impaired loans ​ 361,846 ​ Less allowance for loan losses ​ (5,064) ​ Acquired credit impaired loans, net ​ $ 356,782 ​ ​ The Company has purchased loans through its acquisition of CSFL, for which there was, at acquisition, evidence of more than insignificant deterioration of credit quality since origination. The carrying amount of those loan, at acquisition, is as follows: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ June 7, 2020 ​ Book value of acquired loans at acquisition ​ $ 3,091,264 ​ Allowance for credit losses at acquisition ​ (149,404) ​ Non-credit discount at acquisition ​ (14,283) ​ Carrying value or book value of acquired loans at acquisition ​ $ 2,927,577 ​ ​ ​ ​ The following three tables are presented for comparative periods, prior to the adoption of ASU 2016-13, in which accounting rules were different, therefore unrelated to the current reporting period: ​ Contractual loan payments receivable, estimates of amounts not expected to be collected, other fair value adjustments and the resulting carrying values of total acquired credit impaired loans as of December 31, 2019 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ Contractual principal and interest ​ ​ $ 452,818 Non-accretable difference ​ ​ (13,938) ​ Cash flows expected to be collected ​ ​ 438,880 ​ Accretable yield ​ ​ (82,098) ​ Carrying value ​ ​ $ 356,782 ​ ​ 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: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2019 Balance at beginning of period ​ $ 485,119 ​ Net reductions for payments, foreclosures, and accretion ​ (127,877) ​ Change in the allowance for loan losses on acquired loans ​ (460) ​ Balance at end of period, net of allowance for loan losses on acquired credit impaired loans ​ $ 356,782 ​ ​ The following are changes in the carrying amount of accretable yield for acquired credit impaired loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2019 2018 Balance at beginning of period ​ $ 116,754 ​ $ 133,096 ​ Addition from the PSC acquisition ​ ​ — ​ ​ — ​ Park Sterling Corporation ("Park Sterling") acquisition Day 1 adjustment ​ ​ — ​ ​ (1,460) ​ Contractual interest income ​ (26,515) ​ (33,115) ​ Accretion on acquired credit impaired loans ​ ​ (17,813) ​ ​ (19,004) ​ Reclass of nonaccretable difference due to improvement in expected cash flows ​ 9,826 ​ 37,501 ​ Other changes, net ​ (154) ​ (264) ​ Balance at end of period ​ $ 82,098 ​ $ 116,754 ​ ​ 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 each year. In 2019, the accretable yield balance declined by $34.7 million as total contractual interest and accretion income of $44.3 million was recognized. This was partially offset by improved expected cash flows of $9.8 million. The improved cash flows for previous years were adjusted to accurately reflect the split between income types. ​ As of December 31, 2019, the table above excludes $1.8 billion ($1.8 billion in contractual principal less a $20.3 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 the credit or as a revolving lines of credit (commercial or consumer) at acquisition. As of December 31, 2018, the balance of these acquired loans totaled $2.6 billion ($2.6 billion in contractual principal less a $33.4 million remaining discount). 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. ​ The Company utilizes a risk grading matrix to assign a risk grade to each commercial loan. Classified loans are assessed at a minimum every six months. A description of the general characteristics of the risk grades is as follows: • • 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. ​ Construction and land development loans in the following table are on commercial and speculative real estate. Consumer owner occupied loans are on investment or rental 1-4 properties. ​ ​ The following table presents the credit risk profile by risk grade of commercial loans by origination year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loans ​ ​ (Dollars in thousands) Amortized Cost Basis by Origination Year ​ ​ As of December 31, 2020 2020 2019 2018 2017 2016 Prior Revolving Total Construction and land development ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 457,433 $ 410,075 $ 133,719 $ 79,345 $ 41,018 $ 53,104 $ 15,502 $ 1,190,196 Special mention 20,912 5,668 707 1,757 1,815 7,293 - 38,152 Substandard 389 2,800 763 2,087 201 3,669 - 9,909 Doubtful - - - - - 8 - 8 Total Construction and land development $ 478,734 $ 418,543 $ 135,189 $ 83,189 $ 43,034 $ 64,074 $ 15,502 $ 1,238,265 ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial non-owner occupied ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 799,175 $ 1,082,242 $ 844,988 $ 661,092 $ 676,895 $ 1,196,156 $ 58,021 $ 5,318,569 Special mention 42,492 76,890 111,466 44,790 38,637 131,015 - 445,290 Substandard 1,351 49,662 7,497 27,224 38,617 43,109 - 167,460 Doubtful - - - - - 4 - 4 Total Commercial non-owner occupied $ 843,018 $ 1,208,794 $ 963,951 $ 733,106 $ 754,149 $ 1,370,284 $ 58,021 $ 5,931,323 ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial Owner Occupied ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 805,192 $ 957,412 $ 721,808 $ 603,785 $ 458,065 $ 1,042,755 $ 42,239 $ 4,631,256 Special mention 6,993 15,984 13,021 14,457 13,597 48,775 21 112,848 Substandard 5,729 4,185 4,690 20,122 15,093 48,127 36 97,982 Doubtful 1 - - - - 5 - 6 Total commercial owner occupied $ 817,915 $ 977,581 $ 739,519 $ 638,364 $ 486,755 $ 1,139,662 $ 42,296 $ 4,842,092 ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial and industrial ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 2,723,320 $ 595,310 $ 450,238 $ 308,914 $ 223,532 $ 419,555 $ 247,169 $ 4,968,038 Special mention 1,566 3,273 3,031 7,243 2,496 25,727 9,368 52,704 Substandard 347 1,070 6,202 7,718 2,808 6,010 2,240 26,395 Doubtful - 2 1 3 3 1 ​ 10 Total commercial and industrial $ 2,725,233 $ 599,655 $ 459,472 $ 323,878 $ 228,839 $ 451,293 $ 258,777 $ 5,047,147 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other income producing property ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 95,530 $ 89,648 $ 75,301 $ 55,103 $ 66,351 $ 121,304 $ 6,487 $ 509,724 Special mention 2,613 1,417 1,702 235 879 11,202 100 18,148 Substandard 1,071 1,046 997 19 1,279 13,702 47 18,161 Doubtful - - - - - 6 - 6 Total other income producing property $ 99,214 $ 92,111 $ 78,000 $ 55,357 $ 68,509 $ 146,214 $ 6,634 $ 546,039 ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer owner occupied ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 7,590 $ 3,527 $ 356 $ 339 $ 1,076 $ 1,290 $ 15,502 $ 29,680 Special mention 130 3,581 249 62 - 124 338 4,484 Substandard 113 387 142 - 5 326 - 973 Doubtful - - - - - - - - Total Consumer owner occupied $ 7,833 $ 7,495 $ 747 $ 401 $ 1,081 $ 1,740 $ 15,840 $ 35,137 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other loans ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 17,993 $ - $ - $ - $ - $ - $ - $ 17,993 Special mention - - - - - - - - Substandard - - - - - - - - Doubtful - - - - - - - - Total other loans $ 17,993 $ - $ - $ - $ - $ - $ - $ 17,993 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Commercial Loans ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 4,906,233 $ 3,138,214 $ 2,226,410 $ 1,708,578 $ 1,466,937 $ 2,834,164 $ 384,920 $ 16,665,456 Special mention 74,706 106,813 130,176 68,544 57,424 224,136 9,827 671,626 Substandard 9,000 59,150 20,291 57,170 58,003 114,943 2,323 320,880 Doubtful 1 2 1 3 3 24 - 34 Total Commercial Loans $ 4,989,940 $ 3,304,179 $ 2,376,878 $ 1,834,295 $ 1,582,367 $ 3,173,267 $ 397,070 $ 17,657,996 ​ For the consumer segment, delinquency of a loan is determined by past due status. Consumer loans are automatically placed on nonaccrual status once the loan is 90 days past due. Construction and land development loans are on 1-4 properties and lots. The following table presents the credit risk profile by past due status of consumer loans by origination year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loans ​ ​ (Dollars in thousands) Amortized Cost Basis by Origination Year ​ ​ As of December 31, 2020 2020 2019 2018 2017 2016 Prior Revolving Total Consumer owner occupied ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 810,215 $ 675,928 $ 543,711 $ 508,160 $ 392,754 $ 1,097,008 $ - $ 4,027,776 30 days past due 4,933 7,744 2,816 2,382 3,510 10,522 - 31,907 60 days past due - 350 1,222 621 103 3,068 - 5,364 90 days past due - 176 264 994 875 5,549 - 7,858 Total Consumer owner occupied $ 815,148 $ 684,198 $ 548,013 $ 512,157 $ 397,242 $ 1,116,147 $ - $ 4,072,905 ​ ​ ​ ​ ​ ​ ​ ​ ​ Home equity loans ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 7,654 $ 6,694 $ 7,670 $ 658 $ 398 $ 30,039 $ 1,276,058 $ 1,329,171 30 days past due 134 52 - 79 - 272 2,324 2,861 60 days past due - - - - - 116 418 534 90 days past due 155 93 - 157 330 1,886 1,502 4,123 Total Home equity loans $ 7,943 $ 6,839 $ 7,670 $ 894 $ 728 $ 32,313 $ 1,280,302 $ 1,336,689 ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 291,305 $ 201,330 $ 115,203 $ 62,485 $ 38,272 $ 147,101 $ 32,874 $ 888,570 30 days past due 105 473 454 224 29 1,043 23 2,351 60 days past due 68 143 93 61 37 376 47 825 90 days past due 73 195 272 185 100 1,663 100 2,588 Total consumer $ 291,551 $ 202,141 $ 116,022 $ 62,955 $ 38,438 $ 150,183 $ 33,044 $ 894,334 ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 370,975 $ 164,260 $ 63,936 $ 18,530 $ 4,497 $ 25,399 $ - $ 647,597 30 days past due 6,172 3,660 161 - 2,255 184 - 12,432 60 days past due 282 - 438 - - - - 720 90 days past due - - - - - 52 - 52 Total Construction and land development $ 377,429 $ 167,920 $ 64,535 $ 18,530 $ 6,752 $ 25,635 $ - $ 660,801 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other income producing property ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 1,412 $ 1,351 $ 1,310 $ 3,658 $ 2,045 $ 31,592 $ - $ 41,368 30 days past due - - - - - 27 - 27 60 days past due - - - - - 13 - 13 90 days past due - - - - - 1 - 1 Total other income producing property $ 1,412 $ 1,351 $ 1,310 $ 3,658 $ 2,045 $ 31,633 $ - $ 41,409 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Consumer Loans ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 1,481,561 $ 1,049,563 $ 731,830 $ 593,491 $ 437,966 $ 1,331,139 $ 1,308,932 $ 6,934,482 30 days past due 11,344 11,929 3,431 2,685 5,794 12,048 2,347 49,578 60 days past due 350 493 1,753 682 140 3,573 465 7,456 90 days past due 228 464 536 1,336 1,305 9,151 1,602 14,622 Total Consumer Loans $ 1,493,483 $ 1,062,449 $ 737,550 $ 598,194 $ 445,205 $ 1,355,911 $ 1,313,346 $ 7,006,138 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loans ​ ​ (Dollars in thousands) Amortized Cost Basis by Origination Year ​ ​ As of December 31, 2020 2020 2019 2018 2017 2016 Prior Revolving Total Total Loans $ 6,483,423 $ 4,366,628 $ 3,114,428 $ 2,432,489 $ 2,027,572 $ 4,529,178 $ 1,710,416 $ 24,664,134 ​ ​ ​ The following table presents the credit risk profile by risk grade of commercial loans for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction & Development ​ Commercial Non-owner Occupied ​ Commercial Owner Occupied ​ ​ December 31, ​ December 31, ​ December 31, (Dollars in thousands) 2019 2019 2019 Pass ​ $ 959,206 ​ $ 1,787,306 ​ $ 1,754,801 Special mention ​ 7,095 ​ 22,410 ​ 19,742 Substandard ​ 2,059 ​ 1,422 ​ 9,474 Doubtful ​ — ​ — ​ — ​ ​ $ 968,360 ​ $ 1,811,138 ​ $ 1,784,017 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial & Industrial ​ Other Income Producing Property ​ Commercial Total ​ ​ December 31, ​ December 31, ​ December 31, ​ 2019 2019 2019 Pass ​ $ 1,256,465 ​ $ 213,291 ​ $ 5,971,069 ​ Special mention ​ 16,055 ​ 3,966 ​ 69,268 ​ Substandard ​ 8,339 ​ 1,360 ​ 22,654 ​ Doubtful ​ — ​ — ​ — ​ ​ ​ $ 1,280,859 ​ $ 218,617 ​ $ 6,062,991 ​ ​ The following table presents the credit risk profile by risk grade of consumer loans for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer Owner Occupied ​ Home Equity ​ Consumer ​ ​ December 31, ​ December 31, ​ December 31, (Dollars in thousands) 2019 2019 2019 Pass ​ $ 2,094,080 ​ $ 508,054 ​ $ 536,002 Special mention ​ 9,585 ​ 4,490 ​ 487 Substandard ​ 15,174 ​ 6,084 ​ 1,992 Doubtful ​ — ​ — ​ — ​ ​ $ 2,118,839 ​ $ 518,628 ​ $ 538,481 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ Consumer Total ​ December 31, 2019 December 31, 2019 Pass ​ $ 13,892 ​ $ 3,152,028 Special mention ​ — ​ 14,562 Substandard ​ — ​ 23,250 Doubtful ​ — ​ — ​ ​ $ 13,892 ​ $ 3,189,840 ​ ​ The following table presents the credit risk profile by risk grade of total non-acquired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ Total Non-acquired Loans ​ ​ December 31, (Dollars in thousands) 2019 Pass ​ $ 9,123,097 Special mention ​ 83,830 Substandard ​ 45,904 Doubtful ​ — ​ ​ $ 9,252,831 ​ ​ The following table presents the credit risk profile by risk grade of commercial loans for acquired non-credit impaired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction & Development ​ ​ Commercial Non-owner Occupied ​ ​ Commercial Owner Occupied ​ ​ December 31, ​ ​ December 31, ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ 2019 ​ 2019 Pass ​ $ 31,690 ​ $ 432,710 $ 300,678 ​ Special mention ​ 966 ​ 14,162 ​ 3,092 ​ Substandard ​ 913 ​ 569 ​ 3,423 ​ Doubtful ​ — ​ — ​ — ​ ​ ​ $ 33,569 ​ $ 447,441 ​ $ 307,193 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other Income Producing ​ ​ ​ ​ ​ ​ Commercial & Industrial ​ Property ​ Commercial Total ​ ​ December 31, ​ ​ December 31, ​ December 31, ​ 2019 ​ 2019 ​ 2019 Pass ​ $ 97,092 $ 87,892 $ 950,062 Special mention ​ 2,948 ​ 5,837 ​ 27,005 Substandard ​ 1,840 ​ 1,968 ​ 8,713 Doubtful ​ — ​ — ​ — ​ ​ $ 101,880 ​ $ 95,697 ​ $ 985,780 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table presents the credit risk profile by risk grade of consumer loans for acquired non-credit impaired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer Owner Occupied ​ Home Equity ​ ​ Consumer ​ ​ December 31, ​ December 31, ​ ​ December 31, (Dollars in thousands) ​ 2019 ​ 2019 ​ ​ 2019 Pass $ 486,433 $ 174,912 $ 86,535 Special mention ​ 6,434 ​ 5,679 ​ ​ 654 Substandard ​ 3,564 ​ 8,141 ​ ​ 2,295 Doubtful ​ — ​ — ​ ​ — ​ ​ $ 496,431 ​ $ 188,732 ​ ​ $ 89,484 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer Total ​ ​ ​ December 31, (Dollars in thousands) ​ ​ 2019 Pass ​ $ 747,880 Special mention ​ ​ 12,767 Substandard ​ ​ 14,000 Doubtful ​ ​ — ​ ​ ​ $ 774,647 ​ ​ ​ ​ The following table presents the credit risk profile by risk grade of total acquired non-credit impaired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ Total Acquired ​ ​ ​ Non-credit Impaired Loans ​ ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ Pass ​ $ 1,697,942 Special mention ​ 39,772 ​ Substandard ​ 22,713 ​ Doubtful ​ — ​ ​ ​ $ 1,760,427 ​ ​ 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 for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial Real Estate— ​ ​ ​ ​ Construction and ​ Commercial Real Estate ​ Development ​ ​ December 31, ​ ​ December 31, (Dollars in thousands) 2019 ​ 2019 Pass ​ $ 108,762 $ 17,756 ​ Special mention ​ 6,465 ​ 2,904 ​ Substandard ​ 15,711 ​ 4,372 ​ Doubtful ​ — ​ — ​ ​ ​ $ 130,938 ​ $ 25,032 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Residential Real Estate ​ Consumer ​ Commercial & Industrial ​ December 31, ​ December 31, ​ December 31, ​ 2019 2019 2019 Pass $ 82,203 ​ $ 4,483 ​ $ 5,160 ​ Special mention 35,968 ​ 12,658 ​ 286 ​ Substandard 45,188 ​ 18,347 ​ 1,583 ​ Doubtful — ​ — ​ — ​ ​ $ 163,359 ​ $ 35,488 ​ $ 7,029 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Acquired ​ ​ ​ Credit Impaired Loans ​ ​ ​ ​ December 31, ​ ​ 2019 Pass ​ $ 218,364 ​ Special mention ​ ​ 58,281 ​ Substandard ​ ​ 85,201 ​ Doubtful ​ ​ — ​ ​ ​ ​ $ 361,846 ​ ​ 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 accruing loans, segregated by class: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ ​ ​ ​ Total (Dollars in thousands) Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Non-Accruing ​ Loans December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development $ 520 ​ $ 1,142 ​ $ — ​ $ 1,662 ​ $ 1,894,983 ​ $ 2,421 ​ $ 1,899,066 Commercial non-owner occupied 188 ​ 372 ​ 471 ​ 1,031 ​ 5,925,696 ​ 4,596 ​ 5,931,323 Commercial owner occupied 2,900 ​ ​ 840 ​ — ​ 3,740 ​ 4,812,293 ​ 26,059 ​ 4,842,092 Consumer owner occupied 1,375 ​ 3,632 ​ 34 ​ 5,041 ​ 4,072,255 ​ 30,746 ​ 4,108,042 Home equity loans 1,805 ​ 481 ​ — ​ 2,286 ​ 1,324,459 ​ 9,944 ​ 1,336,689 Commercial and industrial 10,979 ​ 22,089 ​ 10,864 ​ 43,932 ​ 4,993,997 ​ 9,218 ​ 5,047,147 Other income producing property 687 ​ — ​ 278 ​ 965 ​ 580,353 ​ 6,130 ​ 587,448 Consumer 1,718 ​ 818 ​ 4 ​ 2,540 ​ 885,720 ​ 6,074 ​ 894,334 Other loans 13 ​ 6 ​ — ​ 19 ​ 17,974 ​ — ​ 17,993 ​ $ 20,185 ​ $ 29,380 ​ $ 11,651 ​ $ 61,216 ​ $ 24,507,730 ​ $ 95,188 ​ $ 24,664,134 ​ The following table presents an aging analysis of past due accruing loans, segregated by class for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ Total (Dollars in thousands) ​ Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Loans December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development ​ $ 321 ​ $ 39 ​ $ 255 ​ $ 615 ​ $ 967,745 ​ $ 968,360 Commercial non-owner occupied ​ 114 ​ — ​ 299 ​ 413 ​ 1,810,725 ​ 1,811,138 Commercial owner occupied ​ 4,011 ​ 636 ​ 2,302 ​ 6,949 ​ 1,777,068 ​ 1,784,017 Consumer real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer owner occupied ​ 1,157 ​ 285 ​ 2,424 ​ 3,866 ​ 2,114,973 ​ 2,118,839 Home equity loans ​ 1,343 ​ 39 ​ 562 ​ 1,944 ​ 516,684 ​ 518,628 Commercial and industrial ​ 5,531 ​ 100 ​ 649 ​ 6,280 ​ 1,274,579 ​ 1,280,859 Other income producing property ​ 208 ​ — ​ 457 ​ 665 ​ 217,952 ​ 218,617 Consumer ​ 825 ​ 285 ​ 826 ​ 1,936 ​ 536,545 ​ 538,481 Other loans ​ 25 ​ 3 ​ — ​ 28 ​ 13,864 ​ 13,892 ​ ​ $ 13,535 ​ $ 1,387 ​ $ 7,774 ​ $ 22,696 ​ $ 9,230,135 ​ $ 9,252,831 ​ The following table presents an aging analysis of past due accruing loans, segregated by class for acquired non-credit impaired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ Total (Dollars in thousands) ​ Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Loans December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development ​ $ 20 ​ $ — ​ $ 256 ​ $ 276 ​ $ 33,293 ​ $ 33,569 Commercial non-owner occupied ​ 144 ​ 1,146 ​ 76 ​ 1,366 ​ 446,075 ​ 447,441 Commercial owner occupied ​ 890 ​ 702 ​ 698 ​ 2,290 ​ 304,903 ​ 307,193 Consumer real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer owner occupied ​ 768 ​ 151 ​ 414 ​ 1,333 ​ 495,098 ​ 496,431 Home equity loans ​ 369 ​ 55 ​ 1,154 ​ 1,578 ​ 187,154 ​ 188,732 Commercial and industrial ​ 93 ​ 204 ​ 17 ​ 314 ​ 101,566 ​ 101,880 Other income producing property ​ 378 ​ 4,309 ​ 551 ​ 5,238 ​ 90,459 ​ 95,697 Consumer ​ 485 ​ 613 ​ 423 ​ 1,521 ​ 87,963 ​ 89,484 ​ ​ $ 3,147 ​ $ 7,180 ​ $ 3,589 ​ $ 13,916 ​ $ 1,746,511 ​ $ 1,760,427 ​ The following table presents an aging analysis of past due accruing loans, segregated by class for acquired credit impaired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ Total (Dollars in thousands) ​ Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Loans December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial real estate ​ $ 2,283 ​ $ — ​ $ 2,659 ​ $ 4,942 ​ $ 125,996 ​ $ 130,938 Commercial real estate—construction and development ​ — ​ — ​ 393 ​ 393 ​ 24,639 ​ 25,032 Residential real estate ​ 2,838 ​ 976 ​ 5,571 ​ 9,385 ​ 153,974 ​ 163,359 Consumer ​ 820 ​ 283 ​ 534 ​ 1,637 ​ 33,851 ​ 35,488 Commercial and industrial ​ 118 ​ 910 ​ 75 ​ 1,103 ​ 5,926 ​ 7,029 ​ ​ $ 6,059 ​ $ 2,169 ​ $ 9,232 ​ $ 17,460 ​ $ 344,386 ​ $ 361,846 ​ ​ The following is a summary of information pertaining to nonaccrual loans by class, including restructured loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ Greater than ​ Non-accrual ​ ​ (Dollars in thousands) 2019 2020 ​ 90 Days Accruing (1) with no allowance (1) Construction and land development ​ $ 1,193 ​ $ 2,421 ​ $ — ​ $ 533 ​ ​ Commercial non-owner occupied ​ 1,154 ​ 4,596 ​ ​ 471 ​ — ​ ​ Commercial owner occupied real estate ​ 4,385 ​ 26,059 ​ ​ — ​ 9,351 ​ ​ Consumer owner occupied ​ 9,718 ​ 30,746 ​ ​ 34 ​ 383 ​ ​ Home equity loans ​ 4,640 ​ 9,944 ​ ​ — ​ 52 ​ ​ Commercial and industrial ​ 6,913 ​ 9,218 ​ ​ 10,864 ​ 585 ​ ​ Other income producing property ​ 1,947 ​ 6,130 ​ ​ 278 ​ 349 ​ ​ Consumer ​ 3,191 ​ 6,074 ​ ​ 4 ​ — ​ ​ Total loans on nonaccrual status ​ $ 33,141 ​ $ 95,188 ​ $ 11,651 ​ $ 11,253 ​ ​ (1) ​ There is no interest income recognized during the period on nonaccrual loans. The Company follows its nonaccrual policy by reversing contractual interest income in the income statement when the Company places a loan on nonaccrual status. Loans on nonaccrual status in which there is no allowance assigned are individually evaluated loans that do not carry a specific reserve. See Note 1 — Summary of Significant Accounting Policies for further detailed on individually evaluated loans. The increase in the nonaccrual balance in the above schedule, compared to December 31, 2019, is mainly due to the addition of nonaccrual loans of million through the merger with CSFL in the second quarter. The increase was also partially due to the addition of million of PCD loans, formerly accounted for as credit impaired loans, prior to the adoption of ASU 2016-13. These loans were previously excluded from nonaccrual loans. ​ The following is a summary of information pertaining to non-acquired nonaccrual loans by class, including restructured loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Commercial non-owner occupied real estate: ​ ​ ​ ​ ​ Construction and land development ​ ​ $ 363 ​ Commercial non-owner occupied ​ ​ 732 ​ Total commercial non-owner occupied real estate ​ ​ 1,095 ​ Consumer real estate: ​ ​ ​ ​ ​ Consumer owner occupied ​ ​ 7,202 ​ Home equity loans ​ ​ 1,468 ​ Total consumer real estate ​ ​ 8,670 ​ Commercial owner occupied real estate ​ ​ 3,482 ​ Commercial and industrial ​ ​ 4,092 ​ Other income producing property ​ ​ 798 ​ Consumer ​ ​ 1,587 ​ Restructured loans ​ ​ 2,578 ​ Total loans on nonaccrual status ​ ​ $ 22,302 ​ ​ ​ The following is a summary of information pertaining to acquired non-credit impaired nonaccrual loans by class, including restructured loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Commercial non-owner occupied real estate: ​ ​ ​ Construction and land development ​ $ 699 Commercial non-owner occupied ​ ​ 393 Total commercial non-owner occupied real estate ​ ​ 1,092 Consumer real estate: ​ ​ ​ Consumer owner occupied ​ ​ 2,350 Home equity loans ​ ​ 3,067 Total consumer real estate ​ ​ 5,417 Commercial owner occupied real estate ​ ​ 903 Commercial and industrial ​ ​ 722 Other income producing property ​ ​ 1,101 Consumer ​ ​ 1,604 Total loans on nonaccrual status ​ $ 10,839 ​ The following is a summary of collateral dependent loans, by type of collateral, and the extent to which they are collateralized during the period: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ Collateral ​ ​ December 31, ​ Collateral ​ ​ (Dollars in thousands) 2019 Coverage % ​ 2020 Coverage % ​ Commercial non-owner occupied ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Church ​ $ 245 ​ $ 846 345% ​ $ — ​ $ — ​ ​ Office ​ ​ 1,045 ​ ​ 1,800 172% ​ ​ — ​ ​ — ​ ​ Other ​ ​ 398 ​ ​ 648 163% ​ ​ — ​ ​ — ​ ​ Retail ​ ​ 299 ​ ​ 1,269 424% ​ ​ — ​ ​ — ​ ​ Commercial owner occupied real estate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Church ​ ​ — ​ ​ — ​ ​ ​ — ​ ​ — ​ ​ Industrial ​ ​ 738 ​ ​ 1,103 149% ​ ​ — ​ ​ — ​ ​ Office ​ ​ 1,076 ​ ​ 1,485 138% ​ ​ 1,076 ​ ​ 1,485 138% ​ Retail ​ ​ — ​ ​ — ​ ​ ​ 4,849 ​ ​ 5,490 113% ​ Other ​ ​ 3,303 ​ ​ 7,285 221% ​ ​ 1,010 ​ ​ 1,075 106% ​ Consumer owner occupied ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 5,413 ​ ​ 9,286 172% ​ ​ — ​ ​ — ​ ​ Home equity loans ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 1,768 ​ ​ 2,679 152% ​ ​ — ​ ​ — ​ ​ Commercial and industrial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Industrial ​ ​ 291 ​ ​ 702 241% ​ ​ — ​ ​ — ​ ​ Other ​ ​ 3,696 ​ ​ 8,442 228% ​ ​ — ​ ​ — ​ ​ Other income producing property ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 3,212 ​ ​ 10,186 317% ​ ​ — ​ ​ — ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 363 ​ ​ 525 145% ​ ​ — ​ ​ — ​ ​ Total collateral dependent loans ​ $ 21,847 ​ $ 46,256 ​ ​ $ 6,935 ​ $ 8,050 ​ ​ ​ The Bank designates individually evaluated loans (excluding TDRs) on non-accrual with a net book balance exceeding the designated threshold as collateral dependent loans. Collateral dependent loans are loans for which the repayment is expected to be provided substantially through the operation or sale of the collateral and the borrower is experiencing financial difficulty. These loans do not share common risk characteristics and are not included within the collectively evaluated loans for determining ACL. Under ASC 326-20-35-6, the Bank has adopted the collateral maintenance practical expedient to measure the ACL based on the fair value of collateral. The ACL is calculated on an individual loan basis based on the shortfall between the fair value of the loan's collateral, which is adjusted for selling costs, and amortized cost. If the fair value of the collater

Allowance for Credit Losses (AC

Allowance for Credit Losses (ACL)	12 Months Ended
	Dec. 31, 2020
Allowance for Credit Losses (ACL)
Allowance for Credit Losses (ACL)	Note 6—Allowance for Credit Losses (ACL) See Note 1 — ​ The following table presents a disaggregated analysis of activity in the allowance for credit losses as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Residential ​ Residential ​ ​ ​ Residential ​ Other ​ ​ ​ ​ ​ ​ ​ CRE Owner ​ Non Owner ​ ​ ​ ​ ​ (Dollars in thousands) ​ Mortgage Sr. ​ Mortgage Jr. ​ HELOC ​ Construction ​ C&D ​ Consumer ​ Multifamily ​ Municipal ​ Occupied ​ Occupied CRE ​ C & I (2) ​ Total Year Ended December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for credit losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period January 1, 2020 ​ $ 6,128 ​ $ 15 ​ $ 4,327 ​ $ 815 ​ $ 6,211 ​ $ 4,350 ​ $ 1,557 ​ $ 956 ​ $ 10,879 ​ $ 15,219 ​ $ 6,470 ​ $ 56,927 Impact of Adoption ​ ​ 5,455 ​ ​ 11 ​ ​ 3,849 ​ ​ 779 ​ ​ 5,588 ​ ​ 3,490 ​ ​ 1,391 ​ ​ 914 ​ ​ 9,505 ​ ​ 13,898 ​ ​ 6,150 ​ ​ 51,030 Initial PCD Allowance ​ ​ 406 ​ ​ 3 ​ ​ 289 ​ ​ — ​ ​ 351 ​ ​ 669 ​ ​ 97 ​ ​ — ​ ​ 898 ​ ​ 656 ​ ​ 39 ​ ​ 3,408 Adjusted CECL balance, January 1, 2020 ​ $ 11,989 ​ $ 29 ​ $ 8,465 ​ $ 1,594 ​ $ 12,150 ​ $ 8,509 ​ $ 3,045 ​ $ 1,870 ​ $ 21,282 ​ $ 29,773 ​ $ 12,659 ​ $ 111,365 Impact of merger on provision for non-PCD loans ​ ​ 16,712 ​ ​ 226 ​ ​ 4,227 ​ ​ 4,893 ​ ​ 7,673 ​ ​ 3,836 ​ ​ 1,212 ​ ​ 919 ​ ​ 25,393 ​ ​ 35,067 ​ ​ 9,284 ​ ​ 109,442 Initial PCD Allowance ​ ​ 29,935 ​ ​ 804 ​ ​ 5,119 ​ ​ 1,302 ​ ​ 6,035 ​ ​ 6,120 ​ ​ 902 ​ ​ 1,003 ​ ​ 34,077 ​ ​ 45,787 ​ ​ 18,320 ​ ​ 149,404 Charge-offs ​ (528) ​ (24) ​ (1,053) ​ (32) ​ (347) ​ (6,158) ​ — ​ — ​ (1,205) ​ ​ (601) ​ ​ (4,654) ​ (14,602) Recoveries ​ 1,143 ​ 455 ​ 1,251 ​ 111 ​ 1,407 ​ 1,922 ​ 71 ​ — ​ 1,089 ​ ​ 518 ​ ​ 3,810 ​ 11,777 Net charge offs ​ ​ 615 ​ ​ 431 ​ ​ 198 ​ ​ 79 ​ ​ 1,060 ​ ​ (4,236) ​ ​ 71 ​ ​ — ​ ​ (116) ​ ​ (83) ​ ​ (844) ​ ​ (2,825) Provision (benefit) (1) ​ 4,310 ​ (252) ​ (1,311) ​ (2,954) ​ 40,279 ​ 12,333 ​ 2,657 ​ (2,282) ​ 16,468 ​ ​ 13,877 ​ ​ 6,798 ​ 89,923 Balance at end of period December 31, 2020 ​ $ 63,561 ​ $ 1,238 ​ $ 16,698 ​ $ 4,914 ​ $ 67,197 ​ $ 26,562 ​ $ 7,887 ​ $ 1,510 ​ $ 97,104 ​ $ 124,421 ​ $ 46,217 ​ $ 457,309 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ -1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for credit losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quantitative allowance ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collectively evaluated ​ $ 54,656 ​ $ 1,238 ​ $ 14,625 ​ $ 4,733 ​ $ 67,188 ​ $ 18,435 ​ $ 7,887 ​ $ 685 ​ $ 91,106 ​ $ 116,571 ​ $ 38,805 ​ $ 415,929 Individually evaluated ​ ​ 82 ​ ​ — ​ ​ 77 ​ ​ — ​ ​ 9 ​ ​ 120 ​ ​ — ​ ​ — ​ ​ 948 ​ ​ 6 ​ ​ 7 ​ ​ 1,249 Total quantitative allowance ​ ​ 54,738 ​ ​ 1,238 ​ ​ 14,702 ​ ​ 4,733 ​ ​ 67,197 ​ ​ 18,555 ​ ​ 7,887 ​ ​ 685 ​ ​ 92,054 ​ ​ 116,577 ​ ​ 38,812 ​ ​ 417,178 Qualitative allowance ​ ​ 8,823 ​ ​ — ​ ​ 1,996 ​ ​ 181 ​ ​ — ​ ​ 8,007 ​ ​ — ​ ​ 825 ​ ​ 5,050 ​ ​ 7,844 ​ ​ 7,405 ​ ​ 40,131 Balance at end of period December 31, 2020 ​ $ 63,561 ​ $ 1,238 ​ $ 16,698 ​ $ 4,914 ​ $ 67,197 ​ $ 26,562 ​ $ 7,887 ​ $ 1,510 ​ $ 97,104 ​ $ 124,421 ​ $ 46,217 ​ $ 457,309 ​ (1) – Additional provision for credit losses of $43.4 million was recorded during 2020 for the allowance for credit losses for unfunded commitments that is not considered in the above table. Of this amount, $9.6 million was from the initial impact from the merger with CSFL. (2) – The ACL for the C&I segment does not include reserve for PPP loans, which are government guaranteed. ​ ​ An aggregated analysis of the changes in allowance for loan losses, for comparative periods, prior to the adoption of ASU 2016-13 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-acquired Acquired Acquired Credit ​ ​ (Dollars in thousands) ​ Loans ​ Impaired Loans ​ Impaired Loans ​ Total Year Ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 51,194 ​ $ — ​ $ 4,604 ​ $ 55,798 Loans charged-off ​ (6,917) ​ ​ (2,858) ​ — ​ (9,775) Recoveries of loans previously charged off ​ 3,367 ​ ​ 547 ​ — ​ 3,914 Net charge-offs ​ (3,550) ​ ​ (2,311) ​ — ​ (5,861) Provision for loan losses charged to operations ​ 9,283 ​ ​ 2,311 ​ 1,183 ​ 12,777 Reduction due to loan removals ​ — ​ ​ — ​ (723) ​ (723) Balance at end of period ​ $ 56,927 ​ $ — ​ $ 5,064 ​ $ 61,991 Year Ended December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 43,448 ​ $ — ​ $ 4,627 ​ $ 48,075 Loans charged-off ​ (6,012) ​ ​ (2,214) ​ — ​ (8,226) Recoveries of loans previously charged off ​ 2,995 ​ ​ 305 ​ — ​ 3,300 Net charge-offs ​ (3,017) ​ ​ (1,909) ​ — ​ (4,926) Provision for loan losses charged to operations ​ 10,763 ​ ​ 1,909 ​ 1,111 ​ 13,783 Reduction due to loan removals ​ — ​ ​ — ​ (1,134) ​ (1,134) Balance at end of period ​ $ 51,194 ​ $ — ​ $ 4,604 ​ $ 55,798 ​ The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 Year Ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 5,682 ​ $ 8,754 ​ $ 9,369 ​ $ 11,913 ​ $ 3,434 ​ $ 7,454 ​ $ 1,446 ​ $ 3,101 ​ $ 41 ​ $ 51,194 ​ Charge-offs ​ (78) ​ (3) ​ (87) ​ (50) ​ (203) ​ (622) ​ (31) ​ (5,843) ​ — ​ (6,917) ​ Recoveries ​ 1,016 ​ 76 ​ 174 ​ 213 ​ 265 ​ 351 ​ 94 ​ 1,178 ​ — ​ 3,367 ​ Provision (benefit) ​ (516) ​ 1,872 ​ 1,125 ​ 520 ​ (308) ​ 1,156 ​ (173) ​ 5,511 ​ 96 ​ 9,283 ​ Balance at end of period ​ $ 6,104 ​ $ 10,699 ​ $ 10,581 ​ $ 12,596 ​ $ 3,188 ​ $ 8,339 ​ $ 1,336 ​ $ 3,947 ​ $ 137 ​ $ 56,927 ​ Loans individually evaluated for impairment ​ $ 617 ​ $ — ​ $ 24 ​ $ 102 ​ $ 132 ​ $ 366 ​ $ 50 ​ $ 55 ​ $ — ​ $ 1,346 ​ Loans collectively evaluated for impairment ​ $ 5,487 ​ $ 10,699 ​ $ 10,557 ​ $ 12,494 ​ $ 3,056 ​ $ 7,973 ​ $ 1,286 ​ $ 3,892 ​ $ 137 ​ $ 55,581 ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ 35,201 ​ $ 379 ​ $ 6,575 ​ $ 5,141 ​ $ 2,461 ​ $ 6,578 ​ $ 2,024 ​ $ 173 ​ $ — ​ $ 58,532 ​ Loans collectively evaluated for impairment ​ 933,159 ​ 1,810,759 ​ 1,777,442 ​ 2,113,698 ​ 516,167 ​ 1,274,281 ​ 216,593 ​ 538,308 ​ 13,892 ​ 9,194,299 ​ Total non-acquired loans ​ $ 968,360 ​ $ 1,811,138 ​ $ 1,784,017 ​ $ 2,118,839 ​ $ 518,628 ​ $ 1,280,859 ​ $ 218,617 ​ $ 538,481 ​ $ 13,892 ​ $ 9,252,831 ​ Year Ended December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 5,921 ​ $ 6,525 ​ $ 8,128 ​ $ 9,668 ​ $ 3,250 ​ $ 5,488 ​ $ 1,375 ​ $ 2,788 ​ $ 305 ​ $ 43,448 ​ Charge-offs ​ (76) ​ — ​ (659) ​ (80) ​ (215) ​ (500) ​ (2) ​ (4,480) ​ — ​ (6,012) ​ Recoveries ​ 1,340 ​ 11 ​ 145 ​ 132 ​ 279 ​ 256 ​ 21 ​ 811 ​ — ​ 2,995 ​ Provision (benefit) ​ (1,503) ​ 2,218 ​ 1,755 ​ 2,193 ​ 120 ​ 2,210 ​ 52 ​ 3,982 ​ (264) ​ 10,763 ​ Balance at end of period ​ $ 5,682 ​ $ 8,754 ​ $ 9,369 ​ $ 11,913 ​ $ 3,434 ​ $ 7,454 ​ $ 1,446 ​ $ 3,101 ​ $ 41 ​ $ 51,194 ​ Loans individually evaluated for impairment ​ $ 788 ​ $ 70 ​ $ 27 ​ $ 41 ​ $ 142 ​ $ 416 ​ $ 142 ​ $ 2 ​ $ — ​ $ 1,628 ​ Loans collectively evaluated for impairment ​ $ 4,894 ​ $ 8,684 ​ $ 9,342 ​ $ 11,872 ​ $ 3,292 ​ $ 7,038 ​ $ 1,304 ​ $ 3,099 ​ $ 41 ​ $ 49,566 ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ 37,913 ​ $ 1,025 ​ $ 4,142 ​ $ 6,761 ​ $ 2,826 ​ $ 1,291 ​ $ 2,872 ​ $ 188 ​ $ — ​ $ 57,018 ​ Loans collectively evaluated for impairment ​ 803,532 ​ 1,414,526 ​ 1,513,409 ​ 1,929,504 ​ 492,322 ​ 1,053,661 ​ 211,481 ​ 448,476 ​ 9,357 ​ 7,876,268 ​ Total non-acquired loans ​ $ 841,445 ​ $ 1,415,551 ​ $ 1,517,551 ​ $ 1,936,265 ​ $ 495,148 ​ $ 1,054,952 ​ $ 214,353 ​ $ 448,664 ​ $ 9,357 ​ $ 7,933,286 ​ ​ ​ The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for acquired non-credit impaired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 Year Ended December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Charge-offs ​ (44) ​ — ​ (786) ​ (6) ​ (263) ​ (1,289) ​ (26) ​ (444) ​ (2,858) ​ Recoveries ​ 3 ​ — ​ — ​ 26 ​ 206 ​ 190 ​ 71 ​ 51 ​ 547 ​ Provision (benefit) ​ 41 ​ — ​ 786 ​ (20) ​ 57 ​ 1,099 ​ (45) ​ 393 ​ 2,311 ​ Balance, December 31, 2019 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 33,569 ​ 447,441 ​ 307,193 ​ 496,431 ​ 188,732 ​ 101,880 ​ 95,697 ​ 89,484 ​ 1,760,427 ​ Total acquired non-credit impaired loans ​ $ 33,569 ​ $ 447,441 ​ $ 307,193 ​ $ 496,431 ​ $ 188,732 ​ $ 101,880 ​ $ 95,697 ​ $ 89,484 ​ $ 1,760,427 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2018 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Charge-offs ​ (107) ​ — ​ (28) ​ (70) ​ (436) ​ (1,108) ​ — ​ (465) ​ (2,214) ​ Recoveries ​ 8 ​ — ​ — ​ 64 ​ 102 ​ 63 ​ — ​ 68 ​ 305 ​ Provision (benefit) ​ 99 ​ — ​ 28 ​ 6 ​ 334 ​ 1,045 ​ — ​ 397 ​ 1,909 ​ Balance, December 31, 2019 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 165,070 ​ 679,253 ​ 421,841 ​ 628,813 ​ 242,425 ​ 212,537 ​ 133,110 ​ 111,777 ​ 2,594,826 ​ Total acquired non-credit impaired loans ​ $ 165,070 ​ $ 679,253 ​ $ 421,841 ​ $ 628,813 ​ $ 242,425 ​ $ 212,537 ​ $ 133,110 ​ $ 111,777 ​ $ 2,594,826 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for acquired credit impaired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Estate- ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ Construction and ​ Residential ​ ​ ​ ​ Commercial ​ ​ ​ (Dollars in thousands) ​ Real Estate ​ Development ​ Real Estate ​ Consumer ​ and Industrial ​ Total Year Ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, December 31, 2018 ​ $ 801 ​ $ 717 ​ $ 2,246 ​ $ 761 ​ $ 79 ​ $ 4,604 ​ Provision for loan losses ​ 577 ​ (148) ​ 716 ​ (222) ​ 260 ​ 1,183 ​ Reduction due to loan removals ​ (1) ​ — ​ (407) ​ — ​ (315) ​ (723) ​ Balance, December 31, 2019 ​ $ 1,377 ​ $ 569 ​ $ 2,555 ​ $ 539 ​ $ 24 ​ $ 5,064 ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ 1,377 ​ $ 569 ​ $ 2,555 ​ $ 539 ​ $ 24 ​ $ 5,064 ​ Loans:* ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 130,938 ​ 25,032 ​ 163,359 ​ 35,488 ​ 7,029 ​ 361,846 ​ Total acquired credit impaired loans ​ $ 130,938 ​ $ 25,032 ​ $ 163,359 ​ $ 35,488 ​ $ 7,029 ​ $ 361,846 ​ Year Ended December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, December 31, 2017 ​ $ 288 ​ $ 180 ​ $ 3,553 ​ $ 461 ​ $ 145 ​ $ 4,627 ​ Provision for loan losses ​ 532 ​ 657 ​ (892) ​ 303 ​ 511 ​ 1,111 ​ Reduction due to loan removals ​ (19) ​ (120) ​ (415) ​ (3) ​ (577) ​ (1,134) ​ Balance, December 31, 2018 ​ $ 801 ​ $ 717 ​ $ 2,246 ​ $ 761 ​ $ 79 ​ $ 4,604 ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ 801 ​ $ 717 ​ $ 2,246 ​ $ 761 ​ $ 79 ​ $ 4,604 ​ Loans:* ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 196,764 ​ 32,942 ​ 207,482 ​ 42,492 ​ 10,043 ​ 489,723 ​ Total acquired credit impaired loans ​ $ 196,764 ​ $ 32,942 ​ $ 207,482 ​ $ 42,492 ​ $ 10,043 ​ $ 489,723 ​ * 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.

Other Real Estate Owned and Ban

Other Real Estate Owned and Bank Premises Held for Sale	12 Months Ended
	Dec. 31, 2020
Other Real Estate Owned and Bank Premises Held for Sale
Other Real Estate Owned and Bank Premises Held for Sale	Note 7—Other Real Estate Owned and Bank Premises Held for Sale The following is a summary of the changes in the carrying value of OREO and Bank Premises Held for Sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ OREO and Bank Premises ​ Balance, December 31, 2017 ​ $ 11,203 ​ Acquired in Park Sterling Corp. acquisition ​ 210 ​ Additions, net ​ 13,391 ​ Writedowns ​ (1,420) ​ Sold ​ (11,974) ​ Balance, December 31, 2018 ​ 11,410 ​ Other Real Estate Owned at December 31, 2018 ​ ​ 6,153 ​ Bank Premises Held for Sale at December 31, 2018 ​ ​ 5,257 ​ Additions, net ​ ​ 10,373 ​ Writedowns ​ ​ (1,192) ​ Sold ​ ​ (8,627) ​ Balance, December 31, 2019 ​ ​ 11,964 ​ Other Real Estate Owned at December 31, 2019 ​ ​ 6,539 ​ Bank Premises Held for Sale at December 31, 2019 ​ ​ 5,425 ​ Acquired in the CSFL acquisition ​ ​ 28,311 ​ Additions, net ​ ​ 27,340 ​ Writedowns ​ ​ (1,085) ​ Sold ​ ​ (18,610) ​ Balance, December 31, 2020 ​ ​ 47,920 ​ Other Real Estate Owned at December 31, 2020 ​ ​ 11,914 ​ Bank Premises Held for Sale at December 31, 2020 ​ $ 36,006 ​ ​ At December 31, 2020, there were a total of 42 properties included in OREO which compares to 47 properties included in OREO, at December 31, 2019. At December 31, 2020, there were a total of 33 properties included in bank premises held for sale which compares to 12 properties included in premises held for sale, at December 31, 2019. During the second quarter of 2020, a reclassification was made so that bank property held for sale is now separately disclosed on the balance sheet. At December 31, 2020, the Company had $804,000 in residential real estate included in OREO and $5.0 million in residential real estate consumer mortgage loans in the process of foreclosure.

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2020
Premises and Equipment
Premises and Equipment	Note 8—Premises and Equipment Premises and equipment consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ Useful Life ​ 2020 ​ 2019 Land ​ ​ ​ $ 152,263 $ 74,913 ​ Buildings and leasehold improvements 15 - 40 years ​ 406,078 ​ 226,750 ​ Equipment and furnishings 3 - 10 years ​ 161,009 ​ ​ 106,696 ​ Lease right of use assets ​ ​ ​ ​ ​ ​ ​ 113,422 ​ ​ 87,389 ​ Construction in process ​ ​ ​ ​ ​ ​ 3,618 ​ 1,977 ​ Total ​ ​ ​ ​ ​ ​ 836,390 ​ 497,725 ​ Less accumulated depreciation ​ ​ ​ ​ ​ ​ (257,151) ​ (180,404) ​ ​ ​ ​ ​ ​ ​ ​ $ 579,239 ​ $ 317,321 ​ ​ Depreciation expense charged to operations was $25.3 million, $18.2 million, and $18.7 million for the years ended December 31, 2020, 2019, and 2018, respectively. The overall increase in premises and equipment and depreciation from prior year was due the merger with CSFL in June 2020 when $330.3 million in premises and equipment was acquired. At December 31, 2020 and 2019, computer software with an original cost of $37.4 million and $13.7 million, respectively, were being amortized using the straight-line method over thirty-six months. Amortization expense totaled $2.4 million, $1.2 million, and $2.1 million for the years ended December 31, 2020, 2019, and 2018, respectively. There were Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. was related to a new public website. These costs are being held in a suspense account classified as other assets on the balance sheet until the project is complete when they will then begin to be depreciated. See Note 22 —

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Other Intangible Assets
Goodwill and Other Intangible Assets	Note 9—Goodwill and Other Intangible Assets The Company evaluated the carrying value of goodwill as of April 30, 2020, its annual test date, and obtained a third-party valuation during the fourth quarter of 2020 and concluded that no impairment charge was necessary. The Company will continue to monitor the impact of COVID-19 on the Company’ business, operating results, cash flows and/or financial condition. The following is a summary of changes in the carrying amounts of goodwill: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Balance at beginning of period $ 1,002,900 $ 1,002,900 ​ Additions: ​ ​ ​ ​ ​ ​ ​ Goodwill from CenterState acquisition ​ 561,042 ​ ​ — ​ Balance at end of period ​ $ 1,563,942 ​ $ 1,002,900 ​ ​ The Company’s other intangible assets, consisting of core deposit intangibles, noncompete intangibles, and client list intangibles are included on the face of the balance sheet. The following is a summary of gross carrying amounts and accumulated amortization of other intangible assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Gross carrying amount ​ $ 258,554 $ 119,501 ​ Accumulated amortization ​ ​ (95,962) ​ (69,685) ​ ​ ​ ​ $ 162,592 ​ $ 49,816 ​ ​ Amortization expense totaled $27.0 million and $13.1 million and $14.2 million for the years ended December 31, 2020, 2019, and 2018, respectively. Other intangibles are amortized using either the straight-line method or an accelerated basis over their estimated useful lives, with lives generally between 2 and 15 years . Estimated amortization expense for other intangibles for each of the next five years is as follows: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ Year ended December 31: ​ ​ 2021 ​ $ 33,845 ​ 2022 ​ 30,056 ​ 2023 ​ 24,634 ​ 2024 ​ 19,790 ​ 2025 ​ 16,480 ​ Thereafter ​ 37,787 ​ ​ ​ $ 162,592 ​ ​ ​ ​ ​ ​ ​

Deposits

Deposits	12 Months Ended
	Dec. 31, 2020
Deposits
Deposits	Note 10—Deposits ​ The Company’s total deposits are comprised of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Certificates of deposit ​ ​ $ 3,743,271 $ 1,651,399 ​ Interest-bearing demand deposits ​ ​ 14,539,928 ​ 5,966,496 ​ Non-interest bearing demand deposits ​ ​ 9,711,338 ​ 3,245,306 ​ Savings deposits ​ ​ 2,694,011 ​ 1,309,896 ​ Other time deposits ​ ​ 5,334 ​ 3,999 ​ Total deposits ​ ​ $ 30,693,882 ​ $ 12,177,096 ​ ​ At December 31, 2020 and 2019 the Company had $814.2 million and $303.2 million in certificates of deposits of $250,000 and greater, respectively. At December 31, 2020 the Company held $600.0 million of traditional, out-of- market brokered deposits. At December 31, 2019, there were no traditional, out-of-market brokered deposits. At December 31, 2020, the scheduled maturities of time deposits (includes $5.3 million of other time deposits) of all denominations are as follows: ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Year ended December 31: ​ ​ ​ ​ 2021 ​ $ 2,704,310 ​ 2022 ​ 610,282 ​ 2023 ​ 210,321 ​ 2024 ​ 97,640 ​ 2025 ​ 123,218 ​ Thereafter ​ 2,834 ​ ​ ​ $ 3,748,605 ​ ​

Federal Funds Purchased and Sec

Federal Funds Purchased and Securities Sold Under Agreements to Repurchase	12 Months Ended
	Dec. 31, 2020
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase	Note 11—Federal Funds Purchased and Securities Sold Under Agreements to Repurchase Federal funds purchased and securities sold under agreements to repurchase generally mature within one per our policies. Certain of the borrowings have no defined maturity date. Information concerning federal funds purchased and securities sold under agreements to repurchase are below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2020 ​ 2019 ​ 2018 (Dollars in thousands) ​ Amount ​ Rate ​ Amount ​ Rate ​ Amount ​ Rate At period-end: ​ ​ ​ ​ Federal funds purchased and securities sold under repurchase agreements ​ $ 779,666 0.17 % $ 298,741 0.90 % $ 270,649 1.08 % Average for the year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal funds purchased and securities sold under repurchase agreements ​ $ 553,110 0.35 % $ 282,172 0.93 % $ 312,768 0.75 % Maximum month-end balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal funds purchased and securities sold under repurchase agreements ​ $ 779,666 ​ ​ ​ $ 321,833 ​ ​ ​ $ 362,047 ​ ​ ​ ​ Securities Sold Under Agreements to Repurchase ​ Securities sold under agreements to repurchase (“repurchase agreements”) represent funds received from customers, generally on an overnight or continuous basis, which are collateralized by investment securities owned or, at times, borrowed and re-hypothecated by the Company. Repurchase agreements are subject to terms and conditions of the master repurchase agreements between the Company and the client and are accounted for as secured borrowings. The Company monitors the fair value of the underlying securities on a daily basis. Some securities underlying these agreements include arrangements to resell securities from broker- dealers approved by the Company. Repurchase agreements are reflected at the amount of cash received in connection with the transaction and included in federal funds purchased and securities sold under agreements to repurchase on the consolidated balance sheets. ​ At December 31, 2020 and December 31, 2019, the Company’s repurchase agreements totaled $394.9 million and $242.2 million, respectively. All of the Company’s repurchase agreements were overnight or continuous (until-further-notice) agreements at December 31, 2020 and December 31, 2019. These borrowings were collateralized with government, government-sponsored enterprise, or state and political subdivision-issued securities with a carrying value of 31, 2019, respectively. Declines in the value of the collateral would require the Company to increase the amounts of securities pledged.

Other Borrowings

Other Borrowings	12 Months Ended
	Dec. 31, 2020
Other Borrowings.
Other Borrowings	Note 12—Other Borrowings ​ The Company’s other borrowings were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2020 ​ ​ ​ 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ Interest ​ ​ ​ ​ ​ ​ Average ​ Interest ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Rate at ​ ​ ​ Average ​ Interest ​ Rate at ​ ​ ​ Average ​ Interest ​ (Dollars in thousands) Maturity 12/31/2020 Balance ​ Balance Rate 12/31/2019 Balance ​ Balance Rate ​ Short-term borrowings: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal Home Loan Bank Fixed Rate Credit ​ 3/4/2020 ​ — % $ — ​ ​ ​ ​ ​ ​ 1.75 % $ 200,000 ​ ​ ​ ​ ​ ​ Federal Home Loan Bank Fixed Rate Credit ​ 3/19/2020 ​ — % ​ — ​ ​ ​ ​ ​ ​ 1.73 % ​ 350,000 ​ ​ ​ ​ ​ ​ Federal Home Loan Bank Fixed Rate Credit ​ 3/30/2020 ​ — % — ​ ​ ​ ​ ​ ​ 1.72 % 150,000 ​ ​ ​ ​ ​ ​ Total short-term borrowings ​ ​ ​ — % ​ — ​ $ 745,939 ​ 0.63 % 1.73 % ​ 700,000 ​ $ 538,627 ​ 2.35 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-term borrowings ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ SCBT Capital Trust I junior subordinated debt (1) ​ 6/15/2035 ​ 2.01 % 12,372 ​ ​ ​ ​ ​ ​ 3.68 % 12,372 ​ ​ ​ ​ ​ ​ SCBT Capital Trust II junior subordinated debt (1) ​ 6/15/2035 ​ 2.01 % 8,248 ​ ​ ​ ​ ​ ​ 3.68 % 8,248 ​ ​ ​ ​ ​ ​ SCBT Capital Trust III junior subordinated debt (1) ​ 7/18/2035 ​ 1.81 % ​ 20,619 ​ ​ ​ ​ ​ ​ 3.48 % ​ 20,619 ​ ​ ​ ​ ​ ​ SAVB Capital Trust I junior subordinated debt (1) ​ 10/7/2033 ​ 3.09 % 6,186 ​ ​ ​ ​ ​ ​ 4.84 % 6,186 ​ ​ ​ ​ ​ ​ SAVB Capital Trust II junior subordinated debt (1) ​ 12/15/2034 ​ 2.42 % 4,124 ​ ​ ​ ​ ​ ​ 4.09 % 4,124 ​ ​ ​ ​ ​ ​ TSB Statutory Trust I junior subordinated debt (1) ​ 3/14/2037 ​ 1.94 % 3,093 ​ ​ ​ ​ ​ ​ 3.61 % 3,093 ​ ​ ​ ​ ​ ​ Southeastern Bank Financial Statutory Trust I junior subordinated debt (1) ​ 12/15/2035 ​ 1.62 % 10,310 ​ ​ ​ ​ ​ ​ 3.29 % 10,310 ​ ​ ​ ​ ​ ​ Southeastern Bank Financial Statutory Trust II junior subordinated debt (1) ​ 6/15/2036 ​ 1.62 % 10,310 ​ ​ ​ ​ ​ ​ 3.29 % 10,310 ​ ​ ​ ​ ​ ​ CSBC Statutory Trust I junior subordinated debt (1) ​ 12/15/2035 ​ 1.79 % 15,464 ​ ​ ​ ​ ​ ​ 3.46 % 15,464 ​ ​ ​ ​ ​ ​ Community Capital Statutory Trust I junior subordinated debt (1) ​ 6/15/2036 ​ 1.77 % 10,310 ​ ​ ​ ​ ​ ​ 3.44 % 10,310 ​ ​ ​ ​ ​ ​ FCRV Statutory Trust I junior subordinated debt (1) ​ 12/15/2036 ​ 1.92 % 5,155 ​ ​ ​ ​ ​ ​ 3.59 % 5,155 ​ ​ ​ ​ ​ ​ Provident Community Bancshares Capital Trust I junior subordinated debt (1) ​ 3/1/2037 ​ 1.97 % 4,124 ​ ​ ​ ​ ​ ​ 3.84 % 4,124 ​ ​ ​ ​ ​ ​ Provident Community Bancshares Capital Trust II junior subordinated debt (1) ​ 10/1/2036 ​ 1.97 % 8,248 ​ ​ ​ ​ ​ ​ 3.65 % 8,248 ​ ​ ​ ​ ​ ​ CenterState Banks of Florida Statutory Trust I junior subordinated debt (1) ​ 9/22/2033 ​ 3.30 % ​ 10,310 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Valrico Capital Statutory Trust junior subordinated debt (1) ​ 9/8/2034 ​ 2.93 % ​ 2,577 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Federal Trust Statutory Trust I junior subordinated debt (1) ​ 9/17/2033 ​ 3.18 % ​ 5,155 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Gulfstream Bancshares Capital Trust II junior subordinated debt (1) ​ 3/6/2037 ​ 1.93 % ​ 3,093 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Homestead Statutory Trust I junior subordinated debt (1) ​ 10/1/2036 ​ 1.88 % ​ 10,495 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ BSA Financial Statutory Trust I junior subordinated debt (1) ​ 12/15/2035 ​ 1.77 % ​ 5,155 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ MRCB Statutory Trust II junior subordinated debt (1) ​ 9/15/2036 ​ 1.82 % ​ 3,093 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Fair Market Value Discount Trust Preferred Debt Acquired ​ ​ ​ ​ ​ ​ (14,116) ​ ​ ​ ​ ​ ​ ​ ​ ​ (2,730) ​ ​ ​ ​ ​ ​ Total Junior Subordinated Debt ​ ​ ​ 2.05 % ​ 144,325 ​ ​ 131,817 ​ 2.51 % 3.60 % ​ 115,833 ​ ​ 115,490 ​ 4.20 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Residential Warranty Corp. subordinated note (5) ​ 4/15/2021 ​ 5.00 % ​ 7,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Messiah College subordinated note (5) ​ 4/15/2021 ​ 5.00 % ​ 4,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ National Bank of Commerce subordinated debt (2) ​ 6/1/2026 ​ 6.00 % ​ 25,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Landmark Bancshares subordinated debt (3) ​ 6/30/2027 ​ 6.50 % ​ 13,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ CenterState Bank Corporation subordinated debt (4) ​ 6/1/2030 ​ 5.75 % ​ 200,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Long-term subordinated debt costs ​ ​ ​ ​ ​ ​ (3,146) ​ ​ ​ ​ ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ ​ Total Subordinated Debt ​ ​ ​ 5.78 % ​ 245,854 ​ ​ 139,584 ​ 5.69 % — % ​ — ​ ​ — ​ — % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other Long Term Debt ​ Various ​ — % ​ — ​ ​ 92 ​ 0.50 % 0.50 % 103 ​ ​ 636 ​ 6.02 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term borrowings ​ ​ ​ 4.40 % ​ 390,179 ​ ​ 271,493 ​ 3.60 % 3.60 % ​ 115,936 ​ ​ 116,126 ​ 3.60 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total borrowings ​ ​ ​ 4.40 % $ 390,179 ​ $ 1,017,432 ​ 1.58 % 2.00 % $ 815,936 ​ $ 654,753 ​ 2.57 % ​ (1) All of the junior subordinated debt above is adjustable rate based on three-month LIBOR plus a spread ranging from (2) The Notes bear interest at a fixed rate of per year, from, and including, May 19, 2016, to, but excluding, June 1, 2021. On June 1, 2021, the Notes convert to a floating rate equal to three-month LIBOR plus bps. The Notes may be redeemed by the Company after June 1, 2021. (3) The Notes bear interest at a fixed rate of per year, to, but excluding, June 30, 2022. On June 30, 2022, the Notes convert to a floating rate equal to three-month LIBOR plus bps. The Notes may be redeemed by the Company after June 30, 2022. (4) The per year, to, but excluding, June 1, 2025. On June 1, 2025, the Notes convert to a floating rate equal to SOFR plus bps. The Notes may be redeemed by the Company after June 1, 2025. The carrying balance of this debt is (5) These subordinated notes are not classified as Tier 2 Capital for regulatory capital purposes. Short-Term Borrowings ​ The Company has from time-to- time entered into borrowing agreements with the FHLB and FRB. Borrowings under these agreements are collateralized by stock in the FHLB, qualifying first and second mortgage residential loans, investment securities, and commercial real estate loans under a blanket-floating lien. ​ As of December 31, 2020, there were no outstanding Short-Term borrowings. At December 31, 2019, there was $700.0 million in outstanding Short-Term FHLB advances. For the years ended December 31, 2020 and 2019, the average balance for short-term borrowings was $745.9 million and $538.6 million, respectively. There were no short-term borrowings at December 31, 2020, but the year-to-date weighted average cost for the year ended December 31, 2020 was 0.63 %. The weighted average cost of the short-term borrowing at period end December 31, 2019 was 1.73% and the weighted average cost year to date for the year ended December 31, 2019 was 2.35 %. Net eligible loans of the Company pledged via a blanket lien to the FHLB for advances and letters of credit at December 31, 2020, were approximately $3.6 billion and investment securities pledged were approximately $346.6 million. This allows the Company a total borrowing capacity at the FHLB of approximately $2.8 billion. After accounting for letters of credit totaling 31, 2020. The Company also has a total borrowing capacity at the FRB of $1.2 billion at December 31, 2020 secured by a blanket lien on $2.0 billion in net eligible loans of the Company. The Company had no outstanding borrowings with the FRB at December 31, 2020. ​ During the fourth quarter of 2020, we paid-off early our FHLB advances of $700.0 million and terminated the interest rate swaps related to these advances at a cost of $38.8 million reflected in noninterest expense in the Consolidated Statements of Income. ​ Junior Subordinated Debt ​ The obligations of the Company with respect to the issuance of the capital securities constitute a full and unconditional guarantee by the Company of the trusts’ obligations with respect to the capital securities. Subject to certain exceptions and limitations, the Company may elect from time to time to defer interest payments on the junior subordinated debt securities, which would result in a deferral of distribution payments on the related capital securities. ​ All of the Company’s junior subordinated debt is callable after five years from issuance. Therefore, all of the junior subordinated debt is callable at December 31, 2020. ​ As of December 31, 2020, the sole assets of the trusts were an aggregate of $144.3 million of the Company’s junior subordinated debt securities with like maturities and like interest rates to the trust preferred securities. ​ As of December 31, 2020, the Company recorded a $144.3 million liability for the junior subordinated debt securities, net of a $14.1 million discount recorded on Southeastern Bank Financial Statutory Trust I and II, Citizens South Banking Corporation Statutory Trust I, Community Capital Statutory Trust I, FCRV Statutory Trust I, Provident Community Bancshares Capital Trust I and II, CenterState Banks of Florida Statutory Trust I, Federal Trust Statutory Trust I, Gulfstream Bancshares Capital Trust II, Homestead Statutory Trust I, BSA Financial Statutory Trust I, and MRCB Statutory Trust II. The Company, as issuer, can call any of these subordinated debt securities without penalty. If the Company were to call the securities, the amount paid to the holders would be $158.4 million and the Company would fully amortize any remaining discount into interest expense. The remaining discount is being amortized over either a one and one-half year period, a five-year period or a fourteen and one-half year period depending on the merger acquired. ​ As of December 31, 2020, and 2019, there was $144.3 million (net of discount of $14.1 million) and $115.8 million (net of discount of $2.7 million), respectively, in junior subordinated debt. The weighted average cost of the junior subordinated debt at period end December 31, 2020 was 2.05% and the weighted average cost year to date for the year ended December 31, 2020 of 2.51 %. This does not take into account the discount. If the discount were taken into account, the weighted average cost year to date would be 3.56 %. This compares to a weighted average cost of the junior subordinated debt at period end December 31, 2019 of 3.60% and the weighted average cost year to date for the year ended December 31, 2019 of 4.20 %. If the discount were taken into account, the weighted average cost year to date would be 4.88% in 2019. ​ Pursuant to the Basel III rules adopted by the bank regulatory agencies in July 2013, financial institutions with less than $15 billion in total assets may continue to include their trust preferred securities issued prior to May 19, 2010 in Tier 1 capital, but cannot include in Tier 1 capital any trust preferred securities issued after such date. A financial institution may continue to include its trust preferred securities in Tier 1 capital if it exceeds $15 billion in total assets through organic growth, but if it exceeds $15 billion in total assets through an acquisition or enters into an acquisition after exceeding $15 billion in total assets through organic growth, then the trust preferred securities would no longer be included in Tier 1 capital. Therefore, upon closing on the merger with CSFL in 2020, total trust preferred securities of $158.4 million of the combined Company would no longer be included in Tier 1 capital. Following the merger, these trust preferred securities are now only included in Tier 2 capital for regulatory capital purposes. ​ Subordinated Debt and Notes ​ As of December 31, 2020, the Company recorded a $245.9 million liability for the subordinated debt, which was net of $3.1 million in debt issuance costs recorded on the CenterState subordinated debt issuance of $200.0 million. The remaining balance of the debt issuance costs are being amortized over an eight and one-half year period. There was no subordinated debt outstanding at December 31, 2019 as all this debt was acquired in the merger with CSFL in June 2020. ​ The weighted average cost of the subordinated debt at period end December 31, 2020 was 5.78% and the weighted average cost year to date for the year ended December 31, 2020 of 5.69 %. This does not take into account the amortization of the debt issuance costs. If the debt issuance costs were taken into account, the weighted average cost year to date would be 5.93 %. ​ Qualifying subordinated debt can be included in Tier 2 capital for regulatory capital purposes. Of our subordinated debt, the amounts for the National Bank of Commerce, Landmark Bancshares and CenterState Bank Corporation totaling $238.0 million qualify for Tier 2 capital. The subordinated notes for Residential Warranty Corp. and Messiah College totaling $11.0 million do not qualify for Tier 2 capital purposes. ​ Line of Credit ​ On November 15, 2020, the Company entered into an amendment to its Credit Agreement (the “Agreement”) with U.S. Bank National Association (the “Lender”). The Agreement provides for a $100 million unsecured line of credit by the Lender to the Company. The maturity date of the Agreement is November 15, 2021, provided that the Agreement may be extended subject to the approval of the Lender. Borrowings by the Company under the Agreement will bear interest at a rate per annum equal to 2.00% plus the greater of 0.00% or one-month LIBOR. As of December 31, 2020 and 2019, and there was ​ Principal maturities of other borrowings are summarized below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Junior ​ ​ ​ ​ ​ Subordinated ​ FHLB ​ Subordinated ​ ​ (Dollars in thousands) Debt ​ Advances ​ Debt ​ Total Year Ended December 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 $ — ​ $ — ​ $ 11,000 ​ $ 11,000 ​ 2022 — ​ — ​ — ​ — ​ 2023 — ​ — ​ — ​ — ​ 2024 — ​ — ​ — ​ — ​ 2025 — ​ — ​ — ​ — ​ Thereafter 144,325 ​ — ​ 234,854 ​ 379,179 ​ ​ $ 144,325 ​ $ — ​ $ 245,854 ​ $ 390,179 ​ ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Taxes
Income Taxes	Note 13—Income Taxes The provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Current: ​ ​ ​ ​ Federal ​ $ 16,245 ​ $ 40,375 ​ $ 25,275 ​ State ​ 13,296 ​ 4,965 ​ 6,783 ​ Total current tax expense ​ 29,541 ​ 45,340 ​ 32,058 ​ Deferred: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ (36,801) ​ (1,598) ​ 12,557 ​ State ​ (9,400) ​ 200 ​ 769 ​ Total deferred tax (benefit) expense ​ (46,201) ​ (1,398) ​ 13,326 ​ (Benefit) provision for income taxes ​ $ (16,660) ​ $ 43,942 ​ $ 45,384 ​ ​ The provision for income taxes differs from that computed by applying the federal statutory income tax rate of 21% in 2020, 2019 and 2018 to income before provision for income taxes, as indicated in the following analysis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Income taxes at federal statutory rate $ 21,834 $ 48,389 $ 47,094 ​ Increase (reduction) of taxes resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State income taxes, net of federal tax benefit ​ 3,077 ​ 4,080 ​ 5,916 ​ Non-deductible merger expenses ​ ​ 1,344 ​ ​ — ​ ​ — ​ Increase in cash surrender value of BOLI policies ​ ​ (2,389) ​ ​ (1,210) ​ ​ (1,261) ​ Tax-exempt interest ​ (2,257) ​ (1,877) ​ (2,037) ​ Income tax credits ​ (7,138) ​ (6,881) ​ (3,118) ​ Non-deductible FDIC premiums ​ ​ 1,364 ​ ​ 133 ​ ​ 191 ​ Non-deductible executive compensation ​ ​ 1,016 ​ ​ 315 ​ ​ 305 ​ Revaluation of net deferred tax asset due to tax law change ​ ​ — ​ ​ — ​ ​ (991) ​ Benefit of tax loss carryback under CARES Act ​ ​ (31,468) ​ ​ — ​ ​ — ​ Other, net ​ (2,043) ​ 993 ​ (715) ​ ​ ​ $ (16,660) ​ $ 43,942 ​ $ 45,384 ​ ​ Tax Reform Act of 2017, among other things, lowered the maximum corporate tax rate from 35% to 21 % beginning in 2018. The deferred tax assets and liabilities represent the future tax return consequences of those differences, which will either be taxable or deductible when the assets and liabilities are recovered or settled. Deferred tax assets and liabilities are reflected at income tax rates applicable to the period in which the deferred tax assets or liabilities are expected to be realized or settled. As changes in tax laws or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. As a result of the Tax Reform Act, the Company revalued its deferred tax assets and liabilities through the provision for income taxes. The SEC staff issued Staff Accounting Bulletin No. 118 in December 2017 to address the application of U.S. GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Reform Act. The Company recognized a provisional tax impact of $26.6 million as additional income tax expense related to the revaluation of deferred tax assets and liabilities and included that amount in its consolidated financial statements for the year ended December 31, 2017. In addition to that, during 2018, the Company finalized its calculation for the revaluation of deferred tax assets and liabilities and recorded that impact in its consolidated financial statements for the year ended December 31, 2018. ​ The CARES Act was passed in March, 2020 in response to the global pandemic. As a result of the legislation, tax law changed to include the ability to carry back net operating losses ("NOLs") generated in 2018 through 2020 for five years, which was previously disallowed under The Tax Reform Act. Due to differences in tax and GAAP accounting rules, which relates to a tax method change to fair value for loans, the Company filed a short period tax return as of the merger date, which generated a NOL. This loss was carried back to the 2013 through 2015 tax years at a 35% tax rate, generating one time income tax benefit of $31.5 million. The components of the net deferred tax asset are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Allowance for credit losses $ 119,602 $ 14,468 ​ Other-than-temporary impairment on securities ​ 268 ​ 250 ​ Share-based compensation ​ 2,807 ​ 4,975 ​ Pension plan and post-retirement benefits ​ 516 ​ 494 ​ Deferred compensation ​ 13,671 ​ 12,475 ​ Purchase accounting adjustments ​ 11,772 ​ 24,530 ​ Other real estate owned ​ 899 ​ 380 ​ Net operating loss and tax credit carryforwards ​ 26,229 ​ 10,347 ​ Deferred loan fees and costs ​ ​ 12,826 ​ ​ — ​ Nonaccrual Interest ​ ​ 3,141 ​ ​ — ​ Lease liability ​ ​ 28,179 ​ ​ 19,146 ​ Cash flow hedge ​ — ​ 3,034 ​ Other ​ 603 ​ 1,040 ​ Total deferred tax assets ​ 220,513 ​ 91,139 ​ Unrealized gains on investment securities available for sale ​ 13,026 ​ 2,373 ​ Depreciation ​ 18,326 ​ 6,585 ​ Intangible assets ​ 34,648 ​ 9,979 ​ Net deferred loan costs ​ — ​ 9,082 ​ Right of use assets ​ ​ 27,012 ​ ​ 19,465 ​ Prepaid expense ​ 1,950 ​ 474 ​ Tax deductible goodwill ​ 1,302 ​ 810 ​ Mortgage servicing rights ​ ​ 6,134 ​ ​ 6,688 ​ Other ​ 1,534 ​ 480 ​ Total deferred tax liabilities ​ 103,932 ​ 55,936 ​ Net deferred tax assets before valuation allowance ​ 116,581 ​ 35,203 ​ Less, valuation allowance ​ (5,635) ​ (3,887) ​ Net deferred tax assets ​ $ 110,946 ​ $ 31,316 ​ ​ The Company had federal net operating loss (“NOL”) and realized built-in loss carryforwards of $91.9 million and $31.5 million for the years ended December 31, 2020 and 2019, respectively, which expire in varying amounts between 2026 to 2036. All of the Company’s loss carryforwards are subject to Section 382 of the Internal Revenue Code, which places an annual limitation on the amount of federal net operating loss carryforwards which the Company may utilize after a change in control, and also limits the Company’s ability to utilize certain tax deductions (Realized Built-in Losses or RBIL) due to the existence of a Net Unrealized Built-in Loss (“NUBIL”) at the time of the change in control. The Company is allowed to carry forward any such limited RBIL under terms similar to those related to NOLs. The Company acquired federal net operating loss carryforwards of $62.9 million in the 2020 merger with CSFL. These acquired NOLs are subject to a combined annual Section 382 limitation of $16.0 million. In total, the combined allowable deduction for all loss carryforwards on an annual basis is $20.7 million. The Company also has acquired state net operating losses in Georgia, Florida and Alabama. These are also subject to annual limitations under Section 382, similar to the federal NOLs. The Company expects all Section 382 limited carryforwards to be realized within the applicable carryforward period. The Company has state net operating loss carryforwards of $222.9 million and $108.6 million for the years ended December 31, 2020 and 2019, respectively, most of which expire in varying amounts through 2038. There is a valuation allowance of $7.1 million that relates to the parent company’s state operating loss carryforwards for which realizability is uncertain. The change in the valuation allowance for the current year was $3.2 million and for years ended December 31, 2019 and 2018, the change was immaterial. During 2020, there were two events that impacted deferred taxes, but were not recorded through deferred tax expense (continuing operations); the impact of the adoption of CECL booked through retained earnings and recording of deferred taxes acquired as part of the CenterState merger. The combined impact of those items in 2020 was ​ In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. Based on the level of historical taxable income and projections for future taxable income over the periods in which the deferred tax assets are deductible, management believes it is more likely than not that the Company will realize the benefits of these deferred tax assets, net of the valuation allowance at December 31, 2020. ​ As of December 31, 2020 material unrecognized tax benefits or accrued interest and penalties. It is the Company’s policy to account for interest and penalties accrued relative to unrecognized tax benefits as a component of income tax expense. ​ Generally, the Company’s federal and state income tax returns are no longer subject to examination by taxing authorities for years prior to 2017.

Other Expense

Other Expense	12 Months Ended
	Dec. 31, 2020
Other Expense
Other Expense	Note 14—Other Expense ​ The following is a summary of the components of other noninterest expense: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Business development and staff related $ 8,721 $ 8,837 $ 9,536 ​ Bankcard expense ​ ​ 2,224 ​ ​ 2,331 ​ ​ 1,783 ​ Other loan expense ​ ​ 5,105 ​ ​ 2,087 ​ ​ 2,028 ​ Director and shareholder expense ​ ​ 4,175 ​ ​ 1,859 ​ ​ 2,065 ​ Armored carrier and courier expense ​ ​ 2,449 ​ ​ 1,874 ​ ​ 2,102 ​ Property and sales tax ​ 3,936 ​ 2,131 ​ 1,760 ​ Low income housing tax credit partnership amortization ​ ​ 12,977 ​ ​ 6,141 ​ ​ 3,829 ​ Donation ​ ​ 2,121 ​ ​ 999 ​ ​ 960 ​ Other ​ 11,137 ​ 5,234 ​ 5,312 ​ ​ ​ $ 52,845 ​ $ 31,493 ​ $ 29,375 ​ ​

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Common Share
Earnings Per Common Share	​ Note 15—Earnings Per Common Share ​ The following table sets forth the computation of basic and diluted earnings per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars and shares in thousands, except for per share amounts) ​ 2020 ​ 2019 ​ 2018 Basic earnings per common share: ​ ​ ​ ​ Net income ​ ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 Weighted-average basic common shares ​ ​ ​ 54,756 ​ ​ 34,561 ​ ​ 36,530 Basic earnings per common share ​ ​ $ 2.20 ​ $ 5.40 ​ $ 4.90 Basic earnings per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income ​ ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 Weighted-average basic common shares ​ ​ ​ 54,756 ​ ​ 34,561 ​ ​ 36,530 Effect of dilutive securities ​ ​ ​ 307 ​ ​ 236 ​ ​ 246 Weighted-average dilutive shares ​ ​ ​ 55,063 ​ ​ 34,797 ​ ​ 36,776 Basic earnings per common share ​ ​ $ 2.19 ​ $ 5.36 ​ $ 4.86 ​ The calculation of diluted earnings per common share excludes outstanding stock options for which the results would have been antidilutive under the treasury stock method as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Number of shares ​ ​ ​ ​ ​ 136,844 ​ ​ ​ 62,235 ​ ​ ​ ​ 62,235 Range of exercise prices ​ ​ $ 61.42 to $ 91.35 ​ $ 87.30 to $ 91.35 ​ $ 87.30 to $ 91.35 ​ ​

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss)	Note 16—Accumulated Other Comprehensive Income (Loss) The changes in each component of accumulated other comprehensive income (loss), net of tax, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unrealized Gains ​ ​ ​ ​ ​ ​ ​ ​ ​ and Losses ​ Gains and ​ ​ ​ ​ ​ ​ ​ ​ on Securities ​ Losses on ​ ​ ​ ​ ​ Benefit ​ Available ​ Cash Flow ​ ​ ​ (Dollars in thousands) ​ Plans ​ for Sale ​ Hedges ​ Total Balance at December 31, 2017 ​ $ (5,998) ​ $ (4,278) ​ $ (151) ​ $ (10,427) Other comprehensive income (loss) before reclassifications ​ 382 ​ ​ (13,479) ​ ​ 33 ​ (13,064) Amounts reclassified from accumulated other comprehensive loss ​ 926 ​ ​ 510 ​ ​ 121 ​ 1,557 Net comprehensive income (loss) ​ 1,308 ​ (12,969) ​ 154 ​ (11,507) AOCI reclassification to retained earnings from the adoption of ASU 2018-02 ​ ​ (1,760) ​ ​ (1,147) ​ ​ (40) ​ (2,947) Balance at December 31, 2018 ​ (6,450) ​ ​ (18,394) ​ ​ (37) ​ (24,881) Other comprehensive income (loss) before reclassifications ​ 20 ​ ​ 28,245 ​ ​ (10,447) ​ 17,818 Amounts reclassified from accumulated other comprehensive income ​ 6,281 ​ ​ 2,071 ​ ​ (272) ​ 8,080 Net comprehensive income (loss) ​ 6,301 ​ 30,316 ​ (10,719) ​ 25,898 Balance at December 31, 2019 ​ (149) ​ 11,922 ​ (10,756) ​ 1,017 Other comprehensive income (loss) before reclassifications ​ (119) ​ 35,857 ​ (26,140) ​ 9,598 Amounts reclassified from accumulated other comprehensive income ​ 117 ​ (39) ​ 36,896 ​ 36,974 Net comprehensive income (loss) ​ (2) ​ 35,818 ​ 10,756 ​ 46,572 Balance at December 31, 2020 ​ $ (151) ​ $ 47,740 ​ $ — ​ $ 47,589 ​ The table below presents the reclassifications out of accumulated other comprehensive income, net of tax: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount Reclassified from Accumulated ​ ​ ​ (Dollars in thousands) ​ ​ For the Years Ended December 31, ​ ​ ​ Accumulated Other Comprehensive Income (Loss) Component ​ 2020 2019 2018 ​ Income Statement (Gains) losses on cash flow hedges: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts ​ ​ $ 47,303 ​ $ (349) ​ $ 155 ​ Interest expense ​ ​ ​ ​ (10,407) ​ 77 ​ ​ (34) ​ Provision for income taxes ​ ​ ​ ​ 36,896 ​ (272) ​ ​ 121 ​ Net income (Gains) losses on sales of available-for-sale securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ (50) ​ $ 2,655 ​ $ 655 ​ ​ Securities gains (losses), net ​ ​ ​ ​ 11 ​ ​ (584) ​ ​ (145) ​ ​ Provision for income taxes ​ ​ ​ ​ (39) ​ ​ 2,071 ​ ​ 510 ​ ​ Net income Losses and amortization of defined benefit pension: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Actuarial losses ​ ​ $ 152 ​ $ 8,053 ​ $ 1,187 ​ Salaries and employee benefits ​ ​ ​ ​ (35) ​ (1,772) ​ ​ (261) ​ Provision for income taxes ​ ​ ​ ​ 117 ​ 6,281 ​ ​ 926 ​ Net income Total reclassifications for the period ​ ​ $ 36,974 ​ $ 8,080 ​ $ 1,557 ​ ​ ​ ​

Restrictions on Subsidiary Divi

Restrictions on Subsidiary Dividends, Loans, or Advances	12 Months Ended
	Dec. 31, 2020
Restrictions on Subsidiary Dividends, Loans, or Advances
Restrictions on Subsidiary Dividends, Loans, or Advances.	Note 17—Restrictions on Subsidiary Dividends, Loans, or Advances The Company pays cash dividends to shareholders from its assets, which are mainly provided by dividends from its banking subsidiary. However, certain restrictions exist regarding the ability of its subsidiary to transfer funds to the Company in form of cash dividends, loans or advances. Prior to the merger with CSFL, the Bank was required to get the approval of the South Carolina Board of Financial Institutions (“SCBFI”) to pay dividends that exceeds 100% of net income in any calendar year. With the merger with CSFL, the Bank became a national bank regulated by the OCC. The approval of the OCC is required if the total of all dividends declared by a national bank in any calendar year exceeds the total of its net profits for that year combined with its retained net profits for the preceding two years, less any required transfers to surplus. ​ During first quarter of 2020, the Bank paid special dividends to the Company totaling $24.7 million for which SCBFI approval was not required. These funds were used to repurchase Company stock on the open market totaling $24.7 million during the first quarter of 2020. The Bank also paid a special dividend of $33.0 million during the first quarter of 2020 to provide the Company more general operating liquidity during the COVID pandemic. The Bank paid approximately $32 million to fund quarterly shareholder divided payments. During 2019, the Bank paid special dividends to the Company totaling $157.0 million for which SCBFI approval was required. The Bank received approval from the SCBFI in June 2019 to pay an additional $60.0 million above current year net income in dividends to the Company. These funds were used to repurchase Company stock on the open market totaling $156.9 million during 2019. In 2018, the Bank paid special dividends to the Company totaling $66.6 million for which SCBFI approval was not required. These funds were used to repurchase Company stock on the open market totaling $68.4 million in the third and fourth quarters of 2018. Under Federal Reserve regulations, the bank is also limited as to the amount it may lend to the Company. The maximum amount available for transfer from the bank to the Company in the form of loans or advances was approximately $479.5 million and $246.4 million at December 31, 2020 and 2019, respectively.

Retirement Plans

Retirement Plans	12 Months Ended
	Dec. 31, 2020
Retirement Plans
Retirement Plans	Note 18—Retirement Plans The Company and its subsidiary had a non-contributory defined benefit pension plan covering all employees hired on or before December 31, 2005, who have attained age 21 of eligible service. The Company’s funding policy on the pension plan was based principally, among other considerations, on contributing an amount necessary to satisfy the Internal Revenue Service’s funding standards. Effective July 1, 2009, the Company suspended the accrual of benefits for pension plan participants under the non- contributory defined benefit plan. The plan was terminated in the second quarter of 2019. During 2018, we made the decision to terminate the non-contributory defined benefit pension plan. We received approval from the IRS through a determination letter in the fourth quarter of 2018 to proceed with the termination. The termination of the pension plan was recorded during the second quarter of 2019 and distributions of assets from the plan were fully paid out by the fourth quarter of 2019. During the second quarter of 2019, the Company recorded a charge of $9.5 million related to the termination of the pension plan in the consolidated statement of income. This cost was the result of the recognition of the pre-tax losses from the pension plan that were recorded and held in accumulated other comprehensive income of $7.7 million and the write-off of the pension plan asset of $1.8 million. Participants had the option to be fully paid out in a lump sum or be paid through an annuity over time. If the participant chose the annuity, the funds were placed in an annuity product with a third party. The following sets forth the pension plan’s funded status and amounts recognized in the Company’s accompanying consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Change in benefit obligation: ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ — ​ $ 28,906 ​ $ 31,500 ​ Service cost ​ ​ — ​ ​ 121 ​ ​ 77 ​ Interest cost ​ — ​ 1,158 ​ 1,080 ​ Actuarial (gain) loss ​ — ​ 2,471 ​ (2,442) ​ Benefits paid ​ — ​ (538) ​ (1,188) ​ Expenses ​ ​ — ​ ​ (318) ​ ​ (121) ​ Plan termination settlements ​ ​ — ​ ​ (31,800) ​ ​ — ​ Benefit obligation at end of year ​ — ​ — ​ 28,906 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ — ​ 30,545 ​ 31,387 ​ Actual return on plan assets ​ — ​ 2,111 ​ 467 ​ Benefits paid ​ — ​ (538) ​ (1,188) ​ Expenses ​ ​ — ​ ​ (318) ​ ​ (121) ​ Plan termination settlements ​ ​ — ​ ​ (31,800) ​ ​ — ​ Fair value of plan assets at end of year ​ — ​ — ​ 30,545 ​ Funded (unfunded) status ​ $ — ​ $ — ​ $ 1,639 ​ ​ At December 31, 2020 and 2019, there were no net losses recognized in accumulated other comprehensive income excluding related income tax effects. The components of net periodic pension cost and other amounts recognized in other comprehensive income are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Interest cost $ — $ 1,157 $ 1,079 Service cost ​ ​ — ​ ​ 121 ​ ​ 78 Expected return on plan assets ​ — ​ (2,361) ​ (2,328) Recognized net actuarial loss ​ — ​ 483 ​ 775 Net periodic pension benefit ​ — ​ (600) ​ (396) Plan termination settlement ​ ​ — ​ ​ 10,126 ​ ​ — Net periodic pension cost with settlement ​ ​ — ​ ​ 9,526 ​ ​ — Net (gain) loss ​ — ​ 2,722 ​ (581) Amortization of net gain ​ — ​ (483) ​ (775) Plan termination settlement adjustment ​ ​ — ​ ​ (10,126) ​ ​ — Total amount recognized in other comprehensive income ​ — ​ (7,887) ​ (1,356) Total recognized in net periodic benefit cost and other comprehensive income ​ $ — ​ $ 1,639 ​ $ (1,752) ​ Due to the termination of the pension plan in 2019, there was no benefit obligation or plan assets at December 31, 2020 and 2019. The weighted-average assumptions used to determine net periodic pension cost are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended ​ ​ December 31, ​ ​ 2020 ​ 2019 ​ 2018 Discount rate — % 4.10 % 3.50 % Expected long-term return on plan assets — % 7.75 % 7.75 % ​ For the years ended December 31, 2019 and 2018, the discount rate of 4.10% and 3.50%, respectively, was determined by matching the projected benefit obligation cash flows of the plan to an independently derived yield curve, to arrive at the single equivalent rate. The policy, as established by the Investment Committee of the Defined Benefit Pension Plan, sought to maximize return within reasonable and prudent levels of risk. The overall long- term objective of the Plan was to achieve a rate of return that exceeds the actuarially assumed rate of return. The investment policy was reviewed on a regular basis and revised when appropriate based on the legal or regulatory environment, market trends, or other fundamental factors. In determining the long- term rate of return for the pension plan, the Company considered historical rates of return and the nature of the plan’s investments. Prior to making the decision to terminate the Plan, the Plan assets were divided among various investment classes with allowable allocation percentages as follows: Equities 55 - 65%, Fixed Income 20 - 40%, Cash Equivalents 0 - 35%. During 2019 before the termination of the pension plan, approximately 98% of pension plan assets were invested with Fixed Income Assets, and approximately 2 % of pension plan assets were held in cash equivalents. When the decision was made to terminate the plan, the Investment Committee and the Company made the decision to move the Plan assets into less risky investments of Cash Equivalents and Fixed Income Assets and out of Equities. At December 31, 2018, the Plan did not include any of the Company’s common stock. The plan made no purchases of the Company’s stock during 2020, 2019 and 2018. The difference between actual and expected returns on plan assets was accumulated and amortized over future periods and, therefore, affects the recognized expenses in such future periods. ​ Expenses incurred and charged against operations with regard to all of the Company’s retirement plans were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Pension $ — $ — $ (309) ​ Pension plan termination expense ​ ​ — ​ ​ 9,526 ​ ​ — ​ Employee savings plan/ 401(k) ​ 10,962 ​ 6,659 ​ 7,948 ​ Supplemental executive retirement plan ​ 2,862 ​ 2,343 ​ 368 ​ Post-retirement benefits ​ 43 ​ 144 ​ 254 ​ ​ ​ $ 13,867 ​ $ 18,672 ​ $ 8,261 ​ ​ The Company and its subsidiaries have a Safe Harbor plan. Under the plan, electing employees are eligible to participate after attaining age 18 . Plan participants elect to contribute portions of their annual base compensation in any combination of pre-tax deferrals or Roth post- tax deferrals subject to the annual IRS limit. Employer contributions may be made from current or accumulated net profits. Participants may elect to contribute 1% to 50 % of annual base compensation as a before tax contribution. Employees participating in the plan receive a 100% matching of their 401(k) plan contribution, up to 4 % of salary. Effective January 1, 2018, employees are eligible for an additional 2% discretionary matching contribution contingent upon achievement of the Company’s annual financial goals and payable the first quarter of the following year. Based on our financial performance in 2020, we do not expect to pay a discretionary matching contribution in the first quarter of 2021. As a result of the merger with CSFL, all former CSFL employees became eligible to participate in the Company’s 401(k) plan as of legal close. CSFL’s existing 401(k) plan balances were merged into the Company’s 401(k) plan at the end of the current year. Employees hired on January 1, 2006 or thereafter will not participate in the defined benefit pension plan, but are eligible to participate in the employees’ savings plan. Employees can enter the savings plan on or after the first day of each month. The employee may enter into a salary deferral agreement at any time to select an alternative deferral amount or to elect not to defer in the Plan. If the employee does not elect an investment allocation, the plan administrator will select a retirement- based portfolio according to the employee’s number of years until normal retirement age. The plan’s investment valuations are generally provided on a daily basis.

Post-Retirement Benefits

Post-Retirement Benefits	12 Months Ended
	Dec. 31, 2020
Post-Retirement Benefits
Post-Retirement Benefits	Note 19—Post-Retirement Benefits At December 31, 2020, the Company and its subsidiary have two post-retirement health and life insurance benefit plans, South State Bank Retiree Medical Plan (the “retiree medical plan”) and the First Federal Retiree Welfare Plan (the “retiree welfare plan”). Retiree Medical Plan Under the retiree medical plan, post-retirement health and life insurance benefits are provided to eligible employees, such benefits being limited to those employees of the Company eligible for early retirement under the pension plan on or before December 31, 1993, and former employees who are currently receiving benefits. The plan was unfunded at December 31, 2020, and the liability for future benefits has been recorded in the consolidated financial statements. The following sets forth the retiree medical plan’s funded status and amounts recognized in the Company’s accompanying consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Change in benefit obligation: ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ 254 ​ $ 309 ​ $ 337 ​ Interest cost ​ 6 ​ 11 ​ 11 ​ Actuarial loss ​ (19) ​ (33) ​ 2 ​ Benefits paid ​ (32) ​ (33) ​ (41) ​ Benefit obligation at end of year ​ 209 ​ 254 ​ 309 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ — ​ — ​ — ​ Employer contribution ​ 32 ​ 33 ​ 41 ​ Benefits paid ​ (32) ​ (33) ​ (41) ​ Fair value of plan assets at end of year ​ — ​ — ​ — ​ Funded status ​ $ (209) ​ $ (254) ​ $ (309) ​ ​ Weighted-average assumptions used to determine benefit obligations and net periodic benefit cost are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2020 ​ 2019 ​ 2018 Weighted-average assumptions used to determine benefit obligation at December 31: ​ Discount rate 1.60 % 2.70 % 3.80 % Weighted-average assumptions used to determine net periodic benefit cost for years ended December 31: ​ ​ ​ ​ ​ ​ ​ Discount rate 2.70 % 3.80 % 3.20 % Assumed health care cost trend rates at December 31: ​ ​ ​ ​ ​ ​ ​ Health care cost trend rate assumed for next year 5.00 % 5.00 % 5.00 % ​ Components of net periodic benefit cost and other amounts recognized in other comprehensive income are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Interest cost $ 6 $ 11 $ 10 ​ Recognized net actuarial loss ​ 2 ​ 6 ​ 6 ​ Net periodic benefit cost ​ 8 ​ 17 ​ 16 ​ Net (gain) loss ​ (19) ​ (33) ​ 2 ​ Amortization of gain ​ (2) ​ (6) ​ (6) ​ Total amount recognized in other comprehensive income ​ (21) ​ (39) ​ (4) ​ Total recognized in net periodic benefit cost and other comprehensive income ​ $ (13) ​ $ (22) ​ $ 12 ​ ​ There is no estimated net loss for the retiree medical plan that will be amortized from other comprehensive income into periodic benefit cost over the next fiscal year. Assumed health care cost trend rates have a significant effect on the amounts reported for the post- retirement benefit plan. A one-percentage point change in assumed health care cost trend rates would have the following effects at the end of 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One-Percentage Point (Dollars in thousands) ​ Increase ​ Decrease Effect on total of interest cost $ 1 $ (1) ​ Effect on postretirement benefit obligation ​ 10 ​ (10) ​ ​ Estimated future benefit payments (including expected future service as appropriate): ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2021 ​ $ 27 ​ 2022 ​ 25 ​ 2023 ​ 24 ​ 2024 ​ 22 ​ 2025 ​ 20 ​ 2026-2030 ​ 71 ​ ​ ​ $ 189 ​ ​ The Company expects to contribute approximately $27,000 to the retiree medical plan in 2021. Retiree Welfare Plan Under the retiree welfare plan, post-retirement health and life insurance benefits are provided to eligible employees, such benefits being limited to retired First Financial Holdings, Inc. employees who are currently receiving benefits. The plan was unfunded at December 31, 2020, and the liability for future benefits has been recorded in the consolidated financial statements. The following sets forth the retiree welfare plan’s funded status and amounts recognized in the Company’s accompanying consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2020 2019 2018 ​ Change in benefit obligation: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ 2,109 ​ $ 2,281 ​ $ 2,392 ​ Interest cost ​ ​ 54 ​ 82 ​ 73 ​ Actuarial loss ​ ​ 180 ​ 7 ​ 89 ​ Benefits paid ​ ​ (285) ​ (273) ​ (286) ​ Less: Federal subsidy on benefits paid ​ ​ 12 ​ 12 ​ 13 ​ Benefit obligation at end of year ​ ​ 2,070 ​ 2,109 ​ 2,281 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ ​ — ​ — ​ — ​ Employer contribution ​ ​ 273 ​ 261 ​ 286 ​ Participants’ contributions ​ ​ 12 ​ 12 ​ — ​ Benefits paid ​ ​ (285) ​ (273) ​ (286) ​ Fair value of plan assets at end of year ​ ​ — ​ — ​ — ​ Funded status ​ $ (2,070) ​ $ (2,109) ​ $ (2,281) ​ ​ Weighted-average assumptions used to determine benefit obligations and net periodic benefit cost are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2020 2019 ​ 2018 ​ Weighted-average assumptions used to determine benefit obligation at December 31: ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 1.60 % 2.70 % 3.80 % Weighted-average assumptions used to determine net periodic benefit cost for years ended December 31: ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 2.70 % 3.80 % 3.20 % Assumed health care cost trend rates at December 31: ​ ​ ​ ​ ​ ​ ​ Health care cost trend rate assumed for next year ​ 5.00 % 5.00 % 5.00 % ​ Components of net periodic benefit cost and other amounts recognized in other comprehensive income are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) 2020 2019 2018 Interest cost ​ $ 54 ​ $ 82 ​ $ 73 ​ Recognized net actuarial loss ​ ​ 151 ​ 160 ​ 154 ​ Net periodic benefit cost ​ ​ 205 ​ 242 ​ 227 ​ Net loss ​ ​ 180 ​ 7 ​ 89 ​ Amortization of loss ​ ​ (151) ​ (160) ​ (154) ​ Total amount recognized in other comprehensive income ​ ​ 29 ​ (153) ​ (65) ​ Total recognized in net periodic benefit cost and other comprehensive income ​ $ 234 ​ $ 89 ​ $ 162 ​ ​ The estimated net loss for the retiree welfare plan that will be amortized from other comprehensive income into periodic benefit cost over the next fiscal year is $174,000. Assumed health care cost trend rates have a significant effect on the amounts reported for the post-retirement benefit plan. A one-percentage point change in assumed health care cost trend rates would have the following effects at the end of 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One-Percentage Point (Dollars in thousands) ​ Increase ​ Decrease Effect on aggregate service and interest cost $ 4 $ (3) ​ Effect on postretirement benefit obligation ​ ​ 125 ​ ​ (114) ​ ​ Estimated future benefit payments (including expected future service as appropriate): ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2021 ​ $ 243 ​ 2022 ​ 229 ​ 2023 ​ 213 ​ 2024 ​ 198 ​ 2025 ​ 181 ​ 2026-2030 ​ 671 ​ ​ ​ $ 1,735 ​ ​ The Company expects to contribute approximately $243,000 to the retiree welfare plan in 2021.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-Based Compensation
Share-Based Compensation	Note 20—Share-Based Compensation Compensation cost is recognized for stock options and restricted stock awards issued to employees. Compensation cost is measured as the fair value of these awards on their date of grant. A Black- Scholes model is utilized to estimate the fair value of stock options, while the market price of the Company’s common stock at the date of grant is used as the fair value of restricted stock awards. Compensation cost is recognized over the required service period, generally defined as the vesting period for stock option awards and as the restriction period for restricted stock awards. For awards with graded vesting, compensation cost is recognized on a straight-line basis over the requisite service period for the entire award. Our 2004, 2012, 2019 and 2020 share-based compensation plans are long-term retention plans intended to attract, retain, and provide incentives for key employees and non-employee directors in the form of incentive and non-qualified stock options, restricted stock, and restricted stock units (“RSUs”). Our 2020 plan was adopted by our shareholders at our annual meeting on October 29, 2020. The Company assumed the obligations of CSFL under various equity incentive plans pursuant to the merger of CSFL on June 7, 2020. ​ Stock Options With the exception of non-qualified stock options granted to directors under the 2004 and 2012 plans, which in some cases may be exercised at any time prior to expiration and in some other cases may be exercised at intervals less than a year following the grant date, incentive stock options granted under our 2004, 2012, 2019 and 2020 plans may not be exercised in whole or in part within a year following the date of the grant, as these incentive stock options become exercisable in 25% increments pro ratably over the four-year period following the grant date. The options are granted at an exercise price at least equal to the fair value of the common stock at the date of grant and expire ten years from the date of grant. No options were granted under the 2004 plan after January 26, 2012, and the 2004 plan is closed other than for any options still unexercised and outstanding. options were granted under the 2012 plan after February 1, 2019, and the 2012 plan is closed other than for any options still unexercised and outstanding. options were granted under the 2019 plan after October 29, 2020, and the 2019 plan is closed other than for any options still unexercised and outstanding. The 2020 plan is the only plan from which new share- based compensation grants may be issued. It is the Company’s policy to grant options out of the 2,072,245 shares registered under the 2020 plan. Activity in the Company’s stock option plans is summarized in the following table. All information has been retroactively adjusted for stock dividends and stock splits. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2020 ​ 2019 ​ 2018 ​ ​ ​ ​ ​ Weighted ​ ​ ​ Weighted ​ ​ ​ Weighted ​ ​ ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ Shares ​ Price ​ Shares ​ Price ​ Shares ​ Price Outstanding at January 1, 2020 ​ 176,888 $ 67.14 213,866 $ 61.28 218,689 $ 52.75 ​ Granted ​ — ​ — ​ — ​ — ​ 34,407 ​ 91.05 ​ Assumed stock options and warrants from CSFL merger ​ ​ 136,831 ​ ​ 37.85 ​ — ​ ​ — ​ — ​ ​ — ​ Exercised ​ (52,331) ​ 32.12 ​ (36,978) ​ 33.26 ​ (33,424) ​ 30.88 ​ Forfeited ​ (4,963) ​ 48.89 ​ — ​ — ​ (5,806) ​ 91.35 ​ Outstanding at December 31, 2020 ​ 256,425 ​ 59.01 ​ 176,888 ​ 67.14 ​ 213,866 ​ 61.28 ​ Exercisable at December 31, 2020 ​ 256,425 ​ 59.01 ​ 131,216 ​ 60.12 ​ 140,115 ​ 49.41 ​ Weighted-average fair value of options granted during the year ​ ​ ​ ​ $ — ​ ​ ​ $ — ​ ​ ​ $ 28.01 ​ ​ The aggregate intrinsic value of 256,425, 176,888, and 213,866 stock options outstanding at December 31, 2020, 2019, and 2018 was $4.6 million, $3.7 million, and $1.9 million, respectively. The aggregate intrinsic value of 256,425, million, respectively. The aggregate intrinsic value of 52,331, 36,978, and Information pertaining to options outstanding at December 31, 2020, is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ ​ ​ ​ ​ Remaining ​ Weighted ​ ​ ​ Weighted ​ Remaining ​ Range of ​ Number ​ Contractual ​ Average ​ Number ​ Average ​ Contractual ​ Exercise Prices ​ Outstanding ​ Life ​ Exercise Price ​ Outstanding ​ Exercise Price ​ Life ​ $ 19.16 - $ 40.00 45,002 3.1 years ​ $ 31.11 45,002 ​ $ 31.11 3.1 years $ 40.01 - $ 55.00 74,579 7.7 years ​ $ 44.46 74,579 ​ $ 44.46 ​ 7.7 years $ 55.01 - $ 70.00 74,609 4.1 years ​ $ 63.61 74,609 ​ $ 63.61 ​ 4.1 years $ 70.01 - $ 85.00 ​ — ​ — years ​ $ — ​ — ​ $ — ​ — years $ 85.01 - $ 91.35 62,235 6.6 years ​ $ 91.12 ​ 62,235 ​ $ 91.12 ​ 6.6 years ​ ​ ​ ​ ​ 256,425 4.5 years ​ $ 59.01 256,425 ​ $ 59.01 4.5 years ​ The fair value of options is estimated at the date of grant using the Black-Scholes option pricing model and expensed over the options’ vesting periods. The following weighted- average assumptions were used in valuing options issued: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2020 ​ 2019 2018 Dividend yield ​ — % ​ ​ — % 1.46 % Expected life — years ​ ​ — years 8.5 years Expected volatility — % ​ — % 28.0 % Risk-free interest rate — % ​ — % 2.54 % ​ As of December 31, 2020, there was no unrecognized compensation cost related to non- vested stock option grants under the plans. The total fair value of shares vested during the years ended December 31, 2020, 2019 and 2018 was approximately $1.4 million, $799,000, and $700,000 , respectively. Compensation expense of $720,000, $641,000, and $751,000 was recorded in 2020, 2019, and 2018, respectively. Of the expense in 2020, approximately $481,000 was recognized in June 2020 due to the acceleration of vesting of stock options through the merger with CSFL. Restricted Stock We from time-to-time also grant shares of restricted stock to key employees and non-employee directors. These awards help align the interests of these employees and directors with the interests of our shareholders by providing economic value directly related to increases in the value of our stock. The value of the stock awarded is established as the fair market value of the stock at the time of the grant. We recognize expenses, equal to the total value of such awards, ratably over the vesting period of the stock grants. Restricted stock grants to employees typically “cliff vest” after four years . Grants to non-employee directors typically vest within a 12-month period. ​ All restricted stock agreements are conditioned upon continued employment, or service in the case of directors. Termination of employment prior to a vesting date, as described below, would terminate any interest in non-vested shares. Prior to vesting of the shares, as long as employed by the Company, the key employees and non-employee directors will have the right to vote such shares and to receive dividends paid with respect to such shares. All restricted shares will fully vest in the event of change in control of the Company or upon the death of the recipient. Due to the merger between the Company and CSFL effective June 7, 2020, a total of 29,303 restricted stock awards became fully vested. Non-vested restricted stock for the year ended December 31, 2020 is summarized in the following table. All information has been retroactively adjusted for stock dividends and stock splits. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date Restricted Stock ​ Shares ​ Fair Value Nonvested at January 1, 2020 69,450 ​ $ 58.96 ​ Assumed restricted stock shares from CSFL merger ​ 9,755 ​ ​ 60.27 ​ Granted 9,145 ​ 55.96 ​ Vested (77,029) ​ 58.67 ​ Forfeited (317) ​ 65.86 ​ Nonvested at December 31, 2020 11,004 ​ $ 59.42 ​ ​ The Company granted 9,145, 8,934, and 7,836 shares for the years ended December 31, 2020, 2019, and 2018, respectively. The weighted-average- grant-date fair value of restricted shares granted in 2020, 2019, and 2018 was $55.96, , respectively. Compensation expense of $1.5 million, $1.7 million, and $2.5 million was recorded in 2020, 2019, and 2018, respectively. Of the expense in 2020, approximately $704,000 was recognized in June 2020 due to the acceleration of vesting of restricted stock awards through the merger with CSFL. The vesting schedule of these shares as of December 31, 2020 is as follows: ​ ​ ​ ​ ​ ​ Shares 2021 7,935 ​ 2022 751 ​ 2023 751 ​ 2024 1,567 ​ 2025 — ​ Thereafter — ​ ​ 11,004 ​ ​ As of December 31, 2020, there was $537,000 thousand of total unrecognized compensation cost related to non- vested restricted stock granted under the plans. The cost is expected to be recognized over a weighted-average period of 1.61 years as of December 31, 2020. The total fair value of shares vested during the years ended December 31, 2020, 2019 and 2018 was approximately $4.6 million, $3.0 million, and $2.5 million, respectively. Restricted Stock Units (“RSU”) We, from time-to-time, also grant performance RSUs and time-vested RSUs to key employees. These awards help align the interests of these employees with the interests of our shareholders by providing economic value directly related to our performance. Some performance RSU grants contain a three-year performance period while others contain a one-year performance period and a time-vested requirement (generally four years from the grant date). We communicate threshold, target, and maximum performance RSU awards and performance targets to the applicable key employees at the beginning of a performance period. Due to the merger with CSFL, all legacy and assumed performance based restricted stock units converted to a time-vesting requirement. Dividends are not paid in respect to the awards during the performance or time-vested period. The value of the RSUs awarded is established as the fair market value of the stock at the time of the grant. We recognize expenses on a straight-line basis typically over the performance and vesting/or time-vesting periods based upon the probable performance target, as applicable, that will be met. For the year ended December 31 2020, we accrued for 100.0 % of the RSUs granted. Due to the merger between the Company and CSFL effective June 7, 2020, a total of 242,018 restricted stock units became fully vested. Nonvested RSUs for the year ended December 31, 2020 is summarized in the following table. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date Restricted Stock Units ​ Shares ​ Fair Value Nonvested at January 1, 2020 324,601 ​ $ 76.44 ​ Assumed restricted stock units from CSFL merger ​ 388,381 ​ ​ 60.27 ​ Granted 382,205 ​ 61.27 ​ Vested ​ (275,661) ​ ​ 75.63 ​ Forfeited ​ (68,705) ​ ​ 74.09 ​ Nonvested at December 31, 2020 750,821 ​ $ 60.88 ​ ​ The nonvested shares of 750,821 at December 31, 2020 includes 61,123 shares that have met their three year vesting period, however, there is still a two year hold on these shares. These shares should be fully vested with the hold lifted by 2023. The Company granted 382,205, 159,521, and 113,270 shares for the year ended December 31, 2020, 2019, and 2018, respectively. The weighted-average grant-date fair value of restricted stock units granted in 2020 was $61.27. Compensation expense of $21.0 million, $6.4 million, and $5.5 million was recorded in 2020, 2019, and 2018, respectively. Of the expense in 2020, approximately $7.5 million was recognized in June 2020 due to the acceleration of vesting of restricted stock units through the merger with CSFL. As of December 31, 2020, there was $27.7 million of total unrecognized compensation cost related to nonvested RSUs granted under the plan. This cost is expected to be recognized over a weighted-average period of 2.8 years as of December 31, 2020. The total fair value of restricted stock units that vested during the years ended December 31, 2020, 2019, and 2018 was approximately $23.6 million, $5.8 million, and $5.7 million, respectively. Employee Stock Purchase Plan The Company has registered 363,825 shares of common stock in connection with the establishment of an Employee Stock Purchase Plan. At the annual shareholders meeting on October 29, 2020, a proposal was adopted that increased the shares of common stock that may be issued under the plan by up to 1,400,000 shares. The plan is available to all employees who have attained age 21 and completed six months of service. The Company currently has more than 1.4 million shares available for issuances under the plan. The price at which common stock may be purchased for each quarterly option period is the lesser of 95% of the common stock’s fair value on either the first or last day of the quarter. The 2002 Employee Stock Purchase Plan permits eligible employees to purchase Company stock at a discounted price. Beginning July 1, 2009, the 15% discount was reduced to 5%. The Company recognized $81,000, $75,000 and $82,000 in share-based compensation expense for the years ended December 31, 2020, 2019 and 2018, respectively.

Stock Repurchase Program

Stock Repurchase Program	12 Months Ended
	Dec. 31, 2020
Stock Repurchase Program
Stock Repurchase Program	Note 21—Stock Repurchase Program In February 2004, we announced a program with no formal expiration date to repurchase up to 250,000 of our common shares. In March 2017, the Board of Directors approved and reset the number of shares available to be repurchased under the 2004 stock repurchase program to 1,000,000 , all of which had been repurchased as of December 31, 2018. In January 2019, the Board of Directors approved a new program (“2019 repurchase program”) to repurchase up to an additional of our common shares, all of which had been repurchased as of June 30, 2019. In June 2019, the Board of Directors authorized an additional of our common shares to be repurchased under the 2019 repurchase program, however we are not obligated to repurchase any additional shares under the 2019 repurchase program. As of December 31, 2020, we have repurchased . In 2020, the Company repurchased a total of per share (excluding commission expense). In 2019, the Company repurchased a total of per share (excluding commission expense). The remaining shares (authorized in June of 2019) have expired. See Note 32 — and 2018, respectively. Of the amounts in 2020, 86,263 shares at a cost of $5.2 million were related to the vesting of restricted stock due to the merger with CSFL.

Lease Commitments

Lease Commitments	12 Months Ended
	Dec. 31, 2020
Leases
Lease Commitments	Note 22—Lease Commitments On January 1, 2019, we adopted the requirements of Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842). The purpose of the update was to increase transparency and comparability between organizations that enter into lease agreements. The key difference between the previous guidance and the update is the recognition of a right-of-use asset (ROU) and lease liability on the statement of financial position for those leases previously classified as operating leases under the old guidance. Accounting Standards Codification (“ASC”). Our lease agreements in which ASC Topic 842 has been applied are primarily for real estate properties, including retail branch locations, operations and administration locations and stand-alone ATM locations. We performed an analysis on equipment leases for the implementation of ASC Topic 842 and determined the number and dollar amount of our equipment leases was not material. ​ A modified retrospective transition approach is required, applying the new standard to all leases existing at the date of initial application. An entity may choose to use either (1) its effective date or (2) the beginning of the earliest comparative period presented in the financial statements as its date of initial application. We chose the transition method of adoption where we initially apply the new lease standard at the effective date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption if applicable. Therefore, we applied this standard to all existing leases as of the adoption date of January 1, 2019, recording a ROU asset and a lease liability in an equal amount. We recorded a ROU asset and lease liability million at the commencement date of January 1, 2019. We did not have a cumulative-effect adjustment to the opening balance of retained earnings at commencement and the adoption of ASC Topic 842 did not have a material impact on our consolidated income statement. ​ As of December 31, 2020 and 2019, we had operating ROU assets of $113.4 million and $87.4 million, respectively, and operating lease liabilities of $118.3 million and $88.8 million, respectively. We maintain one . The exercise of renewal options is based on the sole judgment of management and what they consider to be reasonably certain given the environment today. Factors in determining whether an option is reasonably certain of exercise include, but are not limited to, the value of leasehold improvements, the value of renewal rate compared to market rates, and the presence of factors that would cause a significant economic penalty to us if the option is not exercised. Leases with an initial term of 12 months or less are not recorded on the balance sheet and instead are recognized in lease expense on a straight-line basis over the lease term. We do not sublease any portion of these locations to third parties. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Year Ended December 31, ​ 2020 2019 Lease Cost Components: ​ ​ ​ ​ ​ ​ ​ ​ Amortization of ROU assets - finance leases ​ $ 289 ​ $ — ​ ​ Interest on lease liabilities - finance leases ​ ​ 44 ​ ​ — ​ ​ Operating lease cost (cost resulting from lease payments) ​ ​ 14,266 ​ ​ 8,804 ​ ​ Short-term lease cost ​ ​ 404 ​ ​ 494 ​ ​ Variable lease cost (cost excluded from lease payments) ​ 1,081 ​ 430 ​ ​ Total lease cost ​ $ 16,084 ​ $ 9,728 ​ ​ Supplemental Cash Flow and Other Information Related to Leases: ​ ​ ​ ​ ​ ​ ​ ​ Finance lease - operating cash flows ​ $ 42 ​ $ — ​ ​ Finance lease - financing cash flows ​ ​ 255 ​ ​ — ​ ​ Operating lease - operating cash flows (fixed payments) ​ 12,876 ​ 7,725 ​ ​ Operating lease - operating cash flows (net change asset/liability) ​ ​ (9,123) ​ ​ 1,457 ​ ​ New ROU assets - operating leases ​ ​ 43,583 ​ ​ 10,239 ​ ​ New ROU assets - finance leases ​ ​ 5,374 ​ ​ ​ ​ ​ Weighted - average remaining lease term (years) - finance leases ​ ​ 7.40 ​ ​ ​ ​ ​ Weighted - average remaining lease term (years) - operating leases ​ 11.51 ​ 14.14 ​ ​ Weighted - average discount rate - finance leases ​ ​ 1.7% ​ ​ ​ ​ ​ Weighted - average discount rate - operating leases ​ 3.3% ​ 3.9% ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease payments due: ​ ​ ​ ​ ​ ​ ​ ​ 2021 ​ $ 15,753 ​ ​ ​ ​ 2022 ​ 14,508 ​ ​ ​ ​ 2023 ​ 13,482 ​ ​ ​ ​ 2024 ​ 12,212 ​ ​ ​ ​ 2025 ​ ​ 10,747 ​ ​ ​ ​ ​ Thereafter ​ 78,711 ​ ​ ​ ​ ​ Total undiscounted cash flows ​ 145,413 ​ ​ ​ ​ ​ Discount on cash flows ​ ​ (27,092) ​ ​ ​ ​ ​ Total operating lease liabilities ​ $ 118,321 ​ ​ ​ ​ ​ ​ As of December 31, 2020, the Company also holds a small number of finance leases assumed in connection to the CSFL merger. These leases are all real estate leases. Terms and conditions are similar to those real estate operating leases described above. Lease classifications from the acquired institutions were retained. At December 31, 2020, we do not maintain any leases with related parties, and we determined that the number and dollar amount of our equipment leases was immaterial. As of December 31, 2020, we have an additional operating lease that has not yet commenced of ​ See further discussion in Note 1 — ​

Contingent Liabilities

Contingent Liabilities	12 Months Ended
	Dec. 31, 2020
Contingent Liabilities
Contingent Liabilities	Note 23—Contingent Liabilities The Company has been named as defendant in various legal actions, arising from its normal business activities, in which damages in various amounts are claimed. The Company is also exposed to litigation risk related to the prior business activities of banks acquired through whole bank acquisitions. Although the amount of any ultimate liability with respect to such matters cannot be determined, in the opinion of management, any such liability will not have a material effect on the Company’s consolidated financial statements. The Company and its subsidiary are involved at times in certain litigation arising in the normal course of business. In the opinion of management as of December 31, 2020, there is no pending or threatened litigation that will have a material effect on the Company’s consolidated financial position or results of operations.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions
Related Party Transactions	Note 24—Related Party Transactions During 2020 and 2019, the Company’s banking subsidiary had loan and deposit relationships with certain related parties, principally directors and executive officers, their immediate families and their business interests. All of these relationships were in the ordinary course of business at rates and terms substantially consistent with similar transactions with unrelated parties. Loans outstanding to this group (including immediate families and business interests) totaled $28.7 million and $37.5 million at December 31, 2020 and 2019 respectively. During 2020, $12.4 million of new loans were made to this group while repayments of $17.7 million were received during the year. There were also additions to related party loans of $31.8 million due to the addition of new related parties through the acquisition of CSFL and there were reductions to related party loans of $35.3 million due to the removal of related parties through the acquisition of CSFL.

Financial Instruments with Off-

Financial Instruments with Off-Balance Sheet Risk	12 Months Ended
	Dec. 31, 2020
Financial Instruments with Off-Balance Sheet Risk
Financial Instruments with Off-Balance Sheet Risk	Note 25—Financial Instruments with Off-Balance Sheet Risk The Company’s subsidiary is a party to credit related financial instruments with off-balance sheet risks in the normal course of business to meet the financing needs of their customers. These financial instruments include commitments to extend credit, standby letters of credit and financial guarantees. Such commitments involve, to varying degrees, elements of credit, interest rate, or liquidity risk in excess of the amounts recognized in the consolidated balance sheets. The contract amounts of these instruments express the extent of involvement the subsidiary has in particular classes of financial instruments. The subsidiary’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit, standby letters of credit, and financial guarantees is represented by the contractual amount of those instruments. The subsidiary uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments. At December 31, 2020 and 2019, the following financial instruments, whose contract amounts represent credit risk, were outstanding: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) ​ 2020 ​ 2019 ​ Commitments to extend credit ​ $ 5,929,845 ​ $ 2,902,000 ​ Standby letters of credit and financial guarantees ​ 76,507 ​ 32,869 ​ ​ ​ $ 6,006,352 ​ $ 2,934,869 ​ ​ million and which was recorded in Other Liabilities on the Balance Sheet. — Commitments to Extend Credit Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future liquidity requirements. The Bank evaluates each customer’s credit worthiness on a case-by- case basis. The amount of collateral obtained, if deemed necessary by the bank upon extension of credit, is based on management’s credit evaluation of the customer. Collateral held varies but may include accounts receivable, inventory, property, plant and equipment, and personal guarantees. Unfunded commitments under commercial lines-of- credit, revolving credit lines and overdraft protection agreements are commitments for possible future extensions of credit to existing customers. These lines-of-credit are uncollateralized and usually do not contain a specified maturity date and may not be drawn to the extent to which the banking subsidiary is committed. Standby Letters of Credit and Financial Guarantees Standby letters of credit and financial guarantees are conditional commitments issued by the banking subsidiary to guarantee the performance of a customer to a third party. Those letters of credit and guarantees are primarily issued to support public and private borrowing arrangements. Essentially, all standby letters of credit have expiration dates within one year . The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. The amount of collateral obtained, if deemed necessary, is based on management’s credit evaluation of the customer.

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2020
Fair Value
Fair Value	Note 26—Fair Value FASB ASC 820, Fair Value Measurements and Disclosures , defines fair value, establishes a framework for measuring fair value under accounting principles generally accepted in the United States, and enhances disclosures about fair value measurements. FASB ASC 820 clarifies that fair value should be based on the assumptions market participants would use when pricing an asset or liability and establishes a fair value hierarchy that prioritizes the information used to develop those assumptions. The Company utilizes fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. Available-for-sale and trading securities, derivative contracts, and mortgage servicing rights (“MSRs”) are recorded at fair value on a recurring basis. Additionally, from time to time, we may be required to record at fair value other assets on a nonrecurring basis, such as impaired loans, OREO, and certain other assets. These nonrecurring fair value adjustments typically involve application of lower of cost or market accounting or write-downs of individual assets. FASB ASC 820 establishes a three-tier fair value hierarchy which prioritizes the inputs used in measuring fair value as follows: ​ ​ Level 1 Observable inputs such as quoted prices in active markets; Level 2 Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and Level 3 Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. The following is a description of valuation methodologies used for assets recorded at fair value. Trading Securities ​ The fair values of trading securities are determined as follows: (1) for those securities that have traded prior to the date of the consolidated balance sheet but have not settled (date of sale) until after such date, the sales price is used as the fair value; and, (2) for those securities which have not traded as of the date of the consolidated balance sheet, the fair value was determined by broker price indications of similar or same securities. Investment Securities Securities available-for-sale are valued on a recurring basis at quoted market prices where available. If quoted market prices are not available, fair values are based on quoted market prices of comparable securities. Level 1 securities include those traded on an active exchange, such as the New York Stock Exchange and The NASDAQ Stock Market. Level 2 securities include mortgage-backed securities and debentures issued by government sponsored entities, municipal bonds and corporate debt securities, or U.S. Treasury securities that are traded by dealers or brokers in active over-the-counter markets and money market funds. Securities held-to-maturity are valued at quoted market prices or dealer quotes similar to securities available-for-sale. The carrying value of FHLB and FRB stock approximates fair value based on the redemption provisions. Mortgage Loans Held for Sale Mortgage loans held for sale are carried at the fair market value with changes in fair value recognized in current period earnings. The fair values of mortgage loans held for sale are based on commitments on hand from investors within the secondary market for loans with similar characteristics. As such, the fair value adjustments for mortgage loans held for sale are recurring Level 2. Loans We do not record loans at fair value on a recurring basis. However, from time to time, a loan may be considered impaired and an ACL may be established. Loans for which it is probable that payment of interest and principal will not be made in accordance with the contractual terms of the loan agreement are considered impaired. Once a loan is identified as individually impaired, Management measures impairment using estimated fair value methodologies. The fair value of impaired loans is estimated using one of several methods, including collateral value, market value of similar debt, enterprise value, liquidation value and discounted cash flows. Those impaired loans not requiring an allowance represent loans for which the fair value of the expected repayments or collateral exceed the recorded investments in such loans. At December 31, 2020, approximately half of the impaired loans were evaluated based on the fair value of the collateral because such loans were considered collateral dependent. Impaired loans, where an allowance is established based on the fair value of collateral; require classification in the fair value hierarchy. When the fair value of the collateral is based on an observable market price or a current appraised value, we consider the impaired loan as nonrecurring Level 2. When an appraised value is not available or Management determines the fair value of the collateral is further impaired below the appraised value and there is no observable market price, we consider the impaired loan as nonrecurring Level 3. ​ Other Real Estate Owned (“OREO”) Typically, OREO, consisting of properties obtained through foreclosure or in satisfaction of loans, is reported at fair value, determined on the basis of current appraisals, comparable sales, and other estimates of value obtained principally from independent sources, adjusted for estimated selling costs (Level 2). However, OREO is considered Level 3 in the fair value hierarchy because management has qualitatively applied a discount due to the size, supply of inventory, and the incremental discounts applied to the appraisals. Management also considers other factors, including changes in absorption rates, length of time the property has been on the market, and anticipated sales values, which have resulted in adjustments to the collateral value estimates indicated in certain appraisals. At the time of foreclosure, any excess of the loan balance over the fair value of the real estate held as collateral is treated as a charge against the allowance for loan losses. Gains or losses on sale and generally any subsequent adjustments to the value are recorded as a component of OREO expense. Derivative Financial Instruments Fair value is estimated using pricing models of derivatives with similar characteristics or discounted cash flow models where future floating cash flows are projected and discounted back; and accordingly, these derivatives are classified within Level 2 of the fair value hierarchy. See Note 29—Derivative Financial Instruments for additional information. Mortgage servicing rights (“MSRs”) The estimated fair value of MSRs is obtained through an independent derivatives dealer analysis of future cash flows. The evaluation utilizes assumptions market participants would use in determining fair value including market discount rates, prepayment speeds, servicing income, servicing costs, default rates and other market driven data, as well as the market’s perception of future interest rate movements. MSRs are classified as Level 3. Assets and Liabilities Recorded at Fair Value on a Recurring Basis The tables below present the recorded amount of assets and liabilities measured at fair value on a recurring basis. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Prices ​ ​ ​ ​ ​ ​ ​ ​ ​ In Active ​ Significant ​ ​ ​ ​ ​ ​ ​ ​ Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs (Dollars in thousands) ​ Fair Value ​ (Level 1) ​ (Level 2) ​ (Level 3) December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 813,899 ​ $ — ​ $ 813,899 ​ $ — Loans held for sale ​ 290,467 ​ — ​ 290,467 ​ — Trading securities ​ 10,674 ​ — ​ 10,674 ​ — Securities available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ ​ 29,256 ​ ​ — ​ ​ 29,256 ​ ​ — State and municipal obligations ​ 520,039 ​ — ​ 520,039 ​ — Mortgage-backed securities ​ 2,767,675 ​ — ​ 2,767,675 ​ — Corporate securities ​ ​ 13,702 ​ ​ — ​ ​ 13,702 ​ ​ — Total securities available-for-sale ​ 3,330,672 ​ — ​ 3,330,672 ​ — Mortgage servicing rights ​ 43,820 ​ — ​ — ​ 43,820 ​ ​ $ 4,489,532 ​ $ — ​ $ 4,445,712 ​ $ 43,820 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 804,832 ​ $ — ​ $ 804,832 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 16,252 ​ $ — ​ $ 16,252 ​ $ — Loans held for sale ​ 59,363 ​ — ​ 59,363 ​ — Securities available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ ​ 25,941 ​ ​ — ​ ​ 25,941 ​ ​ — State and municipal obligations ​ 208,415 ​ — ​ 208,415 ​ — Mortgage-backed securities ​ 1,721,691 ​ — ​ 1,721,691 ​ — Total securities available-for-sale ​ 1,956,047 ​ — ​ 1,956,047 ​ — Mortgage servicing rights ​ 30,525 ​ — ​ — ​ 30,525 ​ ​ $ 2,062,187 ​ $ — ​ $ 2,031,662 ​ $ 30,525 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 31,273 ​ $ — ​ $ 31,273 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ There were no financial instruments transferred between Level 1 and Level 2 of the valuation hierarchy for the years ended December 31, 2020 and 2019. Changes in Level 3 Fair Value Measurements When a determination is made to classify a financial instrument within Level 3 of the valuation hierarchy, the determination is based upon the significance of the unobservable factors to the overall fair value measurement. However, since Level 3 financial instruments typically include, in addition to the unobservable or Level 3 components, observable components (that is, components that are actively quoted and can be validated to external sources), the gains and losses below include changes in fair value due in part to observable factors that are part of the valuation methodology. There were no changes in hierarchy classifications of Level 3 assets or liabilities for the year ended December 31, 2020. A reconciliation of the beginning and ending balances of Level 3 assets and liabilities recorded at fair value on a recurring basis for the years ended December 31, 2020 and 2019 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Assets Liabilities Fair value, January 1, 2020 ​ $ 30,525 ​ $ — ​ Servicing assets that resulted from transfers of financial assets ​ 28,456 ​ — ​ Changes in fair value due to valuation inputs or assumptions ​ (6,991) ​ — ​ Changes in fair value due to decay ​ (8,170) ​ — ​ Fair value, December 31, 2020 ​ $ 43,820 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value, January 1, 2019 ​ $ 34,727 ​ $ — ​ Servicing assets that resulted from transfers of financial assets ​ 7,363 ​ — ​ Changes in fair value due to valuation inputs or assumptions ​ ​ (6,976) ​ ​ — ​ Changes in fair value due to decay ​ (4,589) ​ — ​ Fair value, December 31, 2019 ​ $ 30,525 ​ $ — ​ ​ There were no unrealized losses included in accumulated other comprehensive income related to Level 3 financial assets and liabilities at December 31, 2020 or 2019. See Note 30 — Assets and Liabilities Recorded at Fair Value on a Nonrecurring Basis The tables below present the recorded amount of assets and liabilities measured at fair value on a nonrecurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Prices ​ ​ ​ ​ ​ ​ ​ ​ ​ In Active ​ Significant ​ ​ ​ ​ ​ ​ ​ ​ Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs (Dollars in thousands) ​ Fair Value ​ (Level 1) ​ (Level 2) ​ (Level 3) December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ OREO ​ $ 11,914 ​ $ — ​ $ — ​ $ 11,914 ​ Bank property held for sale ​ ​ 36,006 ​ ​ — ​ — ​ ​ 36,006 ​ Impaired loans ​ 17,609 ​ — ​ — ​ 17,609 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ OREO ​ $ 6,539 ​ $ — ​ $ — ​ $ 6,539 ​ Bank property held for sale ​ ​ 5,425 ​ ​ — ​ — ​ ​ 5,425 ​ Non-acquired impaired loans ​ 15,444 ​ — ​ — ​ 15,444 ​ ​ Quantitative Information about Level 3 Fair Value Measurements ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Average ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ Valuation Technique Unobservable Input 2020 2019 Nonrecurring measurements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Impaired loans Discounted appraisals and discounted cash flows Collateral discounts ​ 5 % ​ 2 % OREO and premises held for sale Discounted appraisals Collateral discounts and estimated costs to sell ​ 14 % ​ 31 % ​ Fair Value of Financial Instruments The following methods and assumptions were used by the Company in estimating its fair value disclosures for financial instruments. In cases where quoted market prices are not available, fair values are based on estimates using present value or other valuation techniques. Those models are significantly affected by the assumptions used, including the discount rates and estimates of future cash flows. In that regard, the derived fair value estimates cannot be substantiated by comparison to independent markets and, in many cases, could not be realized in immediate settlement of the instrument. The use of different methodologies may have a material effect on the estimated fair value amounts. The fair value estimates presented herein are based on pertinent information available to management as of December 31, 2020 and 2019. Such amounts have not been revalued for purposes of these consolidated financial statements since those dates and, therefore, current estimates of fair value may differ significantly from the amounts presented herein. The following methods and assumptions were used to estimate the fair value of each class of financial instruments for which it is practicable to estimate that value: Cash and Cash Equivalents Trading Securities The fair values of trading securities are determined as follows: (1) for those securities that have traded prior to the date of the consolidated balance sheet but have not settled (date of sale) until after such date, the sales price is used as the fair value; and, (2) for those securities which have not traded as of the date of the consolidated balance sheet, the fair value was determined by broker price indications of similar or same securities. I nvestment Securities —Securities held-to-maturity are valued at quoted market prices or dealer quotes. The carrying value of FHLB stock approximates fair value based on the redemption provisions. The carrying value of the Company’s investment in unconsolidated subsidiaries approximates fair value. See Note 4 — Loans held for sale ​ Loans — ASU 2016-01 - Financial Instruments – Overall – Recognition and Measurement of Financial Assets and Financial Liabilities became effective for us on January 1, 2018. This accounting standard requires us to calculate the fair value of our loans for disclosure purposes based on an estimated exit price. With ASU 2016-01, to estimate an exit price, all loans (fixed and variable) are being valued with a discounted cash flow analyses for loans that includes our estimate of future credit losses expected to be incurred over the life of the loans. Fair values for certain mortgage loans (e.g., one-to-four family residential) and other consumer loans are estimated using discounted cash flow analyses based on our current rates offered for new loans of the same type, structure and credit quality. Fair values for other loans (e.g., commercial real estate and investment property mortgage loans, commercial and industrial loans) are estimated using discounted cash flow analyses-using interest rates we currently offer for loans with similar terms to borrowers of similar credit quality. Fair values for non-performing loans are estimated using a discounted cash flow analysis. ​ Deposit Liabilities their carrying amounts). The carrying amounts of variable-rate, fixed- term money market accounts, and certificates of deposit approximate their fair values at the reporting date. Fair values for fixed-rate certificates of deposit are estimated using a discounted cash flow calculation that applies interest rates currently being offered on certificates to a schedule of aggregated expected monthly maturities on time deposits. Federal Funds Purchased and Securities Sold Under Agreements to Repurchase Other Borrowings Accrued Interest Derivative Financial Instruments Commitments to Extend Credit, Standby Letters of Credit and Financial Guarantees account the remaining terms of the agreements and the present creditworthiness of the counterparties. For fixed- rate loan commitments, fair value also considers the difference between current levels of interest rates and the committed rates. The fair values of guarantees and letters of credit are based on fees currently charged for similar agreements or on the estimated costs to terminate them or otherwise settle the obligations with the counterparties at the reporting date. The estimated fair value, and related carrying amount, of the Company’s financial instruments are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Fair ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Value ​ Level 1 ​ Level 2 ​ Level 3 December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financial assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 4,609,255 ​ $ 4,609,255 ​ $ 4,609,255 ​ $ — ​ $ — ​ Trading securities ​ ​ 10,674 ​ ​ 10,674 ​ ​ — ​ ​ 10,674 ​ ​ — ​ Investment securities ​ 4,446,657 ​ 4,448,300 ​ 160,443 ​ 4,287,857 ​ — ​ Loans held for sale ​ ​ 290,467 ​ ​ 290,467 ​ ​ — ​ ​ 290,467 ​ ​ — ​ Loans, net of allowance for loan losses ​ 24,206,825 ​ 24,757,859 ​ — ​ — ​ 24,757,859 ​ Accrued interest receivable ​ 107,601 ​ 107,601 ​ — ​ 12,952 ​ 94,649 ​ Mortgage servicing rights ​ 43,820 ​ 43,820 ​ — ​ — ​ 43,820 ​ Interest rate swap - non-designated hedge ​ 802,763 ​ 802,763 ​ — ​ 802,763 ​ — ​ Other derivative financial instruments (mortgage banking related) ​ 11,136 ​ 11,136 ​ — ​ 11,136 ​ — ​ Financial liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 30,693,882 ​ 30,719,416 ​ — ​ 30,719,416 ​ — ​ Federal funds purchased and securities sold under agreements to repurchase ​ 779,666 ​ 779,666 ​ — ​ 779,666 ​ — ​ Other borrowings ​ 390,179 ​ 386,126 ​ — ​ 386,126 ​ — ​ Accrued interest payable ​ 7,103 ​ 7,103 ​ — ​ 7,103 ​ — ​ Interest rate swap - non-designated hedge ​ 804,832 ​ 804,832 ​ — ​ 804,832 ​ — ​ Off balance sheet financial instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commitments to extend credit ​ — ​ 136,726 ​ — ​ 136,726 ​ — ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financial assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 688,704 ​ $ 688,704 ​ $ 688,704 ​ $ — ​ $ — ​ Investment securities ​ 2,005,171 ​ 2,005,171 ​ 49,124 ​ 1,956,047 ​ — ​ Loans held for sale ​ ​ 59,363 ​ ​ 59,363 ​ ​ — ​ ​ 59,363 ​ ​ — ​ Loans, net of allowance for loan losses ​ 11,313,113 ​ 11,452,003 ​ — ​ — ​ 11,452,003 ​ Accrued interest receivable ​ 36,774 ​ 36,774 ​ — ​ 8,500 ​ 28,274 ​ Mortgage servicing rights ​ 30,525 ​ 30,525 ​ — ​ — ​ 30,525 ​ Interest rate swap - non-designated hedge ​ 15,350 ​ 15,350 ​ — ​ 15,350 ​ — ​ Other derivative financial instruments (mortgage banking related) ​ 902 ​ 902 ​ — ​ 902 ​ — ​ Financial liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 12,177,096 ​ 11,406,477 ​ — ​ 11,406,477 ​ — ​ Federal funds purchased and securities sold under agreements to repurchase ​ 298,741 ​ 298,741 ​ — ​ 298,741 ​ — ​ Other borrowings ​ 815,936 ​ 818,210 ​ — ​ 818,210 ​ — ​ Accrued interest payable ​ 4,916 ​ 4,916 ​ — ​ 4,916 ​ — ​ Interest rate swap - non-designated hedge ​ 16,693 ​ 16,693 ​ — ​ 16,693 ​ — ​ Interest rate swap - cash flow hedge ​ 13,791 ​ 13,791 ​ — ​ 13,791 ​ — ​ Other derivative financial instruments (mortgage banking related) ​ ​ 789 ​ ​ 789 ​ — ​ 789 ​ — ​ Off balance sheet financial instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commitments to extend credit ​ ​ — ​ 36,031 ​ — ​ 36,031 ​ — ​ ​

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2020
Regulatory Matters
Regulatory Matters	Note 27—Regulatory Matters The Company is subject to regulations with respect to certain risk-based capital ratios. These risk-based capital ratios measure the relationship of capital to a combination of balance sheet and off-balance sheet risks. The values of both balance sheet and off-balance sheet items are adjusted based on the rules to reflect categorical credit risk. In addition to the risk-based capital ratios, the regulatory agencies have also established a leverage ratio for assessing capital adequacy. The leverage ratio is equal to Tier 1 capital divided by total consolidated on-balance sheet assets (minus amounts deducted from Tier 1 capital). The leverage ratio does not involve assigning risk weights to assets. ​ Under current regulations, the Company and the Bank are subject to a minimum ratio of common equity Tier 1 capital (“CET1”) to risk-weighted assets of 4.5%. and a minimum required ratio of Tier 1 capital to risk-weighted assets of 6 %. The minimum required leverage ratio is 4 %. The minimum required total capital to risk-weighted assets ratio is 8%. ​ In order to avoid restrictions on capital distributions and discretionary bonus payments to executives, under the new rules a covered banking organization is also required to maintain a “capital conservation buffer” in addition to its minimum risk-based capital requirements. This buffer is required to consist solely of CET1, and the buffer applies to all three risk-based measurements (CET1, Tier 1 capital and total capital). The capital conservation buffer became fully phased-in on January 1, 2019 and consists of an additional amount of Tier 1 common equity equal to 2.5% of risk-weighted assets. ​ The Bank is also subject to the regulatory framework for prompt corrective action, which identifies five capital categories for insured depository institutions (well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized, and critically undercapitalized) and is based on specified thresholds for each of the three risk-based regulatory capital ratios (CET1, Tier 1 capital and total capital) and for the leverage ratio. ​ The following table presents actual and required capital ratios as of December 31, 2020 and December 31, 2019 for the Company and the Bank under the current capital rules. Capital levels required to be considered well capitalized are based upon prompt corrective action regulations. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Required to be ​ ​ ​ ​ ​ ​ ​ Minimum Capital Considered Well ​ ​ Actual ​ Required - Basel III ​ Capitalized ​ (Dollars in thousands) Amount Ratio Capital Amount Ratio Capital Amount Ratio December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Common equity Tier 1 to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ $ 3,010,174 11.77 % $ 1,789,984 ​ 7.00 % $ 1,662,128 6.50 % South State Bank (the Bank) ​ 3,157,098 12.39 % 1,784,120 ​ 7.00 % 1,656,683 6.50 % Tier 1 capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 3,010,174 11.77 % 2,173,552 ​ 8.50 % 2,045,696 8.00 % South State Bank (the Bank) ​ 3,157,098 12.39 % 2,166,432 ​ 8.50 % 2,038,994 8.00 % Total capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 3,642,039 14.24 % 2,684,976 ​ 10.50 % 2,557,120 10.00 % South State Bank (the Bank) ​ 3,397,463 13.33 % 2,676,180 ​ 10.50 % 2,548,743 10.00 % Tier 1 capital to average assets (leverage ratio): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 3,010,174 8.27 % 1,455,135 ​ 4.00 % 1,818,919 5.00 % South State Bank (the Bank) ​ 3,157,098 8.71 % 1,450,600 ​ 4.00 % 1,813,250 5.00 % December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Common equity Tier 1 to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ $ 1,326,725 11.30 % $ 822,225 ​ 7.00 % $ 763,495 6.50 % South State Bank (the Bank) ​ 1,417,616 12.07 % 822,218 ​ 7.00 % 763,488 6.50 % Tier 1 capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 1,438,995 12.25 % 998,416 ​ 8.50 % 939,686 8.00 % South State Bank (the Bank) ​ 1,417,616 12.07 % 998,407 ​ 8.50 % 939,677 8.00 % Total capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 1,501,321 12.78 % 1,233,338 ​ 10.50 % 1,174,607 10.00 % South State Bank (the Bank) ​ 1,479,942 12.60 % 1,233,327 ​ 10.50 % 1,174,597 10.00 % Tier 1 capital to average assets (leverage ratio): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 1,438,995 9.73 % 591,731 ​ 4.00 % 739,664 5.00 % South State Bank (the Bank) ​ 1,417,616 9.59 % 591,592 ​ 4.00 % 739,490 5.00 % ​ As of December 31, 2020 and 2019, the capital ratios of the Company and the Bank were well in excess of the minimum regulatory requirements and exceeded the thresholds for the “well capitalized” regulatory classification. ​ In June 2016, the FASB issued ASU No. 2016-13 which required an entity to utilize a new impairment model known as the CECL model to estimate its lifetime “expected credit loss.” million. Instead of recognizing the effects on regulatory capital from ASU 2016-13 at adoption, the Company initially elected the option for recognizing the day 1 effects on the Company’s regulatory capital calculations over a three-year phase-in. In March 2020, in response to the COVID-19 pandemic, the regulatory agencies provided an additional transitional method option of a two-year deferral for the start of the three year phase-in of the recognition of the Day 1 effects of ASU 2016-13 along with an option to defer the current impact on regulatory capital calculations of ASU 2016-13 during the first two years (“5 year method”). Under this 5-year method, the Company would recognize an estimate of the previous incurred loss method for determining the allowance for credit losses in regulatory capital calculations and the difference from the CECL method would be deferred for two years. After two years, the effects from Day 1 and the deferral difference from the first two years of applying CECL would be phased-in over three years using the straight-line method. The Company chose the 5-year method and is deferring the recognition of the effects from Day 1 and the CECL difference from the first two years of application.

Condensed Financial Statements

Condensed Financial Statements of Parent Company	12 Months Ended
	Dec. 31, 2020
Condensed Financial Statements of Parent Company
Condensed Financial Statements of Parent Company	Note 28—Condensed Financial Statements of Parent Company ​ Financial information pertaining only to South State Corporation is as follows: Condensed Balance Sheets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ASSETS ​ ​ ​ Cash ​ $ 131,522 ​ $ 21,688 ​ Investment in subsidiaries ​ 4,802,993 ​ 2,467,466 ​ Other assets ​ 108,086 ​ 204 ​ Total assets ​ $ 5,042,601 ​ $ 2,482,982 ​ LIABILITIES AND SHAREHOLDERS’ EQUITY ​ ​ ​ ​ ​ ​ ​ Corporate and subordinated debentures ​ $ 390,179 ​ $ 115,833 ​ Other liabilities ​ ​ 4,542 ​ ​ 512 ​ Shareholders’ equity ​ 4,647,880 ​ 2,373,013 ​ Total liabilities and shareholders’ equity ​ $ 5,042,601 ​ $ 2,482,982 ​ ​ Condensed Statements of Income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Income: ​ ​ ​ ​ Dividends from subsidiary ​ $ 90,404 ​ $ 214,852 ​ $ 117,298 ​ Operating income ​ 52 ​ 5,386 ​ 67 ​ Total income ​ 90,456 ​ 220,238 ​ 117,365 ​ Operating expenses ​ 45,574 ​ 15,409 ​ 15,302 ​ Income before income tax benefit and equity in undistributed earnings of subsidiaries ​ 44,882 ​ 204,829 ​ 102,063 ​ Applicable income tax benefit ​ 8,960 ​ 1,883 ​ 3,055 ​ Equity in undistributed earnings of subsidiary (excess distribution) ​ 66,790 ​ (20,229) ​ 73,753 ​ Net income available to common shareholders ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 ​ ​ Condensed Statements of Cash Flows ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Cash flows from operating activities: ​ ​ ​ ​ Net income ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 ​ Adjustments to reconcile net income to net cash provided by operating activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ 1,528 ​ 666 ​ 666 ​ Share-based compensation ​ 23,316 ​ 8,839 ​ 8,783 ​ Gain on sale of securities available-for-sale ​ — ​ (5,366) ​ — ​ Decrease (increase) in other assets ​ (11,710) ​ (159) ​ 1,465 ​ Decrease in other liabilities ​ (12,323) ​ (959) ​ (2,048) ​ Undistributed earnings of subsidiary ​ (66,790) ​ 20,229 ​ (73,753) ​ Net cash provided by operating activities ​ 54,653 ​ 209,733 ​ 113,984 ​ Cash flows from investing activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Proceeds from sales and calls of other investment securities ​ ​ — ​ ​ 5,366 ​ ​ — ​ Repayment of investments in and advances to subsidiary ​ ​ 163,000 ​ ​ — ​ ​ — ​ Net cash inflow from acquisitions ​ 19,650 ​ — ​ — ​ Net cash provided by investing activities ​ 182,650 ​ 5,366 ​ — ​ Cash flows from financing activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Common stock issuance ​ 1,537 ​ 1,394 ​ 1,331 ​ Common stock repurchased ​ (32,431) ​ (159,431) ​ (70,577) ​ Dividends paid on common stock ​ (98,256) ​ (57,696) ​ (50,557) ​ Stock options exercised ​ 1,681 ​ 1,230 ​ 1,032 ​ Net cash used in financing activities ​ (127,469) ​ (214,503) ​ (118,771) ​ Net increase (decrease) in cash and cash equivalents ​ 109,834 ​ 596 ​ (4,787) ​ Cash and cash equivalents at beginning of period ​ 21,688 ​ 21,092 ​ 25,879 ​ Cash and cash equivalents at end of period ​ $ 131,522 ​ $ 21,688 ​ $ 21,092 ​ ​

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2020
Derivative Financial Instruments
Derivative Financial Instruments	Note 29—Derivative Financial Instruments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ December 31, 2019 ​ ​ Balance Sheet ​ Notional ​ Estimated Fair Value ​ Notional ​ Estimated Fair Value (Dollars in thousands) Location Amount Gain Loss Amount Gain Loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash flow hedges of interest rate risk on FHLB Advances: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pay fixed rate swap with counterparty ​ Other Liabilities ​ $ — ​ $ — ​ $ — ​ $ 700,000 ​ $ — ​ $ 13,791 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value hedge of interest rate risk: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pay fixed rate swap with counterparty ​ Other Assets and Other Liabilities ​ $ 16,439 ​ $ — ​ $ 2,086 ​ $ 2,754 ​ $ — ​ $ 199 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Not designated hedges of interest rate risk: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Customer related interest rate contracts: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Matched interest rate swaps with borrowers ​ Other Assets and Other Liabilities ​ $ 9,324,359 ​ $ 802,717 ​ $ 46 ​ $ 564,068 ​ $ 15,277 ​ $ 1,019 Matched interest rate swaps with counterparty ​ Other Assets and Other Liabilities ​ $ 9,324,359 ​ $ 46 ​ $ 802,700 ​ $ 564,068 ​ $ 73 ​ $ 15,475 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Not designated hedges of interest rate risk - mortgage banking activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contracts used to hedge mortgage servicing rights ​ Other Assets and Other Liabilities ​ $ 149,000 ​ $ 119 ​ $ — ​ $ 133,000 ​ $ — ​ $ 789 Contracts used to hedge mortgage pipeline ​ Other Assets ​ $ 528,500 ​ $ 11,017 ​ $ — ​ $ 87,773 ​ $ 902 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total derivatives ​ ​ ​ $ 19,342,657 ​ $ 813,899 ​ $ 804,832 ​ $ 2,051,663 ​ $ 16,252 ​ $ 31,273 ​ Cash Flow Hedges of Interest Rate Risk The Company is exposed to interest rate risk in the course of its business operations and manages a portion of this risk through the use of derivative financial instruments, in the form of interest rate swaps. The Company accounts for its interest rate swap that is classified as a cash flow hedge in accordance with FASB ASC 815, Derivatives and Hedging , which requires that all derivatives be recognized as assets or liabilities on the balance sheet at fair value. For more information regarding the fair value of the Company’s derivative financial instruments, see Note 26 — During 2020 and 2019, the Company utilized interest rate swap agreements to manage interest rate risk related to funding through short term FHLB advances. In March 2019, we entered into three-month FHLB advances for $350 million and $150 million which were continuously renewed. At the same time, we entered into interest rate swap agreements with a notional amount of $350 million and $150 million to manage the interest rate risk related to these FHLB advances. In June 2019, we entered into a three-month FHLB advance for $200 million which was continuously renewed. At the same time, we entered into an interest rate swap agreement with a notional amount of $200 million to manage the interest rate risk related to this FHLB advance. With our plan to continually renew and reprice the FHLB advances every three months, we were treating this funding as variable rate funding and hedging the cash flows from these FHLB advances against future interest rate increases by using an interest rate swap that effectively fixed the rate on the debt. The notional amount on which the interest payments were based was not exchanged related to these interest rate swaps. During the fourth quarter of 2020, the Company made the decision to repay the FHLB advances and terminate the interest rate swap agreements due to the current low interest rate environment and the expectation that interest rates will remain low during the average life of these interest rate swaps. As a result, in December 2020, the Company recorded through earnings termination costs of $40.8 million related to the interest rate swaps which included $2.0 million in interest expense on the interest rate swap hedges. For derivatives designated as hedging exposure to variable cash flows of a forecasted transaction (cash flow hedge), the derivative’s entire gain or loss is initially reported as a component of other comprehensive income and subsequently reclassified into earnings when the forecasted transaction affects earnings or when the hedge is terminated. For derivatives that are not designated as hedging instruments, changes in the fair value of the derivatives are recognized in earnings immediately. For designated hedging relationships, we have a third party perform retrospective and prospective effectiveness testing on a quarterly basis using quantitative methods to determine if the hedge is still highly effective. Hedge accounting ceases on transactions that are no longer deemed highly effective, or for which the derivative has been terminated or de-designated. The Company recognized an after-tax unrealized gain on its cash flow hedges in other comprehensive income for the year ended December 31, 2020 of $10.8 million, compared to a $10.7 million loss for the year ended December 31, 2019. During 2020, at the time of the termination of the cash flow hedges, the Company reclassified into current earnings the unrealized loss on the cash flow hedge of $38.8 million ($30.3 million after-tax). The Company did not maintain any cash flow hedges on the balance sheet at December 31, 2020. The Company maintained a $13.8 million cash flow hedge liability for the year ended December 31, 2019. There was no ineffectiveness in the cash flow hedges during the years ended December 31, 2020 and 2019. (See Note 16 — Credit risk related to the derivative arises when amounts receivable from the counterparty (derivatives dealer) exceed those payable. We control the risk of loss by only transacting with derivatives dealers that are national market makers whose credit ratings are strong. Each party to the interest rate swap is required to provide collateral in the form of cash or securities to the counterparty when the counterparty’s exposure to a mark-to-market replacement value exceeds certain negotiated limits. These limits are typically based on current credit ratings and vary with ratings changes. At December 31, 2020, there was no collateral pledged for cash flow hedges with the hedges being terminated in the fourth quarter of 2020. At December 31, 2019, collateral on the cash flow hedges on the FHLB advances was included in cash and cash equivalents on the balance sheet as deposits in other financial institutions (restricted cash). Also, we have a netting agreement with the counterparties. Balance Sheet Fair Value Hedge ​ As of December 31, 2020 and 2019, the Company maintained loan swaps, with an aggregate notional amount of $16.4 million and $2.8 million, respectively, accounted for as a fair value hedge in accordance with ASC 815, Derivatives and Hedgin g. This derivative protects the company from interest rate risk caused by changes in the LIBOR curve in relation to a certain designated fixed rate loan. The derivative converts the fixed rate loan to a floating rate. Settlement occurs in any given period where there is a difference in the stated fixed rate and variable rate. The fair value of this hedge is recorded in other assets or in other liabilities. All changes in fair value are recorded through earnings as noninterest income. There was Non-designated Hedges of Interest Rate Risk ​ Customer Swaps ​ The Company maintains interest rate swap contracts with customers that are classified as non-designated hedges and are not speculative in nature. These agreements are designed to convert customer’s variable rate loans with the Company to fixed rate. These interest rate swaps are executed with loan customers to facilitate a respective risk management strategy and allow the customer to pay a fixed rate of interest to the Company. These interest rate swaps are simultaneously hedged by executing offsetting interest rate swaps with unrelated market counterparties to minimize the net risk exposure to the Company resulting from the transactions and allow the Company to receive a variable rate of interest. The interest rate swaps pay and receive interest based on a floating rate based on one month LIBOR plus credit spread, with payments being calculated on the notional amount. The interest rate swaps are settled monthly with varying maturities. ​ As the interest rate swaps associated with this program do not meet the strict hedge accounting requirements, changes in the fair value of both the customer swaps and the offsetting swaps are recognized directly in earnings. As of December 31, 2020 and 2019, the interest rate swaps had an aggregate notional amount of approximately billion, respectively. At December 31, 2020, the fair value of the interest rate swap derivatives was recorded in other assets at million. All changes in fair value are recorded through earnings as noninterest income. As of December 31, 2020, we provided $663.5 million of cash collateral on the counterparty swaps which is included in cash and cash equivalents on the balance sheet as deposits in other financial institutions (restricted cash). The Company also provided $554.7 million in investment securities at market value as collateral on the counterparty swaps which is included in investment securities – available-for-sale. ​ Foreign Exchange ​ The Company also enters into foreign exchange contracts with customers to accommodate their need to convert certain foreign currencies into U.S. Dollars. To offset the foreign exchange risk, the Company has entered into substantially identical agreements with an unrelated market counterparty to hedge these foreign exchange contracts. At December 31, 2020 and 2019, there were no outstanding contracts or agreements related to foreign currency. If there were foreign currency contracts outstanding at December 31, 2020 and 2019, the fair value of these contracts would be included in other assets and other liabilities in the accompanying balance sheet. All changes in fair value are recorded as other noninterest income. There was no gain or loss recorded related to the foreign exchange derivative for the years ended December 31, 2020 or 2019. Mortgage Banking The Company also has derivatives contracts that are not classified as accounting hedges to mitigate risks related to its mortgage banking activities. These instruments may include financial forwards, futures contracts, and options written and purchased, which are used to hedge mortgage servicing rights; while forward sales commitments are typically used to hedge the mortgage pipeline. Such instruments derive their cash flows, and therefore their values, by reference to an underlying instrument, index or referenced interest rate. The Company does not elect hedge accounting treatment for any of these derivative instruments and as a result, changes in fair value of the instruments (both gains and losses) are recorded in the Company’s consolidated statements of income in mortgage banking income. Mortgage Servicing Rights Derivatives contracts related to mortgage servicing rights are used to help offset changes in fair value and are written in amounts referred to as notional amounts. Notional amounts provide a basis for calculating payments between counterparties but do not represent amounts to be exchanged between the parties, and are not a measure of financial risk. On December 31, 2020 and 2019, the Company had derivative financial instruments outstanding with notional amounts totaling $149.0 million and $133.0 million related to mortgage servicing rights, respectively. The estimated net fair value of the open contracts related to the mortgage servicing rights was recorded as a gain of $119,000 at December 31, 2020 compared to a loss of The following table presents the Company’s notional value of forward sale commitments and the fair value of those obligations along with the fair value of the mortgage loan pipeline. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2020 2019 Mortgage loan pipeline ​ ​ $ 510,730 ​ $ 80,785 Expected closures ​ ​ 411,273 ​ 60,588 Fair value of mortgage loan pipeline commitments ​ ​ 15,328 ​ 1,160 Forward sales commitments ​ ​ 528,500 ​ 87,773 Fair value of forward commitments ​ ​ (4,311) ​ (258) ​

Loan Servicing, Mortgage Origin

Loan Servicing, Mortgage Origination, and Loans Held for Sale	12 Months Ended
	Dec. 31, 2020
Loan Servicing, Mortgage Origination, and Loans Held for Sale
Loan Servicing, Mortgage Origination, and Loans Held for Sale	Note 30—Loan Servicing, Mortgage Origination, and Loans Held for Sale The portfolio of residential mortgages serviced for others, which are not included in the accompanying balance sheets, was $5.1 billion and $3.3 billion at December 31, 2020 and 2019, respectively. Servicing loans for others generally consists of collecting mortgage payments, maintaining escrow accounts and disbursing payments to investors. The amounts of contractually specified servicing fees earned by the Company during the years ended December 31, 2020 and 2019 were $9.8 million and $7.8 million, respectively. Servicing fees are recorded in mortgage banking income in the Company’s consolidated statements of income. At December 31, 2020 and 2019, MSRs were $43.8 million and $30.5 million, respectively, on the Company’s consolidated balance sheet. MSRs are recorded at fair value with changes in fair value recorded as a component of mortgage banking income in the Consolidated Statements of Income. The market value adjustments related to MSRs recorded in mortgage banking income for the years ended December 31, 2020 and 2019 were a loss of $7.4 million and a loss of $7.0 million, respectively. The Company has used various free standing derivative instruments to mitigate the income statement effect of changes in fair value due to changes in market value adjustments and to changes in valuation inputs and assumptions related to MSRs. The following table presents the changes in the fair value of MSRs and its offsetting hedge. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Increase (decrease) in fair value of MSRs ​ ​ $ (7,421) ​ $ (6,976) ​ $ 1,861 ​ Decay of MSRs ​ ​ (8,793) ​ (4,589) ​ (4,215) ​ Gain related to derivatives ​ ​ 10,177 ​ 3,967 ​ (953) ​ Net effect on statements of income ​ ​ $ (6,037) ​ $ (7,598) ​ $ (3,307) ​ ​ The fair value of MSRs is highly sensitive to changes in assumptions and fair value is determined by estimating the present value of the asset’s future cash flows utilizing market- based prepayment rates, discount rates and other assumptions validated through comparison to trade information, industry surveys and with the use of independent third party appraisals. Changes in prepayment speed assumptions have the most significant impact on the fair value of MSRs. Generally, as interest rates decline, mortgage loan prepayments accelerate due to increased refinance activity, which results in a decrease in the fair value of the MSR. Measurement of fair value is limited to the conditions existing and the assumptions utilized as of a particular point in time, and those assumptions may not be appropriate if they are applied at a different time. See Note 26 — The characteristics and sensitivity analysis of the MSRs are included in the following table. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2020 2019 Composition of residential loans serviced for others ​ ​ ​ ​ ​ ​ ​ Fixed-rate mortgage loans ​ ​ 99.9 % ​ 99.8 % Adjustable-rate mortgage loans ​ ​ 0.1 % ​ 0.2 % Total ​ ​ 100.0 % ​ 100.0 % Weighted average life ​ ​ 6.10 years ​ 6.55 years Constant Prepayment rate (CPR) ​ ​ 12.3 % ​ 10.3 % Weighted average discount rate ​ ​ 9.0 % ​ 9.4 % Effect on fair value due to change in interest rates ​ ​ ​ ​ ​ ​ ​ 25 basis point increase ​ $ 2,744 ​ $ 2,477 ​ 50 basis point increase ​ ​ 5,520 ​ 4,452 ​ 25 basis point decrease ​ ​ (2,497) ​ (2,938) ​ 50 basis point decrease ​ ​ (4,114) ​ (6,228) ​ ​ The sensitivity calculations above are hypothetical and should not be considered to be predictive of future performance. Changes in fair value based on adverse changes in assumptions generally cannot be extrapolated because the relationship of the changes in assumptions to fair value may not be linear. Also, in this table, the effects of an adverse variation in a particular assumption on the fair value of the MSRs is calculated without changing any other assumptions, while in reality, changes in one factor may result in changing another, which may magnify or contract the effect of the change. Custodial escrow balances maintained in connection with the loan servicing were $26.6 million and $16.5 million at December 31, 2020 and 2019. Whole loan sales were $3.2 billion and $812.3 million for the years ended December 31, 2020 and 2019, of which $2.7 billion and $660.6 million or 85.1% and 81.3% were sold with the servicing rights retained by the Company. Loans held for sale have historically been comprised of residential mortgage loans awaiting sale in the secondary market, which generally settle in 15 to 45 days. At December 31, 2020, loans held for sale were $290.5 million, compared with $59.4 million at December 31, 2019.

Investments in Qualified Afford

Investments in Qualified Affordable Housing Projects	12 Months Ended
	Dec. 31, 2020
Investments in Qualified Affordable Housing Projects
Investments in Qualified Affordable Housing Projects	Note 31—Investments in Qualified Affordable Housing Projects The Company has investments in qualified affordable housing projects (“QAHPs”) that provide low income housing tax credits and operating loss benefits over an extended period. The tax credits and the operating loss tax benefits that are generated by each of the properties are expected to exceed the total value of the investment made by the Company. For the year ended December 31, 2020, tax credits and other tax benefits of $11.2 million and amortization of $12.9 million were recorded. For the year ended December 31, 2019, the Company recorded tax credits and other tax benefits of $5.9 million and amortization of $6.0 million. At December 31, 2020 and 2019, the Company’s carrying value of QAHPs was $105.6 million and $76.9 million, respectively, with an original investment of $137.1 million. The Company has $42.7 million and $35.7 million in remaining funding obligations related to these QAHPs recorded in liabilities at December 31, 2020 and 2019, respectively. None of the original investment will be repaid. The investment in QAHPs is being accounted for using the equity method. ​

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events
Subsequent Events	Note 32—Subsequent Events On January 27, 2021, the Company’s Board of Directors approved the authorization of a new 3.5 million share Company stock repurchase plan (the “New Repurchase Program”). The New Repurchase Plan replaces the Company’s prior stock repurchase plan announced on June 13, 2019 in its entirety. The repurchases under the New Repurchase Program will be made from time to time by the Company in the open market as conditions allow and the repurchase plan has made available for , unless shortened or extended by the Company’s Board of Directors. The stock repurchase program does not obligate the Company to repurchase any specified number of shares of its common stock. The shares may be purchased in open market or negotiated transactions, block trades, accelerated share repurchase transactions or pursuant to one or more trading plans established pursuant to Rule 10b5-1. Open market purchases will be conducted in accordance with the limitations set forth in Rule 10b-18 of the Securities and Exchange and Commission and other applicable legal requirements. The number, price and timing of the repurchases, if any, will be at the Company’s sole discretion and will depend on a number of factors, including market and economic conditions, liquidity needs and other factors and there is no assurance that the Company will purchase any shares under the program. ​ serving primarily institutional clients across the U.S. in the fixed income business. Duncan-Williams firm became an operating subsidiary of South State Bank immediately following the transaction. The transaction provides the Company with a seasoned team of revenue producers as well as an expanded platform through which the Correspondent Banking Division can leverage additional opportunities. The transaction represents an attractive capital deployment opportunity for the company and the ability to grow its fee-based businesses.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Summary of Significant Accounting Policies
Nature of operations	Nature of Operations South State Corporation (the “Company”) is a financial holding company whose principal activity is the ownership and management of its wholly owned subsidiary, South State Bank, National Association (the “Bank”). The Bank operates South State Advisory, Inc. (formerly First Southeast 401k Fiduciaries, Inc.), a wholly-owned registered investment advisor. We merged Minis & Co., Inc., another registered investment advisor that was wholly-owned by the Bank, with and into South State Advisory, Inc. effective January 1, 2019. We will continue to use the name Minis & Company as a Doing Business As (DBA) going forward. Through the merger with CenterState Bank Corporation (“CSFL”) in the second quarter of 2020, the Bank also owns CBI Holding Company, LLC (“CBI”), which in turn owns Corporate Billing, LLC (“Corporate Billing”), a transaction-based finance company headquartered in Decatur, Alabama that provides factoring, invoicing, collection and accounts receivable management services to transportation companies and automotive parts and service providers nationwide. Also, through the merger with CSFL in the second quarter of 2020, the holding company operates R4ALL, Inc., which manages a troubled loan purchased from the Bank to its eventual disposition and SSB Insurance Corp., a captive insurance subsidiary pursuant to Section 831(b) of the U.S. Tax Code. The Company also operates a correspondent banking division within the national bank subsidiary, of which the majority of its bond salesmen, traders and operational personnel are housed in facilities located in Birmingham, Alabama and Atlanta, Georgia. The Bank provides general banking services within 28 counties in South Carolina, 32 counties in Florida, 9 counties in North Carolina, 25 counties in Georgia, 5 counties in Alabama, and 4 counties in Virginia. The accounting and reporting policies of the Company and its consolidated subsidiary conform to accounting principles generally accepted in the United States of America (‘U.S. GAAP”). There are 20 unconsolidated subsidiaries of the Company that were established for the purpose of issuing in the aggregate of approximately $153.5 million of trust preferred securities. See Note 12—Other Borrowings for further detailed descriptions of our trust preferred securities. Unless otherwise mentioned or unless the context requires otherwise, references herein to "South State," the "Company" "we," "us," "our" or similar references mean South State Corporation and its consolidated subsidiaries. References to the “Bank” means South State Bank, National Association.
Basis of Consolidation	Basis of Consolidation The consolidated financial statements include the accounts of the Company and other entities in which it has a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation. Assets held by the Company in trust are not assets of the Company and are not included in the accompanying consolidated financial statements.
Segments	Segments The Company, through its Bank subsidiary, provides a broad range of financial services to individuals and companies in South Carolina, North Carolina, Florida, Alabama, Georgia and Virginia. These services include demand, time and savings deposits; lending and credit card servicing; ATM processing; mortgage banking services; correspondent banking services and wealth management and trust services. While the Company’s decision makers monitor the revenue streams of the various financial products and services, operations are managed and financial performance is evaluated on an organization- wide basis. Accordingly, the Company’s banking and finance operations are not considered by management to constitute more than one reportable operating segment.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the consolidated balance sheet and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term relate to the determination of the allowance for credit losses for loans and investment securities held-to-maturity, fair value of financial instruments, fair values of assets and liabilities acquired in business combinations, loss estimates related to loans and other real estate acquired, evaluating impairment of investment securities, goodwill impairment tests and valuation of deferred tax assets. In connection with the determination of the allowance for credit losses, management has identified specific loans as well as adopted a policy of providing amounts for loan valuation purposes which are not identified with any specific loan but are derived from models based on macroeconomic factors and forecasts. Management believes that the allowance for credit losses is adequate. While management uses available information to recognize losses on loans, future additions to the allowance may be necessary based on changes in economic forecasts. In addition, regulatory agencies, as an integral part of the examination process, periodically review the banking subsidiary’s allowance for credit losses. Such agencies may require additions to the allowance based on their judgments about information available to them at the time of their examination.
Concentrations of Credit Risk	Concentrations of Credit Risk The Company’s Bank subsidiary grants agribusiness, commercial, and residential loans to customers throughout South Carolina, North Carolina, Florida, Alabama, Virginia and Georgia. Although the subsidiary has a diversified loan portfolio, a substantial portion of their borrowers’ abilities to honor their contracts is dependent upon economic conditions within South Carolina, North Carolina, Florida, Alabama, Virginia, Georgia and the surrounding regions. The Company considers concentrations of credit to exist when, pursuant to regulatory guidelines, the amounts loaned to a multiple number of borrowers engaged in similar business activities which would cause them to be similarly impacted by general economic conditions represents 25% of total Tier 1 capital plus regulatory adjusted allowance for credit losses of the Company, or $841.1 million at December 31, 2020. Based on this criteria, the Company had five such credit concentrations at December 31, 2020, including loans on hotels and motels of $969.9 million, loans to lessors of nonresidential buildings (except mini-warehouses) of $3.7 billion, loans secured by owner occupied nonresidential buildings of $3.1 billion, loans to lessors of residential buildings (investment properties and multi-family) of $1.1 billion and loans secured by 1 st
Cash and Cash Equivalents	Cash and Cash Equivalents For the purpose of presentation in the consolidated statements of cash flows, cash and cash equivalents include cash on hand, cash items in process of collection, amounts due from banks including restricted pledged cash, interest bearing deposits with banks, purchases of securities under agreements to resell, and federal funds sold. Due from bank balances are maintained at other financial institutions. Federal funds sold are generally purchased and sold for one-day periods, but may, from time to time, have longer terms. The Company enters from time to time into purchases of securities under agreements to resell substantially identical securities. When the Company enters into such repurchase agreements, the securities purchased under agreements to resell generally consist of U.S. government-sponsored entities and agency mortgage-backed securities. The Company may elect to use other asset classes at its discretion. It is the Company’s practice to take possession of securities purchased under agreements to resell. The securities are delivered into the Company’s account maintained by a third- party custodian designated by the Company under a written custodial agreement that explicitly recognizes the Company’s interest in the securities. The Company monitors the market value of the underlying securities, including accrued interest, which collateralizes the related receivable on agreements to resell. Historically, these agreements were considered to be cash equivalents with maturities of three months or less. The Company held no securities under agreements to resell at December 31, 2020.
Trading Securities	Trading Securities The Company has a trading securities portfolio where t For this portfolio, interest income is included in the net interest margin and realized and unrealized gains and losses are included in correspondent banking and capital market income, a component of Non-interest Income in our “Consolidated Statements of Income.” Securities purchased for this portfolio have primarily been municipal securities and are held for short periods of time.
Investment Securities	Investment Securities Debt securities that management has the positive intent and ability to hold to maturity are classified as “held-to-maturity” and carried at amortized cost. Securities not classified as held-to-maturity, including equity securities with readily determinable fair values, are classified as “available-for-sale” and carried at fair value with unrealized gains and losses excluded from earnings and reported in other comprehensive income. Purchase premiums and discounts are recognized in interest income using methods approximating the interest method over the terms of the securities. Gains and losses realized on sales of securities available-for-sale are determined using the specific identification method. Management no longer evaluates securities for other-than-temporary impairment, otherwise referred to herein as OTTI, as ASC Subtopic 326-30, Financial Instruments—Credit Losses—Available-for-Sale Debt Securities, changes the accounting for recognizing impairment on available-for-sale debt securities. Each quarter Management evaluates impairment where there has been a decline in fair value below the amortized cost basis of a security to determine whether there is a credit loss associated with the decline in fair value. Management considers the nature of the collateral, potential future changes in collateral values, default rates, delinquency rates, third-party guarantees, credit ratings, interest rate changes since purchase, volatility of the security’s fair value and historical loss information for financial assets secured with similar collateral among other factors. Credit losses are calculated individually, rather than collectively, using a discounted cash flow method, whereby Management compares the present value of expected cash flows with the amortized cost basis of the security. The credit loss component would be recognized through the provision for credit losses in the Statements of Income. (see Note 4—Investment Securities). Other investments include stock acquired for regulatory purposes, investments in unconsolidated subsidiaries and other nonmarketable investment securities. Stock acquired for regulatory purposes include Federal Home Loan Bank of Atlanta (“FHLB”) stock and Federal Reserve Bank (“FRB”) stock. These securities do not have a readily determinable fair value because their ownership is restricted and they lack a market for trading. As a result, these securities are carried at cost and are periodically evaluated for impairment. Investments in unconsolidated subsidiaries represent a minority investment in SCBT Capital Trust I, SCBT Capital Trust II, SCBT Capital Trust III, TSB Statutory Trust I, SAVB Capital Trust I, SAVB Capital Trust II, Southeastern Bank Financial Statutory Trust I, Southeastern Bank Financial Statutory Trust II, Provident Community Bancshares Capital Trust I, FCRV Statutory Trust I, Community Capital Statutory Trust I, CSBC Statutory Trust I, Provident Community Bancshares Capital Trust II, CenterState Banks of Florida Statutory Trust I, Valrico Capital Statutory Trust, Federal Trust Statutory Trust I, Gulfstream Bancshares Capital Trust II, Homestead Statutory Trust I, BSA Financial Statutory Trust I and MRCB Statutory Trust II. These investments are recorded at cost and the Company receives quarterly dividend payments on these investments. Other nonmarketable investment securities consist of Business Development Corporation stock and stock in Banker’s Banks. These investments also do not have a readily determinable fair value because their ownership is restricted and they lack a market for trading. As a result, these securities are carried at cost and are periodically evaluated for impairment.
Loans Held for Sale	Loans Held for Sale Loans originated and intended for sale are carried at the estimated fair value in the aggregate. Estimated fair value is determined on the basis of existing forward commitments, or the current market value of similar loans. Net unrealized losses, if any, are recognized through a valuation allowance by charges to income. Loans held-for-sale are sold to investors either under guaranteed delivery or with the best effort intent and ability to sell loans as long as they meet the underwriting standards of the potential investor.
Loans	Loans Loans that management has originated and has the intent and ability to hold for the foreseeable future or until maturity or pay off generally are reported at their unpaid principal balances, less unearned income and net of any deferred loan fees and costs. Unearned income on installment loans is recognized as income over the terms of the loans by methods that generally approximate the interest method. Interest on other loans is calculated by using the simple interest method on daily balances of the principal amount outstanding. We place non acquired loans and acquired loans on nonaccrual once reasonable doubt exists about the collectability of all principal and interest due. Generally, this occurs when principal or interest is 90 days or more past due, unless the loan is well secured and in the process of collection. A loan is evaluated individually for loss when it is on nonaccrual and has a net book balance over $1 million. Large pools of homogeneous loans are collectively evaluated for loss and given a general reserve. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as nonaccrual, provided that management expects to collect all amounts due, including interest accrued at the contractual interest rate for the period of delay.
Troubled Debt Restructurings ("TDRs")	Troubled Debt Restructurings (“TDRs”) The Bank measures expected credit losses over the contractual term of a loan. When determining the contractual term, the Company considers expected prepayments but is precluded from considering expected extensions, renewals, or modifications, unless the Company reasonably expects it will execute a troubled debt restructuring (“TDR”) with a borrower. In the event of a reasonably-expected TDR, the Company factors the reasonably-expected TDR into the current expected credit losses estimate. For consumer loans, the point at which a TDR is reasonably expected is when the Company approves the borrower’s application for a modification (i.e., the borrower qualifies for the TDR) or when the Credit Administration department approves loan concessions on substandard loans. For commercial loans, the point at which a TDR is reasonably expected is when the Company approves the loan for modification or when the Credit Administration department approves loan concessions on substandard loans. The Company uses a discounted cash flow methodology for a TDR to calculate the effect of the concession provided to the borrower within the ACL. A restructuring that results in only a delay in payments that is insignificant is not considered an economic concession. In accordance with the Coronavirus Aid, Relief, and Economic Security Act, also known as the CARES Act, the Company implemented loan modification programs in response to the COVID-19 pandemic in order to provide borrowers with flexibility with respect to repayment terms. The Company’s payment relief assistance includes forbearance, deferrals, extension and re-aging programs, along with certain other modification strategies. The Company elected the accounting policy in the CARES Act to not apply TDR accounting to loans modified for borrowers impacted by the COVID-19 pandemic if the concession meets the criteria as defined under the CARES Act.
Allowance for Credit Losses ("ACL")	Allowance for Credit Losses (“ACL”) On January 1, 2020, we adopted the requirements of Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, sometimes referred to herein as ASU 2016-13. Topic 326 was subsequently amended by ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments-Credit Losses; ASU No. 2019-05, Codification Improvements to Topic 326, Financial Instruments-Credit Losses; and ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments. This standard applies to all financial assets measured at amortized cost and off balance sheet credit exposures, including loans, investment securities and unfunded commitments. We applied the standard’s provisions using the modified retrospective method as a cumulative-effect adjustment to retained earnings as of January 1, 2020. With this transition method, we did not have to restate comparative prior periods presented in the financial statements related to Topic 326, but will present comparative prior periods disclosures using the previous accounting guidance for the allowance for loan losses. This adoption method is considered a change in accounting principle requiring additional disclosure of the nature of and reason for the change, which is solely a result of the adoption of the required standard. ACL – Investment Securities Management uses a systematic methodology to determine its ACL for investment securities held-to-maturity. The ACL is a valuation account that is deducted from the amortized cost basis to present the net amount expected to be collected on the held-to-maturity portfolio. Management considers the effects of past events, current conditions, and reasonable and supportable forecasts on the collectability of the portfolio. The Company’s estimate of its ACL involves a high degree of judgment; therefore, Management’s process for determining expected credit losses may result in a range of expected credit losses. Management monitors the held-to-maturity portfolio to determine whether a valuation account would need to be recorded. As of December 31, 2020, the Company had $955.5 million of held-to-maturity securities and no related valuation account. Management no longer evaluates available-for-sale securities for other-than-temporary impairment, otherwise referred to herein as OTTI, as ASC Subtopic 326-30, Financial Instruments—Credit Losses—Available-for-Sale Debt Securities, changes the accounting for recognizing impairment on available-for-sale debt securities. Each quarter Management evaluates impairment where there has been a decline in fair value below the amortized cost basis of an available-for-sale security to determine whether there is a credit loss associated with the decline in fair value. Management considers the nature of the collateral, potential future changes in collateral values, default rates, delinquency rates, third-party guarantees, credit ratings, interest rate changes since purchase, volatility of the security’s fair value and historical loss information for financial assets secured with similar collateral among other factors. Credit losses are calculated individually, rather than collectively, using a discounted cash flow method, whereby Management compares the present value of expected cash flows with the amortized cost basis of the security. The credit loss component would be recognized through the provision for credit losses in the Statements of Income. Management excludes the accrued interest receivable balance from the amortized cost basis in measuring expected credit losses on the investment securities and does not record an allowance for credit losses on accrued interest receivable. As of December 31 2020, the accrued interest receivable for investment securities available-for-sale recorded in Other Assets was $13.1 million. ACL - Loans The ACL reflects Management’s estimate of losses that will result from the inability of our borrowers to make required loan payments. The Company established the incremental increase in the ACL at adoption through equity and subsequent adjustments through a provision for credit losses charged to earnings. The Company records loans charged off against the ACL and subsequent recoveries, if any, increase the ACL when they are recognized. Management uses systematic methodologies to determine its ACL for loans held for investment and certain off-balance-sheet credit exposures. The ACL is a valuation account that is deducted from the amortized cost basis to present the net amount expected to be collected on the loan portfolio. Management considers the effects of past events, current conditions, and reasonable and supportable forecasts on the collectability of the loan portfolio. The Company’s estimate of its ACL involves a high degree of judgment; therefore, Management’s process for determining expected credit losses may result in a range of expected credit losses. The Company’s ACL recorded in the balance sheet reflects Management’s best estimate within the range of expected credit losses. The Company recognizes in net income the amount needed to adjust the ACL for Management’s current estimate of expected credit losses. The Company’s ACL is calculated using collectively evaluated and individually evaluated loans. The Company merged with CSFL on June 7, 2020. For the second quarter ended June 30, 2020, given the proximity of the merger date to the quarter end, Management evaluated loans from each legacy loan portfolio utilizing pre-existing methodologies implemented prior to the merger and aggregated the result. During the third quarter, Management consolidated the two methodologies into one to arrive at the ACL recorded at December 31, 2020. The allowance for credit losses is measured on a collective pool basis when similar risk characteristics exist. Loans with similar risk characteristics are grouped into homogenous segments, or pools, for analysis. The Discounted Cash Flow (“DCF”) method is utilized for each loan in a pool, and the results are aggregated at the pool level. A periodic tendency to default and absolute loss given default are applied to a projective model of the loan’s cash flow while considering prepayment and principal curtailment effects. The analysis produces expected cash flows for each instrument in the pool by pairing loan-level term information (e.g., maturity date, payment amount, interest rate, etc.) with top-down pool assumptions (e.g., default rates and prepayment speeds). The Company has identified the following portfolio segments: Owner-Occupied Commercial Real Estate, Non Owner-Occupied Commercial Real Estate, Multifamily, Municipal, Commercial and Industrial, Commercial Construction and Land Development, Residential Construction, Residential Senior Mortgage, Residential Junior Mortgage, Revolving Mortgage, and Consumer and Other. In determining the proper level of the ACL, Management has determined that the loss experience of the Bank provides the best basis for its assessment of expected credit losses. It therefore utilized its own historical credit loss experience by each loan segment over an economic cycle, while excluding loss experience from certain acquired institutions (i.e., failed banks). For most of the segment models for collectively evaluated loans, the Company incorporated two or more macroeconomic drivers using a statistical regression modeling methodology. Management considers forward-looking information in estimating expected credit losses. The Company subscribes to a third-party service which provides a quarterly macroeconomic baseline outlook and alternative scenarios for the United States economy. The baseline, along with the evaluation of alternative scenarios, is used by Management to determine the best estimate within the range of expected credit losses. The baseline forecast incorporates a 50% probability of the United States economy performing better than this projection and the same as the probability that it will perform worse. Management has evaluated the appropriateness of the reasonable and supportable forecast scenarios and has made adjustments as needed. For the contractual term that extends beyond the reasonable and supportable forecast period, the Company reverts to the long term mean of historical factors within four quarters using a straight-line approach. The Company generally utilizes a four-quarter forecast and a four-quarter reversion period. Included in its systematic methodology to determine its ACL, Management considers the need to qualitatively adjust expected credit losses for information not already captured in the loss estimation process. These qualitative adjustments either increase or decrease the quantitative model estimation (i.e., formulaic model results). Each period the Company considers qualitative factors that are relevant within the qualitative framework that includes the following: 1) Lending Policy; 2) Economic conditions not captured in models; 3) Volume and Mix of Loan Portfolio; 4) Past Due Trends; 5) Concentration Risk; 6) External Factors; and 7) Model Limitations. When a loan no longer shares similar risk characteristics with its segment, the asset is assessed to determine whether it should be included in another pool or should be individually evaluated. The Company consolidated the ACL models and due to the size of the combined company, elected to increase the threshold for individually-evaluated loans to all non-accrual loans with a net book balance in excess of $1.0 million. Management will monitor the credit environment and make adjustments to this threshold in the future if warranted. Based on the threshold above, consumer financial assets will generally remain in pools unless they meet the dollar threshold. The expected credit losses on individually-evaluated loans will be estimated based on discounted cash flow analysis unless the loan meets the criteria for use of the fair value of collateral, either by virtue of an expected foreclosure or through meeting the definition of collateral-dependent. Financial assets that have been individually evaluated can be returned to a pool for purposes of estimating the expected credit loss insofar as their credit profile improves and that the repayment terms were not considered to be unique to the asset. Management measures expected credit losses over the contractual term of a loan. When determining the contractual term, the Company considers expected prepayments but is precluded from considering expected extensions, renewals, or modifications, unless the Company reasonably expects it will execute a troubled debt restructuring (“TDR”) with a borrower. In the event of a reasonably-expected TDR, the Company factors the reasonably-expected TDR into the current expected credit losses estimate. For consumer loans, the point at which a TDR is reasonably expected is when the Company approves the borrower’s application for a modification (i.e., the borrower qualifies for the TDR) or when the Credit Administration department approves loan concessions on substandard loans. For commercial loans, the point at which a TDR is reasonably expected is when the Company approves the loan for modification or when the Credit Administration department approves loan concessions on substandard loans. The Company uses a discounted cash flow methodology for a TDR to calculate the effect of the concession provided to the borrower within the ACL. A restructuring that results in only a delay in payments that is insignificant is not considered an economic concession. In accordance with the CARES Act, the Company implemented loan modification programs in response to the COVID-19 pandemic in order to provide borrowers with flexibility with respect to repayment terms. The Company’s payment relief assistance includes forbearance, deferrals, extension and re-aging programs, along with certain other modification strategies. The Company elected the accounting policy in the CARES Act to not apply TDR accounting to loans modified for borrowers impacted by the COVID-19 pandemic if the concession meets the criteria as defined under the CARES Act. or purchased credit-deteriorated, otherwise referred to herein as PCD, assets are defined as acquired individual financial assets (or acquired groups of financial assets with similar risk characteristics) that, as of the date of acquisition, have experienced a more-than-insignificant deterioration in credit quality since origination, as determined by the Company’s assessment. The Company records acquired PCD loans by adding the expected credit losses (i.e., allowance for credit losses) to the purchase price of the financial assets rather than recording through the provision for credit losses in the income statement. The expected credit loss, as of the acquisition day, of a PCD loan is added to the allowance for credit losses. The non-credit discount or premium is the difference between the unpaid principal balance and the amortized cost basis as of the acquisition date. Subsequent to the acquisition date, the change in the ACL on PCD loans is recognized through the provision for credit losses. The non-credit discount or premium is accreted or amortized, respectively, into interest income over the remaining life of the PCD loan on a level-yield basis. In accordance with the transition requirements within the standard, the Company’s acquired credit-impaired loans (i.e., ACI or Purchased Credit Impaired) were treated as PCD loans. The Company follows its nonaccrual policy by reversing contractual interest income in the income statement when the Company places a loan on nonaccrual status. Therefore, Management excludes the accrued interest receivable balance from the amortized cost basis in measuring expected credit losses on the portfolio and does not record an allowance for credit losses on accrued interest receivable. As of December 31, 2020, the accrued interest receivable for loans recorded in Other Assets was $93.9 million. The Company has a variety of assets that have a component that qualifies as an off-balance sheet exposure. These primarily include undrawn portions of revolving lines of credit and standby letters of credit. The expected losses associated with these exposures within the unfunded portion of the expected credit loss will be recorded as a liability on the balance sheet with an offsetting income statement expense. Management has determined that a majority of the Company’s off-balance-sheet credit exposures are not unconditionally cancellable. As part of the new combined ACL methodology implemented during 2020, Management completed a funding study based on historical data to estimate the percentage of unfunded loan commitments that will ultimately be funded to calculate the reserve for unfunded commitments. Management applied this funding rate, along with the loss factor rate determined for each pooled loan segment, to unfunded loan commitments, excluding unconditionally cancellable exposures and letters of credit, to arrive at the reserve for unfunded loan commitments. As of December 31, 2020, the liability recorded for expected credit losses on unfunded commitments was $43.4 million. The current adjustment to the ACL for unfunded commitments is recognized through the provision for credit losses in the Statements of Income.
Other Real Estate Owned and Bank Property Held For Sale	Other Real Estate Owned and Bank Property Held For Sale ​ Other real estate owned (“OREO”) consists of properties obtained through foreclosure or through a deed in lieu of foreclosure in satisfaction of loans. Prior to the merger with CSFL, the Company classified former branch sites as held for sale OREO. During the second quarter of 2020 and with the merger with CSFL, the Company elected to reclassify these assets as bank property held for sale and report on a separate line on the Consolidated Balance Sheet. Both OREO and bank property held for sale are recorded at the lower of cost or fair value and the fair value was determined on the basis of current valuations obtained principally from independent sources, adjusted for estimated selling costs. At the time of foreclosure or initial possession of collateral, for OREO, any excess of the loan balance over the fair value of the real estate held as collateral is treated as a charge against the ACL. At the time a bank property is no longer in service and is moved to held for sale, any excess of the current book value over fair value is recorded as an expense in the Consolidated Statements of Income. Subsequent adjustments to this value are described in the following paragraph. The Company report subsequent declines in the fair value of OREO and bank properties held for sale below the new cost basis through valuation adjustments. Significant judgments and complex estimates are required in estimating the fair value of these properties, and the period of time within which such estimates can be considered current is significantly shortened during periods of market volatility. In response to market conditions and other economic factors, Management may utilize liquidation sales as part of its problem asset disposition strategy. As a result of the significant judgments required in estimating fair value and the variables involved in different methods of disposition, the net proceeds realized from sales transactions could differ significantly from the current valuations used to determine the fair value of these properties. Management reviews the value of these properties periodically and adjusts the values as appropriate. Revenue and expenses from OREO operations as well as gains or losses on sales and any subsequent adjustments to the value are recorded as OREO expense and loan related expense, a component of non-interest expense.
Business Combinations and Method of Accounting for Loans Acquired	B usiness Combinations and Method of Accounting for Loans Acquired The Company accounts for its acquisitions under Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 805, Business Combinations Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , on January 1, 2020 which now requires us to record purchased financial assets with credit deterioration (PCD assets), defined as a more-than-insignificant deterioration in credit quality since origination or issuance, at the purchase price plus the allowance for credit losses expected at the time of acquisition. Under this method, there is no credit loss expense affecting net income on acquisition of PCD assets. Changes in estimates of expected credit losses after acquisition are recognized as credit loss expense (or reversal of credit loss expense) in subsequent periods as they arise. Any non-credit discount or premium resulting from acquiring a pool of purchased financial assets with credit deterioration shall be allocated to each individual asset. At the acquisition date, the initial allowance for credit losses determined on a collective basis shall be allocated to individual assets to appropriately allocate any non-credit discount or premium. The non-credit discount or premium, after the adjustment for the allowance for credit losses, shall be accreted to interest income using the interest method based on the effective interest rate determined after the adjustment for credit losses at the adoption date. ​ A purchased financial asset that does not qualify as a PCD asset is accounted for similar to an originated financial asset. Generally, this means that an entity recognizes the allowance for credit losses for non-PCD assets through net income at the time of acquisition. In addition, both the credit discount and non-credit discount or premium resulting from acquiring a pool of purchased financial assets that do not qualify as PCD assets shall be allocated to each individual asset. This combined discount or premium shall be accreted to interest income using the effective yield method. ​ For further discussion of our loan accounting and acquisitions, see Note 2—Mergers and Acquisitions, Note 5—Loans and Note 6—Allowance for Credit Losses to the audited condensed consolidated financial statements.
Premises and Equipment	Premises and Equipment Land is carried at cost. Office equipment, furnishings, and buildings are carried at cost less accumulated depreciation computed principally on the declining-balance and straight-line methods over the estimated useful lives of the assets. Leasehold improvements are amortized on the straight-line method over the shorter of the estimated useful lives of the improvements or the terms of the related leases including lease renewals only when the Company is reasonably assured of the aggregate term of the lease. Additions to premises and equipment and major replacements are added to the accounts at cost. Maintenance and repairs and minor replacements are charged to expense when incurred. Gains and losses on routine dispositions are reflected in current operations.
Leases (Topic 842) and Method of Adoption	Leases (Topic 842) and Method of Adoption ​ On January 1, 2019, we adopted the requirements of Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842). Topic 842 was subsequently amended by ASU No. 2018-01, Land Easement Practical Expedient for Transition to Topic 842; ASU No. 2018-10, Codification Improvements to Topic 842, Leases; ASU No. 2018-11, Targeted Improvements; and ASU No. 2019-01, Codification Improvements to Topic 842 Leases. The purpose of the update was to increase transparency and comparability between organizations that enter into lease agreements. The key difference between the previous guidance and the update is the recognition of a right-of-use asset (ROU) and lease liability on the statement of financial position for those leases previously classified as operating leases under the old guidance. Accounting Standards Codification (“ASC”) Topic 842 defines a lease as a contract, or part of a contract, that conveys the right to control the use of identified property, plant, or equipment (an identified asset) for a period of time in exchange for consideration. In applying this standard, we reviewed our material contracts to determine if they included a lease by this new definition and did not identify any new leases. Our lease agreements in which ASC Topic 842 has been applied are primarily for real estate properties, including retail branch locations, operations and administration locations and stand-alone ATM locations. These leases have lease terms from greater than . Related to lease payment terms, some are fixed payments or based on a fixed annual increases while others are variable and the annual increases are based on market rates. The Company performed an analysis on equipment leases for the implementation of ASC Topic 842 and determined the number and dollar amount of our equipment leases was not material. ​ A modified retrospective transition approach is required, applying the new standard to all leases existing at the date of initial application. An entity may choose to use either (1) its effective date or (2) the beginning of the earliest comparative period presented in the financial statements as its date of initial application. We chose the transition method of adoption provided by ASU 2018-11, Leases (Topic 842) – Targeted Improvements, where we initially apply the new lease standard at the effective date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption if applicable. Therefore, we applied this standard to all existing leases as of the adoption date of January 1, 2019, recording a ROU asset and a lease liability in an equal amount. We did not have a cumulative-effect adjustment to the opening balance of retained earnings. With this transition method, we did not have to restate comparative prior periods presented in the financial statements related to ASC Topic 842, but will present comparative prior periods disclosures using the previous accounting guidance for leases. This adoption method is considered a change in accounting principle requiring additional disclosure of the nature of and reason for the change, which is solely a result of the adoption of the required standard. ​ ASC Topic 842 provides a package of practical expedients in applying the lease standard that had to be chosen at the date of adoption. We chose to elect this package of practical expedients. With this election, we do not have to reassess whether any expired or existing contracts are or contain a lease, do not have to reassess the classification of any expired or existing leases, do not have to separate lease and non-lease components and can account for both as a single lease component, and do not have to reassess initial direct costs or cash incentives for any existing leases due to immateriality. In addition, we chose not to apply ASC Topic 842 to short-term leases (leases with terms of 12 months or less) and not to record an underlying ROU asset or lease liability based on the uncertainty around the renewal of these leases. The Company will recognize lease expense for such leases on a straight-line basis over the lease term. ​ ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. We determined that we do not have any leases classified as finance leases and that all of our leases are operating leases at adoption. Two finance leases were acquired through the merger with CSFL, though these leases are immaterial. ROU assets and liabilities for operating leases are recognized at commencement date based on present value of lease payments not yet paid, discounted using the discount rate for the lease at the lease commencement date over the lease term. For operating leases, lease expense is determined by the sum of the lease payments to be recognized on a straight-line basis over the lease term. Based on the transition method that we chose to follow, the commencement date of the lease term for all existing leases is January 1, 2019. The lease term used for the calculation of the initial ROU asset and lease liability will include the initial lease term in addition to any renewal options or termination costs in the lease that we think are reasonably certain to be exercised or incurred. We received input from several levels of management and our corporate real estate department in determining which options were reasonably certain to be exercised. A discount rate is also needed in the calculation of the initial ROU assets and lease liability. ASC Topic 842 requires that the implicit rate within the lease agreement be used if available. If not available, we should use its incremental borrowing rate in effect at the time of the lease commencement date. We looked at the incremental borrowing rate from several of our borrowing sources to determine an average rate to be used in the calculation of the initial ROU asset and lease liability. The Company also considered the term of the borrowings as they relate to the terms of the leases. ​ liability million at the commencement date of January 1, 2019. We did not have a cumulative-effect adjustment to the opening balance of retained earnings at commencement. As of December 31, 2020, we had ROU assets of million recorded within other liabilities on the balance sheet. The adoption of ASC Topic 842 did not have a material impact on our consolidated income statement.
Bank Owned Life Insurance	Bank Owned Life Insurance Bank owned life insurance (BOLI) are comprised of long-term life insurance contracts on the lives of certain current and past employees where the insurance policy benefits and ownership are retained by the employer. Its cash surrender value is an asset that the Company uses to partially offset the future cost of employee benefits. The cash value accumulation on BOLI is permanently tax deferred if the policy is held to the insured person’s death and certain other conditions are met.
Intangible Assets	Intangible Assets Intangible assets consist of goodwill, core deposit intangibles, client list intangibles, and noncompetition agreement (“noncompete”) intangibles that result from the acquisition of other banks or branches from other financial institutions. Core deposit intangibles represent the value of long-term deposit relationships acquired in these transactions. Client list intangibles represent the value of long- term client relationships for the wealth and trust management business. Noncompete intangibles represent the value of key personnel relative to various competitive factors such as ability to compete, willingness or likelihood to compete, and feasibility based upon the competitive environment, and what the Bank could lose from competition. Goodwill represents the excess of the purchase price over the sum of the estimated fair values of the tangible and identifiable intangible assets acquired less the estimated fair value of the liabilities assumed in a business combination. At December 31, 2020 and December 31, 201 billion, respectively. Goodwill has an indefinite useful life and is evaluated for impairment annually or more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount exceeds the asset’s fair value. In January 2017, the FASB issued ASU No. 2017-04, which simplifies the accounting for goodwill impairment for all entities by requiring impairment charges to be based on Step 1 of the previous accounting guidance’s two-step impairment test under ASC Topic 350. Under the new guidance, if a reporting unit’s carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. The impairment charge will be limited to the amount of goodwill allocated to that reporting unit. The new standard eliminates the requirement to calculate a goodwill impairment charge using Step 2 which involved calculating an implied fair value of goodwill for each reporting unit for which the first step indicated impairment. The standard does not change the guidance on completing Step 1 of the goodwill impairment test. An entity will still be able to perform today’s optional qualitative goodwill impairment assessment before determining whether to proceed to the quantitative step of determining whether the reporting unit’s carrying amount exceeds it fair value. ​ The Company evaluated the carrying value of goodwill as of April 30, 2020, our annual test date, considering the effects of COVID-19 and determined that no impairment charge was necessary. ​ Core deposit intangibles, client list intangibles, and noncompetition (“noncompete”) intangibles consist primarily of amortizing assets established during the acquisition of other banks. This includes whole bank acquisitions and the acquisition of certain assets and liabilities from other financial institutions. Core deposit intangibles represent the estimated value of long-term deposit relationships acquired in these transactions. 10 an accelerated basis method which reasonably approximates the anticipated benefit stream from the accounts. The estimated useful lives are periodically reviewed for reasonableness. Client list intangibles represent the value of long-term client relationships for the correspondent banking and wealth and trust management business. line method. The estimated useful lives are periodically reviewed for reasonableness. Noncompete intangibles represent the value of key personnel relative to various competitive factors such as ability to compete, willingness or likelihood to compete, and feasibility based upon the competitive environment, and what the Bank could lose from competition. 2 line method. The estimated useful lives are periodically reviewed for reasonableness.
Mortgage Servicing Rights	Mortgage Servicing Rights
Transfer of Financial Assets	Transfer of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over the transferred assets is deemed to be surrendered when: (1) the assets have been isolated from the Company, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. The Company reviews all sales of loans by evaluating specific terms in the sales documents and believes that the criteria discussed above to qualify for sales treatment have been met as loans have been transferred for cash and the notes and mortgages for all loans in each sale are endorsed and assigned to the transferee. As stated in the commitment document, the Buyer has no recourse with these loans except in the case of fraud. In certain sales, mortgage servicing rights may be retained and in other programs potential loss exposure from the credit enhancement obligation may be retained, both of which are evaluated and appropriately measured at the date of sale. ​ The Company packages fixed rate conforming mortgage loans as securities to investors issued through Fannie Mae and sold to third party investors or sells them to satisfy cash forward mandatory commitments to Fannie Mae. The Company records loan securitizations or cash forwards as a sale when the transferred loans are legally isolated from its creditors and the accounting criteria for a sale are met. Gains or losses recorded on loan securitizations and cash forwards depend in part on the net carrying amount of the loans sold, which is allocated between the loans sold and retained interests based on their relative fair values at the date of sale. The Company generally retains mortgage servicing rights on residential mortgage loans sold in the secondary market. Loans transferred to “held-for-sale” with the intention of disposal through a bulk loan sale will be sold with servicing released. Since quoted market prices are not typically available, the fair value of retained interests is estimated through the services of a third party service provider to determine the net present value of expected future cash flows. Such models incorporate management’s best estimates of key variables, such as prepayment speeds and discount rates that would be used by market participants and are appropriate for the risks involved. Gains and losses incurred on loans sold to third party investors are included in mortgage banking income in the Consolidated Statements of Income.
Revenue from Contracts with Customers (Topic 606) and Method of Adoption	Revenue from Contracts with Customers (Topic 606) and Method of Adoption ​ On January 1, 2018, we adopted the requirements of Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (“ASU Topic 606”). The majority of our revenue is derived primarily from interest income from receivables (loans) and securities. Other revenues are derived from fees received in connection with deposit accounts, mortgage banking activities including gains from the sale of loans and loan origination fees, correspondent banking activities including revenue from the sale of fixed income securities and fees from hedging services, and trust and investment advisory services. The core principle of the new standard is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ​ The Company adopted ASU Topic 606 using the retrospective transition approach which requires restatement of prior periods. The Company selected this method even though there were no material changes in the timing of revenue recognition due to the fact that ASU Topic 606 requires us to report network costs associated with debit card and ATM transactions netted against the related fees from such transactions. Previously, such network costs were reported as a component of other noninterest expense. The Company restated prior periods for this reclassification. For years 2020, 2019, and 2018, gross interchange and debit card transaction fees totaled million, respectively. On a net basis, the Company reported million, respectively, as interchange and debit card transactions fees in the accompanying Consolidated Statements of Income as noninterest income for the years ended December 31, 2020, 2019, and 2018. This adoption method is considered a change in accounting principle requiring additional disclosure of the nature of and reason for the change, which is solely a result of the adoption of the required standard. When applying the retrospective approach under ASU Topic 606, the Company has elected, as a practical expedient, to apply the revenue standard only to contracts that are not completed as of January 1, 2018. A completed contract is considered to be a contract for which all (or substantially all) of the revenue was recognized in accordance with revenue guidance that was in effect before January 1, 2018. There were no uncompleted contracts as of January 1, 2018 for which application of the new standard required an adjustment to retained earnings. ​ The following disclosures related to ASU Topic 606 involve income derived from contracts with customers. Within the scope of ASU Topic 606, the Company maintains contracts to provide services, primarily for investment advisory and/or custody of assets. Through the Company’s wholly owned subsidiaries, the Bank, and South State Advisory, Inc., the Company contracts with its customers to perform IRA, Trust, and/or Custody and Agency advisory services. million for the years ended December 31, 2020, 2019 and 2018. Due to the nature of our relationship with the customers that we provide services, we do not incur costs to obtain contracts and there are no material incremental costs to fulfill these contracts that should be capitalized. ​ Disaggregation of Revenue - million for the years ended December 31, 2020, 2019 and 2018. Total revenue derived from contracts in which services are transferred over time was million for the years ended December 31, 2020, 2019 and 2018. Revenue is recognized as the services are provided to the customers. Economic factors impacting the customers could affect the nature, amount, and timing of these cash flows, as unfavorable economic conditions could impair the customers’ ability to provide payment for services. This risk is mitigated as we generally deduct payments from customers’ accounts as services are rendered. ​ Contract Balances - The timing of revenue recognition, billings, and cash collections results in billed accounts receivable on our balance sheet. Most contracts call for payment by a charge or deduction to the respective customer account but there are some that require a receipt of payment from the customer. For fee per transaction contracts, the customers are billed as the transactions are processed. For hourly rate and monthly service contracts related to trust and some investment revenues, the customers are billed monthly (generally as a percentage basis point of the market value of the investment account). In some cases, specific to South State Advisory, Inc., customers are billed in advance for quarterly services to be performed based on the past quarter’s average account balance. These do create contract liabilities or deferred revenue, as the customers pay in advance for service. Neither the contract liabilities nor the accounts receivables balances are material to the Company’s balance sheet. ​ Performance Obligations - A performance obligation is a promise in a contract to transfer a distinct good or service to the customer, and is the unit of account in ASU Topic 606. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. The performance obligations for these contracts are satisfied as the service is provided to the customer (either over time or at a point in time). The payment terms of the contracts are typically based on a basis point percentage of the investment account market value, fee per hour of service, or fee for service incurred. There are no significant financing components in the contracts. Excluding deposit services revenues which are mostly billed at a point in time as a fee for services incurred, all other contracts within the scope of ASU Topic 606 contain variable consideration in that fees earned are derived from market values of accounts or from hours worked for services performed which determines the amount of consideration to which we are entitled. The variability is resolved when the hours are incurred or services are provided. The contracts do not include obligations for returns, refunds, or warranties. The contracts are specific to the amounts owed to the Company for services performed during a period should the contracts be terminated. ​ Significant Judgments - Revenue is recognized as services are billed to the customers. Variable consideration does exist for contracts related to our trust and investment services as revenues are based on market values and services performed. The Company has adopted the right-to-invoice practical expedient for trust management contracts through South State Bank which we contract with our customers to perform IRA, Trust, and/or Custody services.
Advertising Costs	Advertising Costs The Company expenses advertising costs as they are incurred and advertising communication costs the first time the advertising takes place. The Company may establish accruals for anticipated advertising expenses within the course of a fiscal year.
Comprehensive Income	Comprehensive Income Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Certain changes in assets and liabilities, such as (1) unrealized gains and losses on available-for-sale securities (2) unrealized gains and losses on effective portions of derivative financial instruments accounted for as cash flow hedges and (3) net change in unrecognized amounts related to pension and post-retirement benefits, are reported as a separate component of the equity section of the balance sheet. Such items, along with net income, are components of total comprehensive income (see Consolidated Statements of Comprehensive Income on page F-11).
Employee Benefit Plans	Employee Benefit Plans The Company’s defined benefit pension and other post retirement plans are accounted for in accordance with FASB ASC 715, Compensation—Retirement Benefits retirement benefit plans. The Company terminated its defined benefit pension plan in 2019. The expected costs of the post retirement benefit plans are being expensed over the period that employees provide service. The Employee Stock Purchase Plan (“ESPP”) allows for a look-back option which establishes the purchase price as an amount based on the lesser of the stock’s market price at the grant date or its market price at the exercise (or purchase) date. For the shares issued in exchange for employee services under the plan, the Company accounts for the plan under the FASB ASC 718, Compensation—Stock Compensation
Income Taxes	Income Taxes Income taxes are provided for the tax effects of the transactions reported in the accompanying consolidated financial statements and consist of taxes currently due plus deferred taxes related primarily to differences between the tax basis and financial statement basis of gains on acquisitions, available-for-sale securities, allowance for credit losses, write downs of OREO properties, accumulated depreciation, net operating loss carryforwards, accretion income, deferred compensation, intangible assets, mortgage servicing rights, and pension plan and post-retirement benefits. The deferred tax assets and liabilities represent the future tax return consequences of those differences, which will either be taxable or deductible when the assets and liabilities are recovered or settled. Deferred tax assets and liabilities are reflected at income tax rates applicable to the period in which the deferred tax assets or liabilities are expected to be realized or settled. As changes in tax laws or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. The Company recognizes interest and penalties accrued relative to unrecognized tax benefits in its respective federal or state income tax accounts. As of December 31, 2020 and 2019, there were no material accruals for uncertain tax positions. The Company and its subsidiaries file a consolidated federal income tax return. Additionally, income tax returns are filed by the Company or its subsidiaries in the state of South Carolina, Georgia, North Carolina, Florida, Virginia, Alabama, and Mississippi, Tennessee, California, Colorado, Texas, New York, and New York City. Generally, the Company’s federal and state income tax returns are no longer subject to examination by taxing authorities for years prior to 2017.
Earnings Per Share	Earnings Per Share Basic earnings per share (“EPS”) represents income available to common shareholders divided by the weighted-average number of shares outstanding during the year. Diluted earnings per share reflects additional shares that would have been outstanding if dilutive potential shares had been issued. Potential shares that may be issued by the Company relate solely to outstanding stock options, restricted stock and restricted stock units (non-vested shares), and warrants, and are determined using the treasury stock method. Under the treasury stock method, the number of incremental shares is determined by assuming the issuance of stock for the outstanding stock options and warrants, reduced by the number of shares assumed to be repurchased from the issuance proceeds, using the average market price for the year of the Company’s stock. Weighted-average shares for the basic and diluted EPS calculations have been reduced by the average number of unvested restricted shares.
Derivative Financial Instruments	Derivative Financial Instruments The Company’s interest rate risk management strategy incorporates the use of a derivative financial instrument, specifically an interest rate swap, to essentially convert a portion of its variable- rate debt to a fixed rate. Cash flows related to variable-rate debt will fluctuate with changes in an underlying rate index. When effectively hedged, the increases or decreases in cash flows related to the variable- rate debt will generally be offset by changes in cash flows of the derivative instrument designated as a hedge. This strategy is referred to as a cash flow hedge. For derivatives designated as hedging exposure to variable cash flows of a forecasted transaction (cash flow hedge), the derivative’s entire gain or loss is initially reported as a component of other comprehensive income and subsequently reclassified into earnings when the forecasted transaction affects earnings or when the hedge is terminated. For derivatives that are not designated as hedging instruments, changes in the fair value of the derivatives are recognized in earnings immediately. The Company also maintains loan swaps which are accounted for as a fair value hedge. This derivative protects the Company from interest rate risk caused by changes in the LIBOR curve in relation to a certain designated fixed rate loan. Fair value hedges convert the fixed rate to a floating rate (see Note 29—Derivative Financial Instruments). The Company’s risk management strategy for its mortgage banking activities incorporates derivative instruments used to hedge both the value of the mortgage servicing rights and the mortgage pipeline. These derivative instruments are not designated as hedges and are not speculative in nature. The derivative instruments that are used to hedge the value of the mortgage servicing rights include financial forwards, futures contracts, and options written and purchased. When-issued securities and mandatory cash forward trades are typically used to hedge the mortgage pipeline. These instruments derive their cash flows, and therefore their values, by reference to an underlying instrument, index or referenced interest rate. The Company’s risk management strategy also incorporates the use of interest rate swap contracts that help in managing interest rate risk within the loan portfolio and foreign currency exchange. These derivatives are not designated as hedges and are not speculative, and result from a service the Company provides to certain customers. The Company executes interest rate swaps with commercial banking customers to facilitate their respective risk management strategies. Those interest rate swaps are simultaneously hedged by offsetting interest rate swaps that the Company executes with a third party, such that the Company minimizes its net risk exposure resulting from such transactions. As the interest rate swaps associated with this program do not meet the strict hedge accounting requirements, changes in the fair value of both the customer swaps and the offsetting swaps are recognized directly in earnings (See Note 29—Derivative Financial Instruments). By using derivative instruments, the Company is exposed to credit and market risk. If the counterparty fails to perform, credit risk is equal to the fair value gain in a derivative. When the fair value of a derivative contract is positive, this situation generally indicates that the counterparty is obligated to pay the Company, and, therefore, creates a repayment risk for the Company. When the fair value of a derivative contract is negative, the Company is obligated to pay the counterparty and, therefore, has no repayment risk. The Company minimizes the credit risk in derivative instruments by entering into transactions with high-quality counterparties that are reviewed periodically by the Company. The Company’s derivative activities are monitored by its Asset-Liability Management Committee as part of that committee’s oversight of the Company’s asset/liability and treasury functions. The Company’s Asset-Liability Management Committee is responsible for implementing various hedging strategies that are developed through its analysis of data from financial simulation models and other internal and industry sources. The resulting hedging strategies are then incorporated into the overall interest-rate risk management process. The Company recognizes the fair value of derivatives as assets or liabilities in the financial statements. The accounting for the changes in the fair value of a derivative depends on the intended use of the derivative instrument at inception. The change in fair value of the effective portion of cash flow hedges is accounted for in other comprehensive income rather than net income. Changes in fair value of derivative instruments that are not intended as a hedge are accounted for in the net income in the period of the change (see Note 29—Derivative Financial Instruments for further disclosure).
Reclassification	Reclassification Certain amounts previously reported have been reclassified to conform to the current year’s presentation. Such reclassifications had no effect on net income and shareholders’ equity.
Subsequent Events	Subsequent Events The Company has evaluated subsequent events for accounting and disclosure purposes through the date the financial statements are issued. See Note 32—Subsequent Events for further information.
Recent Accounting and Regulatory Pronouncements	Recent Accounting and Regulatory Pronouncements Accounting Standards Adopted in 2020 In February 2020, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2020-02, Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 119 and Update to SEC Section of Effective Date Related to Accounting Standards Update No. 2016-02, Leases (Topic 842 ). This update adds the content of SEC Staff Accounting Bulletin (“SAB”) No. 119 to the FASB Codification. SAB No.119 provides interpretive guidance on methodologies and supporting documentation for measuring credit losses, with a focus on the documentation the staff would normally expect registrants engaged in lending transactions to prepare and maintain to support estimates of current expected credit losses for loan transactions. The ASU also updates the SEC section of the FASB Codification for the delay in the effective date of Topic 842 for public business entities that otherwise would not meet the definition of a public business entity except for a requirement to include its financial information in another entity’s filing with the SEC. The clarification related to SAB No. 119 was adopted in the first quarter of 2020 when ASU 2016-13 was adopted. See ASU 2016-13 below for overall effect of Topic 326 Financial Instruments-Credit Losses on our consolidated financial statements. The change in the effective date for ASU 2016-02 – Leases did not affect the Company in that we adopted the standard in 2019. ​ In November 2019, the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815. This update, related to ASU 2016-01, clarifies certain aspects brought to the Account Standards Board attention by stakeholders related to these ASUs, but does not change the core principles of these standards. The areas of improvement clarified in this update are related to 1) expected recoveries for purchased financial assets with credit deterioration, 2) transition relief for troubled debt restructurings, 3) disclosures related to accrued interest receivables, 4) financial assets secured by collateral maintenance provisions and 5) conforming amendment to Subtopic 805-20. This clarification was adopted in the first quarter of 2020 when the overall standard was adopted. See ASU 2016-13 below for overall effect of Topic 326 Financial Instruments-Credit Losses ​ In April 2019, the FASB issued ASU No. 2019-05, Targeted Transition Relief (Topic 326 – Financial Instruments-Credit Losses). This update provides entities that have certain instruments within the scope of Subtopic 326-20, Financial Instruments—Credit Losses— Measured at Amortized Cost, with an option to irrevocably elect the fair value option in Subtopic 825-10 applied on an instrument-by-instrument basis for eligible instruments, upon adoption of Topic 326. The fair value option election does not apply to held-to-maturity debt securities. An entity that elects the fair value option should subsequently apply the guidance in Subtopics 820-10, Fair Value Measurement—Overall, and 825-10. This update was adopted in the first quarter of 2020 when the overall standard was adopted. See ASU 2016-13 below for overall effect of Topic 326 Financial Instruments-Credit Losses ​ In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments. This update related to ASU 2016-01, ASU 2017-12 and ASU 2016-13 clarifies certain aspects brought to the Account Standards Board attention by stakeholders related to these ASUs, but does not change the core principles of these standards. The clarifications related to ASU 2016-01 and 2017-12 were adopted in the second quarter of 2019 and did not have a material impact on our consolidated financial statements. The clarifications related to ASU 2016-13 were adopted in the first quarter of 2020 when the overall standard was adopted. See ASU 2016-13 below for overall effect of Topic 326 Financial Instruments-Credit Losses ​ In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement (Topic 820) . ASU 2018-13 removes, modifies, and adds certain disclosure requirements in ASC 820 related to Fair Value Measurement on the basis of the concepts in the FASB Concepts Statement Conceptual Framework for Financial Reporting — Chapter 8: Notes to Financial Statements . ASU 2018-13 was effective for all entities for fiscal years beginning after December 15, 2019, including interim periods therein. The ASU requires application of the prospective method of transition (for only the most recent interim or annual period presented in the initial fiscal year of adoption) to the new disclosure requirement additions. The ASU also requires prospective application to any modifications to disclosures made because of the change to the requirements for the narrative description of measurement uncertainty. The effects of all other amendments made by the ASU must be applied retrospectively to all periods presented. This update did not have a material impact on our consolidated financial statements. ​ In January 2017, the FASB issued ASU No. 2017-04, Intangible-Goodwill and other (Topic 350): Simplifying the Test for Goodwill Impairment . ASU 2017-04 simplifies the accounting for goodwill impairment for all entities by requiring impairment charges to be based on the first step in today’s two-step impairment test under ASC Topic 350 and eliminating Step 2 from the goodwill impairment test. As amended, the goodwill impairment test consists of one step comparing the fair value of a reporting unit with its carrying amount. An entity should recognize a goodwill impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. The guidance was effective for public business entities for fiscal years beginning after December 15, 2019, and interim periods within those years. Based on effects of the COVID-19 pandemic on the economy and on our stock price, the Company began evaluating its goodwill on a quarterly basis per ASU 2017-04. The most recent analysis as of December 31, 2020 determined there was impairment of goodwill or other intangibles. The Company will continue to monitor if a triggering event occurs that requires goodwill to be evaluated again. ​ In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 requires an entity to utilize a new impairment model known as the current expected credit loss (“CECL”) model to estimate its lifetime “expected credit loss” and record an ACL that, when deducted from the amortized cost basis of the financial asset, presents the net amount expected to be collected on the financial asset. The CECL model is expected to result in earlier recognition of credit losses for loans, investment securities portfolio, and purchased financial assets with credit deterioration. See Note 1 Summary of Significant Account Policies – Allowance for Credit Losses for further discussion. We adopted the new standard as of January 1, 2020. This standard did not have a material impact on our investment securities portfolio at implementation. Related to the implementation of ASU 2016-13, the Company recorded additional ACL for loans of million. See table below for impact of ASU 2016-13 on the Company’s consolidated balance sheet. See Note 1—Summary of Significant Accounting Policies for further discussion. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 1, 2020 ​ ​ ​ ​ ​ As Reported Under ​ Pre-ASC 326 ​ Impact of ASC 326 ​ Dollars in thousands ASC 326 Adoption Adoption ​ ​ ​ ​ ​ ​ ​ ​ Assets: ​ ​ ​ ​ ​ ​ ​ Allowance for Credit Losses on Debt Securities ​ ​ ​ ​ ​ ​ ​ Investment Securities - Available-for-sale $ 1,956,047 $ 1,956,047 $ — A Investment Securities - Held-to-maturity ​ — ​ — ​ — A Loans ​ ​ ​ ​ ​ ​ ​ Non - Acquired Loans ​ 9,252,831 ​ 9,252,831 ​ — ​ Acquired Loans ​ 2,118,940 ​ 2,117,209 ​ 1,723 B Allowance for Credit Losses on Loans ​ (111,365) ​ (56,927) ​ (54,438) C Deferred Tax Asset ​ 43,955 ​ 31,316 ​ 12,639 D Accrued Interest Receivable - Loans ​ 30,009 ​ 28,332 ​ 1,677 B ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ Reserve for Loan Losses - Unfunded Commitments ​ 6,756 ​ 335 ​ 6,421 E ​ ​ ​ ​ ​ ​ ​ ​ Equity: ​ ​ ​ ​ ​ ​ ​ Retained Earnings ​ 635,075 ​ 679,895 ​ (44,820) F A - The Company did not have any held-to maturity securities as of January 1, 2020. Per our analysis we determined that no ACL was necessary for investment securities – available-for-sale. B – Accrued interest receivable from acquired credit impaired loans of $1,677 was reclassified to other assets and was offset by the reclass of the grossed up credit discount on acquired credit impaired loans of $3,408 that was moved to the ACL for the purchased credit deteriorated loans. C – This is the calculated adjustment to the ACL related to the adoption of ASC 326. Additional reserve related to non-acquired loans was D – This is the effect of deferred tax assets related to the adjustment to the ACL from the adoption of ASC 326 using a 22% tax rate. E – This is the adjustment to the reserve for unfunded commitments related to the adoption of ASC 326. F – This is the net adjustment to retained earnings related to the adoption of ASC 326. ​ Issued But Not Yet Adopted Accounting Standards In March 2020, FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848 – Facilitation of the Effects of Reference Rate Reform on Financial Reporting and subsequently expanded the scope of ASU No. 2020-04 with the issuance of ASU No. 2021-01 . These updates provide companies with optional guidance to ease the potential accounting burden associated with transitioning away from reference rates that are expected to be discontinued. The amendments in this update apply only to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. The amendments in this update were effective for all entities as of March 12, 2020 through December 31, 2022. An entity may elect to apply the amendments in this update to eligible hedging relationships existing as of the beginning of the interim period that includes March 12, 2020 and to new eligible hedging relationships entered into after the beginning of the interim period that includes March 12, 2020. An entity may elect to apply the amendments for contract modifications as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. Once elected, the amendments in this update must be applied prospectively for all eligible contract modifications and hedging relationships. ​ In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740) – Simplifying the Accounting for Income Taxes. The amendments in this update simplify the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments also improve consistent application of and simplify GAAP for other areas of Topic 740 by clarifying the amending existing guidance. Some of the simplification items included are 1) simplification for intra-period tax allocations where entities will determine the tax effect of pre-tax income or loss from continuing operations without consideration of the tax effect of other items that are not included in continuing operations, 2) simplification for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year allowing an entity to record a benefit for year-to-date loss in excess of its forecasted loss, and 3) simplify the accounting for income taxes by requiring that an entity recognize a franchise tax (or similar tax) that is partially based on income as an income-based tax and account for any incremental amount incurred as a non-income-based tax. This guidance is effective for interim and annual reporting periods beginning after December 15, 2020. Early adoption is permitted. The amendments related to franchise taxes that are partially based on income should be applied on either a retrospective basis for all periods presented or a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. All other amendments should be applied on a prospective basis. The Company does not believe this update will have a material impact on our consolidated financial statements. ​ In August 2018, the FASB issued ASU No. 2018-14, Disclosure Framework-Changes to the Disclosure Requirements for Defined Benefit Plans (Subtopic 715-20 . ASU 2018-14 amends ASC 715-20 to add, remove, and clarify disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. For public business entities, ASU 2018-14 is effective for fiscal years ending after December 15, 2020 and requires entities to apply the amendment on a retrospective basis. Early adoption is permitted. The Company does not believe that this guidance will have a material impact on our consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Summary of Significant Accounting Policies
Summary of impact of ASU	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 1, 2020 ​ ​ ​ ​ ​ As Reported Under ​ Pre-ASC 326 ​ Impact of ASC 326 ​ Dollars in thousands ASC 326 Adoption Adoption ​ ​ ​ ​ ​ ​ ​ ​ Assets: ​ ​ ​ ​ ​ ​ ​ Allowance for Credit Losses on Debt Securities ​ ​ ​ ​ ​ ​ ​ Investment Securities - Available-for-sale $ 1,956,047 $ 1,956,047 $ — A Investment Securities - Held-to-maturity ​ — ​ — ​ — A Loans ​ ​ ​ ​ ​ ​ ​ Non - Acquired Loans ​ 9,252,831 ​ 9,252,831 ​ — ​ Acquired Loans ​ 2,118,940 ​ 2,117,209 ​ 1,723 B Allowance for Credit Losses on Loans ​ (111,365) ​ (56,927) ​ (54,438) C Deferred Tax Asset ​ 43,955 ​ 31,316 ​ 12,639 D Accrued Interest Receivable - Loans ​ 30,009 ​ 28,332 ​ 1,677 B ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ Reserve for Loan Losses - Unfunded Commitments ​ 6,756 ​ 335 ​ 6,421 E ​ ​ ​ ​ ​ ​ ​ ​ Equity: ​ ​ ​ ​ ​ ​ ​ Retained Earnings ​ 635,075 ​ 679,895 ​ (44,820) F A - The Company did not have any held-to maturity securities as of January 1, 2020. Per our analysis we determined that no ACL was necessary for investment securities – available-for-sale. B – Accrued interest receivable from acquired credit impaired loans of $1,677 was reclassified to other assets and was offset by the reclass of the grossed up credit discount on acquired credit impaired loans of $3,408 that was moved to the ACL for the purchased credit deteriorated loans. C – This is the calculated adjustment to the ACL related to the adoption of ASC 326. Additional reserve related to non-acquired loans was D – This is the effect of deferred tax assets related to the adjustment to the ACL from the adoption of ASC 326 using a 22% tax rate. E – This is the adjustment to the reserve for unfunded commitments related to the adoption of ASC 326. F – This is the net adjustment to retained earnings related to the adoption of ASC 326.

Mergers and Acquisitions (Table

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2020
Mergers and Acquisitions
Schedule of proforma information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pro Forma ​ Pro Forma ​ ​ Year Ended ​ Year Ended (Dollars in thousands) ​ December 31, 2020 ​ December 31, 2019 Total revenues (net interest income plus noninterest income) $ 1,508,215 $ 1,368,452 Net interest income ​ $ 1,047,014 ​ $ 1,058,827 Net adjusted income available to the common shareholder ​ $ 385,390 ​ $ 412,515 EPS - basic ​ $ 5.44 ​ $ 5.85 EPS - diluted ​ $ 5.42 ​ $ 5.81
CSFL
Mergers and Acquisitions
Schedule of assets acquired, liabilities assumed, and fair value of total consideration transferred	The CSFL transaction was accounted for using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed and consideration exchanged were recorded at estimated fair value on the acquisition date. Fair values are preliminary and subject to refinement for up to a year after the closing date of the acquisition. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Initial ​ Subsequent ​ ​ ​ ​ ​ As Recorded ​ Fair Value ​ Fair Value ​ As Recorded by ​ (Dollars in thousands) by CSFL Adjustments Adjustments ​ the Company Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 2,566,450 ​ $ — ​ $ — ​ $ 2,566,450 ​ Investment securities ​ ​ 1,188,403 ​ ​ 5,507 (a) ​ — ​ ​ 1,193,910 ​ Loans held for sale ​ ​ 453,578 ​ ​ — ​ ​ — ​ ​ 453,578 ​ Loans, net of allowance and mark ​ 12,969,091 ​ (48,342) (b) ​ 29,834 (b) 12,950,583 ​ Premises and equipment ​ 308,150 ​ 2,392 (c) ​ 2,893 (c) 313,435 ​ Intangible assets ​ ​ 1,294,211 ​ ​ (1,163,349) (d) ​ 10,000 (d) ​ 140,862 ​ OREO and repossessed assets ​ ​ 10,849 ​ ​ (791) (e) ​ (49) (e) ​ 10,009 ​ Bank owned life insurance ​ ​ 333,053 ​ ​ — ​ ​ — ​ ​ 333,053 ​ Deferred tax asset ​ ​ 54,123 ​ ​ (8,681) (f) ​ (8,203) (f) ​ 37,239 ​ Other assets ​ 967,059 ​ (604) (g) ​ 642 (g) 967,097 ​ Total assets ​ $ 20,144,967 ​ $ (1,213,868) ​ $ 35,117 ​ $ 18,966,216 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Noninterest-bearing ​ $ 5,291,443 ​ $ — ​ $ — ​ $ 5,291,443 ​ Interest-bearing ​ 10,312,370 ​ 19,702 (h) ​ — ​ 10,332,072 ​ Total deposits ​ 15,603,813 ​ 19,702 ​ ​ — ​ 15,623,515 ​ Federal funds purchased and securities sold under agreements to repurchase ​ ​ 401,546 ​ ​ — ​ ​ — ​ ​ 401,546 ​ Other borrowings ​ ​ 278,900 ​ ​ (7,401) (i) ​ — ​ ​ 271,499 ​ Other liabilities ​ 977,725 ​ (4,592) (j) ​ 857 (j) 973,990 ​ Total liabilities ​ ​ 17,261,984 ​ ​ 7,709 ​ ​ 857 ​ ​ 17,270,550 ​ Net identifiable assets acquired over (under) liabilities assumed ​ ​ 2,882,983 ​ ​ (1,221,577) ​ ​ 34,260 ​ ​ 1,695,666 ​ Goodwill ​ — ​ 600,483 ​ ​ (39,441) ​ 561,042 ​ Net assets acquired over liabilities assumed ​ $ 2,882,983 ​ $ (621,094) ​ $ (5,181) ​ $ 2,256,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consideration: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ South State Corporation common shares issued ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 37,271,069 ​ Purchase price per share of the Company's common stock ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 60.27 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Company common stock issued ($2,246,327) and cash exchanged for fractional shares ($74) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,246,401 ​ Stock option conversion ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2,900 ​ Restricted stock conversion ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7,407 ​ Fair value of total consideration transferred ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,256,708 (k) ​ Explanation of fair value adjustments (a)— Represents the reversal of CSFL's existing fair value adjustments of $40.7 million and the adjustment to record securities at fair value (premium) totaling $46.2 million (includes reclassification of all securities held as HTM to AFS totaling $175.7 million). (b)— Represents approximately 2.04%, or $269.1 million, total mark of the loan portfolio including a 1.97%, or $259.7 million credit mark, based on a third party valuation. Also, includes the reversal of CSFL's ending allowance for credit losses of million. Fair value was subsequently adjusted by (c)— Represents the MTM adjustment of $4.0 million on leased assets partially offset by the write-off of de minimis fixed assets of $1.6 million. Subsequently, the fair value on certain bank premises was adjusted by (d)— Represents approximately a 1.28% core deposit intangible, or $125.9 million from a third party valuation. This amount is net of $84.9 million existing core deposit intangible and $1.2 billion of existing goodwill from CSFL’s prior transactions that was reversed. Approximately (e)— Represents the reversal of prior valuation reserves of $878,000 and recorded new valuation reserves of $1.7 million on both OREO and other repossessed assets. The fair value was subsequently adjusted based on gains and losses recognized from sales of OREO and other repossessed assets. (f)— Represents deferred tax assets related to fair value adjustments measured using an estimated tax rate of 22.0% . This includes an adjustment from the CSFL tax rate to our tax rate. The difference in tax rates relates to state income taxes. Additional deferred tax liability related to subsequent fair value adjustments identified and an updated estimated tax rate of (g)— Represents a valuation reserve of bank property held for sale of $3.2 million and a fair value adjustment of a lease receivable of $116,000. These amounts are offset by positive fair value adjustment for investment in low income housing of $3.3 million. (h)— Represents estimated premium for fixed maturity time deposits of $20.2 million partially offset by the reversal of existing CSFL fair value adjustments related to time deposit marks from other merger transactions of $546,000. (i)— Represents the recording of a discount of $12.5 million on TRUPs from a third party valuation partially offset by the reversal of the existing CSFL discount on TRUPs and other debt of $5.1 million. (j)— Represents the reversal of an existing $7.1 million unfunded commitment reserve at purchase date partially offset by a fair value adjustment to increase lease liabilities associated with leased facilities totaling $2.5 million. The discount rate applied to the bank owned life insurance split dollar liability was subsequently adjusted resulting in an increase in the other liability of $857,000. (k)—The purchase price, or the fair value of total consideration transferred, decreased by $5.2 million to $2.9 million for stock options assumed and converted in the merger. The stock options assumed reflect their intrinsic value based upon a Black Sholes valuation.

Trading Securities (Tables)

Trading Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Trading Securities
Schedule of trading securities	​ ​ ​ ​ ​ (Dollars in thousands) 2020 Beginning balance, June 7, 2020 ​ $ — Purchases ​ ​ 201,095 Proceeds from sale ​ ​ (190,907) Net realized gain on sales ​ 338 Net unrealized gains ​ 148 Ending balance ​ $ 10,674

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Investment Securities
Schedule of amortized cost and fair value of investment securities held to maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Gross ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair (Dollars in thousands) Cost Gains Losses Value December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt* ​ $ 25,000 ​ $ 1 ​ $ — ​ $ 25,001 ​ Mortgage-backed securities** ​ ​ 930,542 ​ ​ 2,763 ​ ​ (1,123) ​ ​ 932,182 ​ ​ ​ $ 955,542 ​ $ 2,764 ​ $ (1,123) ​ $ 957,183 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State and municipal obligations ​ $ — ​ $ — ​ $ — ​ $ — ​
Schedule of amortized cost and fair value of investment securities available for sale	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair (Dollars in thousands) Cost Gains Losses Value December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt* ​ $ 29,882 ​ $ 16 ​ $ (642) ​ $ 29,256 ​ State and municipal obligations ​ 502,575 ​ 17,491 ​ (27) ​ 520,039 ​ Mortgage-backed securities** ​ 2,722,018 ​ 49,153 ​ (3,496) ​ 2,767,675 ​ Corporate securities ​ ​ 13,562 ​ ​ 140 ​ ​ — ​ ​ 13,702 ​ ​ ​ $ 3,268,037 ​ $ 66,800 ​ $ (4,165) ​ $ 3,330,672 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt* ​ $ 25,356 ​ $ 585 ​ $ — ​ $ 25,941 ​ State and municipal obligations ​ 204,150 ​ 5,029 ​ (764) ​ 208,415 ​ Mortgage-backed securities** ​ 1,711,257 ​ 14,209 ​ (3,775) ​ 1,721,691 ​ ​ ​ $ 1,940,763 ​ $ 19,823 ​ $ (4,539) ​ $ 1,956,047 ​ * The Company’s government-sponsored entities holdings are comprised of debt securities offered by Federal Home Loan Mortgage Corporation (“FHLMC”) or Freddie Mac, Federal National Mortgage Association (“FNMA”) or Fannie Mae, FHLB, and Federal Farm Credit Banks (“FFCB”). ** All of the mortgage-backed securities are issued by government-sponsored entities; there are no private-label holdings. Also included in the Company’s government-sponsored entities are debt securities offered by the Small Business Administration (“SBA”), which have the full faith and credit backing of the United States Government. ​
Schedule of amortized cost and carrying value of other investment securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying (Dollars in thousands) Value December 31, 2020: ​ ​ ​ ​ Federal Home Loan Bank stock ​ $ 15,083 ​ Federal Reserve Bank stock ​ ​ 129,871 ​ Investment in unconsolidated subsidiaries ​ 4,941 ​ Other nonmarketable investment securities ​ 10,548 ​ ​ ​ $ 160,443 ​ December 31, 2019: ​ ​ ​ ​ Federal Home Loan Bank stock ​ $ 43,044 ​ Investment in unconsolidated subsidiaries ​ 3,563 ​ Other nonmarketable investment securities ​ 2,517 ​ ​ ​ $ 49,124 ​
Schedule of amortized cost and fair value of debt and equity securities by contractual maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities ​ Securities ​ ​ Held-to-maturity ​ Available-for-sale ​ ​ Amortized ​ Fair ​ Amortized ​ Fair (Dollars in thousands) Cost Value Cost Value Due in one year or less $ — ​ $ — $ 9,669 $ 9,698 ​ Due after one year through five years ​ — ​ — ​ 80,846 ​ 83,586 ​ Due after five years through ten years ​ 88,735 ​ 89,007 ​ 525,547 ​ 539,905 ​ Due after ten years ​ 866,807 ​ 868,176 ​ 2,651,975 ​ 2,697,483 ​ ​ ​ $ 955,542 ​ $ 957,183 ​ $ 3,268,037 ​ $ 3,330,672 ​
Schedule of information with respect to sales of available-for-sale securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2020 2019 2018 Securities Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sale proceeds $ 100,754 $ 242,733 $ 73,054 ​ Gross realized gains ​ ​ 662 ​ ​ 6,030 ​ ​ 31 ​ Gross realized losses ​ (612) ​ (3,319) ​ (686) ​ Net realized gain (loss) ​ $ 50 ​ $ 2,711 ​ $ (655) ​
Schedule of securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less Than ​ Twelve Months ​ ​ Twelve Months ​ or More ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ Fair ​ Unrealized ​ Fair (Dollars in thousands) Losses Value Losses Value December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Held-to-maturity ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities ​ $ 1,123 ​ $ 240,591 ​ $ — ​ $ — ​ ​ ​ $ 1,123 ​ $ 240,591 ​ $ — ​ $ — ​ Securities Available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ $ 642 ​ $ 24,358 ​ $ — ​ $ — ​ State and municipal obligations ​ 27 ​ 8,620 ​ — ​ — ​ Mortgage-backed securities ​ 2,475 ​ 509,319 ​ 1,021 ​ 105,125 ​ ​ ​ $ 3,144 ​ $ 542,297 ​ $ 1,021 ​ $ 105,125 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ $ — ​ $ — ​ $ — ​ $ — ​ State and municipal obligations ​ 764 ​ 42,070 ​ — ​ — ​ Mortgage-backed securities ​ 2,422 ​ 461,658 ​ 1,353 ​ 141,982 ​ ​ ​ $ 3,186 ​ $ 503,728 ​ $ 1,353 ​ $ 141,982 ​

Loans (Tables)

Loans (Tables)	12 Months Ended
	Dec. 31, 2020
Summary of Loans
Summary of loans	The following is a summary of total loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2020 ​ 2019 Loans: ​ ​ ​ ​ ​ Construction and land development (1) ​ ​ $ 1,899,066 ​ $ 1,017,261 ​ Commercial non-owner occupied ​ ​ 5,931,323 ​ 2,323,967 ​ Commercial owner occupied real estate ​ ​ ​ 4,842,092 ​ ​ 2,158,701 ​ Consumer owner occupied (2) ​ ​ 4,108,042 ​ 2,706,960 ​ Home equity loans ​ ​ 1,336,689 ​ 758,020 ​ Commercial and industrial ​ ​ 5,047,147 ​ 1,386,327 ​ Other income producing property ​ ​ 587,448 ​ 346,554 ​ Consumer ​ ​ 894,334 ​ 663,422 ​ Other loans ​ ​ 17,993 ​ 13,892 ​ Total loans ​ ​ 24,664,134 ​ 11,375,104 ​ Less allowance for credit losses ​ ​ (457,309) ​ (61,991) ​ Loans, net ​ ​ $ 24,206,825 ​ $ 11,313,113 ​ (1) Construction and land development includes loans for both commercial construction and development, as well as loans for 1-4 family construction and lot loans. (2) Consumer owner occupied includes loans on both 1-4 family owner occupied property, as well as 1-4 family investment rental property.
Schedule of credit risk profile by risk grade of loans	​ The following table presents the credit risk profile by risk grade of commercial loans by origination year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loans ​ ​ (Dollars in thousands) Amortized Cost Basis by Origination Year ​ ​ As of December 31, 2020 2020 2019 2018 2017 2016 Prior Revolving Total Construction and land development ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 457,433 $ 410,075 $ 133,719 $ 79,345 $ 41,018 $ 53,104 $ 15,502 $ 1,190,196 Special mention 20,912 5,668 707 1,757 1,815 7,293 - 38,152 Substandard 389 2,800 763 2,087 201 3,669 - 9,909 Doubtful - - - - - 8 - 8 Total Construction and land development $ 478,734 $ 418,543 $ 135,189 $ 83,189 $ 43,034 $ 64,074 $ 15,502 $ 1,238,265 ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial non-owner occupied ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 799,175 $ 1,082,242 $ 844,988 $ 661,092 $ 676,895 $ 1,196,156 $ 58,021 $ 5,318,569 Special mention 42,492 76,890 111,466 44,790 38,637 131,015 - 445,290 Substandard 1,351 49,662 7,497 27,224 38,617 43,109 - 167,460 Doubtful - - - - - 4 - 4 Total Commercial non-owner occupied $ 843,018 $ 1,208,794 $ 963,951 $ 733,106 $ 754,149 $ 1,370,284 $ 58,021 $ 5,931,323 ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial Owner Occupied ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 805,192 $ 957,412 $ 721,808 $ 603,785 $ 458,065 $ 1,042,755 $ 42,239 $ 4,631,256 Special mention 6,993 15,984 13,021 14,457 13,597 48,775 21 112,848 Substandard 5,729 4,185 4,690 20,122 15,093 48,127 36 97,982 Doubtful 1 - - - - 5 - 6 Total commercial owner occupied $ 817,915 $ 977,581 $ 739,519 $ 638,364 $ 486,755 $ 1,139,662 $ 42,296 $ 4,842,092 ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial and industrial ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 2,723,320 $ 595,310 $ 450,238 $ 308,914 $ 223,532 $ 419,555 $ 247,169 $ 4,968,038 Special mention 1,566 3,273 3,031 7,243 2,496 25,727 9,368 52,704 Substandard 347 1,070 6,202 7,718 2,808 6,010 2,240 26,395 Doubtful - 2 1 3 3 1 ​ 10 Total commercial and industrial $ 2,725,233 $ 599,655 $ 459,472 $ 323,878 $ 228,839 $ 451,293 $ 258,777 $ 5,047,147 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other income producing property ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 95,530 $ 89,648 $ 75,301 $ 55,103 $ 66,351 $ 121,304 $ 6,487 $ 509,724 Special mention 2,613 1,417 1,702 235 879 11,202 100 18,148 Substandard 1,071 1,046 997 19 1,279 13,702 47 18,161 Doubtful - - - - - 6 - 6 Total other income producing property $ 99,214 $ 92,111 $ 78,000 $ 55,357 $ 68,509 $ 146,214 $ 6,634 $ 546,039 ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer owner occupied ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 7,590 $ 3,527 $ 356 $ 339 $ 1,076 $ 1,290 $ 15,502 $ 29,680 Special mention 130 3,581 249 62 - 124 338 4,484 Substandard 113 387 142 - 5 326 - 973 Doubtful - - - - - - - - Total Consumer owner occupied $ 7,833 $ 7,495 $ 747 $ 401 $ 1,081 $ 1,740 $ 15,840 $ 35,137 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other loans ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 17,993 $ - $ - $ - $ - $ - $ - $ 17,993 Special mention - - - - - - - - Substandard - - - - - - - - Doubtful - - - - - - - - Total other loans $ 17,993 $ - $ - $ - $ - $ - $ - $ 17,993 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Commercial Loans ​ ​ ​ ​ ​ ​ ​ ​ Risk rating: ​ ​ ​ ​ ​ ​ ​ ​ Pass $ 4,906,233 $ 3,138,214 $ 2,226,410 $ 1,708,578 $ 1,466,937 $ 2,834,164 $ 384,920 $ 16,665,456 Special mention 74,706 106,813 130,176 68,544 57,424 224,136 9,827 671,626 Substandard 9,000 59,150 20,291 57,170 58,003 114,943 2,323 320,880 Doubtful 1 2 1 3 3 24 - 34 Total Commercial Loans $ 4,989,940 $ 3,304,179 $ 2,376,878 $ 1,834,295 $ 1,582,367 $ 3,173,267 $ 397,070 $ 17,657,996 ​ For the consumer segment, delinquency of a loan is determined by past due status. Consumer loans are automatically placed on nonaccrual status once the loan is 90 days past due. Construction and land development loans are on 1-4 properties and lots. The following table presents the credit risk profile by past due status of consumer loans by origination year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loans ​ ​ (Dollars in thousands) Amortized Cost Basis by Origination Year ​ ​ As of December 31, 2020 2020 2019 2018 2017 2016 Prior Revolving Total Consumer owner occupied ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 810,215 $ 675,928 $ 543,711 $ 508,160 $ 392,754 $ 1,097,008 $ - $ 4,027,776 30 days past due 4,933 7,744 2,816 2,382 3,510 10,522 - 31,907 60 days past due - 350 1,222 621 103 3,068 - 5,364 90 days past due - 176 264 994 875 5,549 - 7,858 Total Consumer owner occupied $ 815,148 $ 684,198 $ 548,013 $ 512,157 $ 397,242 $ 1,116,147 $ - $ 4,072,905 ​ ​ ​ ​ ​ ​ ​ ​ ​ Home equity loans ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 7,654 $ 6,694 $ 7,670 $ 658 $ 398 $ 30,039 $ 1,276,058 $ 1,329,171 30 days past due 134 52 - 79 - 272 2,324 2,861 60 days past due - - - - - 116 418 534 90 days past due 155 93 - 157 330 1,886 1,502 4,123 Total Home equity loans $ 7,943 $ 6,839 $ 7,670 $ 894 $ 728 $ 32,313 $ 1,280,302 $ 1,336,689 ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 291,305 $ 201,330 $ 115,203 $ 62,485 $ 38,272 $ 147,101 $ 32,874 $ 888,570 30 days past due 105 473 454 224 29 1,043 23 2,351 60 days past due 68 143 93 61 37 376 47 825 90 days past due 73 195 272 185 100 1,663 100 2,588 Total consumer $ 291,551 $ 202,141 $ 116,022 $ 62,955 $ 38,438 $ 150,183 $ 33,044 $ 894,334 ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 370,975 $ 164,260 $ 63,936 $ 18,530 $ 4,497 $ 25,399 $ - $ 647,597 30 days past due 6,172 3,660 161 - 2,255 184 - 12,432 60 days past due 282 - 438 - - - - 720 90 days past due - - - - - 52 - 52 Total Construction and land development $ 377,429 $ 167,920 $ 64,535 $ 18,530 $ 6,752 $ 25,635 $ - $ 660,801 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other income producing property ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 1,412 $ 1,351 $ 1,310 $ 3,658 $ 2,045 $ 31,592 $ - $ 41,368 30 days past due - - - - - 27 - 27 60 days past due - - - - - 13 - 13 90 days past due - - - - - 1 - 1 Total other income producing property $ 1,412 $ 1,351 $ 1,310 $ 3,658 $ 2,045 $ 31,633 $ - $ 41,409 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Consumer Loans ​ ​ ​ ​ ​ ​ ​ ​ Days past due: ​ ​ ​ ​ ​ ​ ​ ​ Current $ 1,481,561 $ 1,049,563 $ 731,830 $ 593,491 $ 437,966 $ 1,331,139 $ 1,308,932 $ 6,934,482 30 days past due 11,344 11,929 3,431 2,685 5,794 12,048 2,347 49,578 60 days past due 350 493 1,753 682 140 3,573 465 7,456 90 days past due 228 464 536 1,336 1,305 9,151 1,602 14,622 Total Consumer Loans $ 1,493,483 $ 1,062,449 $ 737,550 $ 598,194 $ 445,205 $ 1,355,911 $ 1,313,346 $ 7,006,138 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loans ​ ​ (Dollars in thousands) Amortized Cost Basis by Origination Year ​ ​ As of December 31, 2020 2020 2019 2018 2017 2016 Prior Revolving Total Total Loans $ 6,483,423 $ 4,366,628 $ 3,114,428 $ 2,432,489 $ 2,027,572 $ 4,529,178 $ 1,710,416 $ 24,664,134 ​ ​ ​ The following table presents the credit risk profile by risk grade of commercial loans for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction & Development ​ Commercial Non-owner Occupied ​ Commercial Owner Occupied ​ ​ December 31, ​ December 31, ​ December 31, (Dollars in thousands) 2019 2019 2019 Pass ​ $ 959,206 ​ $ 1,787,306 ​ $ 1,754,801 Special mention ​ 7,095 ​ 22,410 ​ 19,742 Substandard ​ 2,059 ​ 1,422 ​ 9,474 Doubtful ​ — ​ — ​ — ​ ​ $ 968,360 ​ $ 1,811,138 ​ $ 1,784,017 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial & Industrial ​ Other Income Producing Property ​ Commercial Total ​ ​ December 31, ​ December 31, ​ December 31, ​ 2019 2019 2019 Pass ​ $ 1,256,465 ​ $ 213,291 ​ $ 5,971,069 ​ Special mention ​ 16,055 ​ 3,966 ​ 69,268 ​ Substandard ​ 8,339 ​ 1,360 ​ 22,654 ​ Doubtful ​ — ​ — ​ — ​ ​ ​ $ 1,280,859 ​ $ 218,617 ​ $ 6,062,991 ​ ​
Summary of information pertaining to nonaccrual loans by class	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ Greater than ​ Non-accrual ​ ​ (Dollars in thousands) 2019 2020 ​ 90 Days Accruing (1) with no allowance (1) Construction and land development ​ $ 1,193 ​ $ 2,421 ​ $ — ​ $ 533 ​ ​ Commercial non-owner occupied ​ 1,154 ​ 4,596 ​ ​ 471 ​ — ​ ​ Commercial owner occupied real estate ​ 4,385 ​ 26,059 ​ ​ — ​ 9,351 ​ ​ Consumer owner occupied ​ 9,718 ​ 30,746 ​ ​ 34 ​ 383 ​ ​ Home equity loans ​ 4,640 ​ 9,944 ​ ​ — ​ 52 ​ ​ Commercial and industrial ​ 6,913 ​ 9,218 ​ ​ 10,864 ​ 585 ​ ​ Other income producing property ​ 1,947 ​ 6,130 ​ ​ 278 ​ 349 ​ ​ Consumer ​ 3,191 ​ 6,074 ​ ​ 4 ​ — ​ ​ Total loans on nonaccrual status ​ $ 33,141 ​ $ 95,188 ​ $ 11,651 ​ $ 11,253 ​ ​ (1)
Summary of collateral dependent loans, by type of collateral	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ Collateral ​ ​ December 31, ​ Collateral ​ ​ (Dollars in thousands) 2019 Coverage % ​ 2020 Coverage % ​ Commercial non-owner occupied ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Church ​ $ 245 ​ $ 846 345% ​ $ — ​ $ — ​ ​ Office ​ ​ 1,045 ​ ​ 1,800 172% ​ ​ — ​ ​ — ​ ​ Other ​ ​ 398 ​ ​ 648 163% ​ ​ — ​ ​ — ​ ​ Retail ​ ​ 299 ​ ​ 1,269 424% ​ ​ — ​ ​ — ​ ​ Commercial owner occupied real estate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Church ​ ​ — ​ ​ — ​ ​ ​ — ​ ​ — ​ ​ Industrial ​ ​ 738 ​ ​ 1,103 149% ​ ​ — ​ ​ — ​ ​ Office ​ ​ 1,076 ​ ​ 1,485 138% ​ ​ 1,076 ​ ​ 1,485 138% ​ Retail ​ ​ — ​ ​ — ​ ​ ​ 4,849 ​ ​ 5,490 113% ​ Other ​ ​ 3,303 ​ ​ 7,285 221% ​ ​ 1,010 ​ ​ 1,075 106% ​ Consumer owner occupied ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 5,413 ​ ​ 9,286 172% ​ ​ — ​ ​ — ​ ​ Home equity loans ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 1,768 ​ ​ 2,679 152% ​ ​ — ​ ​ — ​ ​ Commercial and industrial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Industrial ​ ​ 291 ​ ​ 702 241% ​ ​ — ​ ​ — ​ ​ Other ​ ​ 3,696 ​ ​ 8,442 228% ​ ​ — ​ ​ — ​ ​ Other income producing property ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 3,212 ​ ​ 10,186 317% ​ ​ — ​ ​ — ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ ​ 363 ​ ​ 525 145% ​ ​ — ​ ​ — ​ ​ Total collateral dependent loans ​ $ 21,847 ​ $ 46,256 ​ ​ $ 6,935 ​ $ 8,050 ​ ​
Schedule of restructured loans segregated by class and type of concession	​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2020 ​ ​ ​ ​ Pre-Modification ​ Post-Modification ​ ​ Number ​ Amortized ​ Amortized ​ (Dollars in thousands) of loans ​ Cost ​ Cost ​ Interest rate modification ​ ​ ​ ​ ​ ​ Construction and land development 2 ​ $96 ​ $96 ​ Commercial non-owner occupied -- ​ -- ​ -- ​ Commercial owner occupied 4 ​ 6,905 ​ 6,905 ​ Consumer owner occupied 1 ​ 28 ​ 28 ​ Home equity loans 1 ​ 52 ​ 52 ​ Commercial and industrial 3 ​ 372 ​ 372 ​ Other income producing property 2 ​ 71 ​ 71 ​ Consumer -- ​ -- ​ -- ​ Other loans -- ​ -- ​ -- ​ Total interest rate modifications 13 ​ $7,524 ​ $7,524 ​ Term modification ​ ​ ​ ​ ​ ​ Construction and land development -- ​ $-- ​ $-- ​ Commercial non-owner occupied -- ​ -- ​ -- ​ Commercial owner occupied 1 ​ 180 ​ 180 ​ Consumer owner occupied 5 ​ 579 ​ 579 ​ Home equity loans 1 ​ 50 ​ 50 ​ Commercial and industrial 2 ​ 284 ​ 284 ​ Other income producing property 1 ​ 338 ​ 338 ​ Consumer 3 ​ 120 ​ 120 ​ Other loans -- ​ -- ​ -- ​ Total term modifications 13 ​ $1,551 ​ $1,551 ​ ​ 26 ​ $ 9,075 ​ $ 9,075 ​
Schedule of changes in status of loans restructured within the previous 12 months	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Paying Under ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Restructured Terms ​ Converted to Nonaccrual ​ Foreclosures and Defaults ​ ​ Number ​ Amortized ​ Number ​ Amortized ​ Number ​ Amortized (Dollars in thousands) ​ of Loans ​ Cost ​ of Loans ​ Cost ​ of Loans ​ Cost Interest rate modification ​ 12 ​ $ 7,224 ​ -- ​ $-- ​ 1 ​ $300 Term modification ​ 13 ​ 1,551 ​ -- ​ -- ​ -- ​ -- ​ ​ 25 ​ $ 8,775 ​ -- ​ $-- ​ 1 ​ $300
CSFL
Summary of Loans
Schedule of purchased loans through its acquisition of CSB	​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ June 7, 2020 ​ Book value of acquired loans at acquisition ​ $ 3,091,264 ​ Allowance for credit losses at acquisition ​ (149,404) ​ Non-credit discount at acquisition ​ (14,283) ​ Carrying value or book value of acquired loans at acquisition ​ $ 2,927,577 ​
Schedule of contractual loan payments receivable, estimates of amounts not expected to be collected, other fair value adjustments and the resulting carrying values	​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ June 7, 2020 ​ Book value of acquired loans at acquisition ​ $ 3,091,264 ​ Allowance for credit losses at acquisition ​ (149,404) ​ Non-credit discount at acquisition ​ (14,283) ​ Carrying value or book value of acquired loans at acquisition ​ $ 2,927,577 ​
Non-acquired loans
Summary of Loans
Summary of loans	The following is a summary of non-acquired loans for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Non-acquired loans: ​ ​ ​ Commercial non-owner occupied real estate: ​ ​ ​ ​ Construction and land development ​ $ 968,360 ​ Commercial non-owner occupied ​ 1,811,138 ​ Total commercial non-owner occupied real estate ​ 2,779,498 ​ Consumer real estate: ​ ​ ​ ​ Consumer owner occupied ​ 2,118,839 ​ Home equity loans ​ 518,628 ​ Total consumer real estate ​ 2,637,467 ​ Commercial owner occupied real estate ​ 1,784,017 ​ Commercial and industrial ​ 1,280,859 ​ Other income producing property ​ 218,617 ​ Consumer ​ 538,481 ​ Other loans ​ 13,892 ​ Total non-acquired loans ​ 9,252,831 ​ Less allowance for loan losses ​ (56,927) ​ Non-acquired loans, net ​ $ 9,195,904 ​
Schedule of credit risk profile by risk grade of loans	The following table presents the credit risk profile by risk grade of total non-acquired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ Total Non-acquired Loans ​ ​ December 31, (Dollars in thousands) 2019 Pass ​ $ 9,123,097 Special mention ​ 83,830 Substandard ​ 45,904 Doubtful ​ — ​ ​ $ 9,252,831
Aging analysis of past due loans (includes nonaccrual loans), segregated by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ ​ ​ ​ Total (Dollars in thousands) Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Non-Accruing ​ Loans December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development $ 520 ​ $ 1,142 ​ $ — ​ $ 1,662 ​ $ 1,894,983 ​ $ 2,421 ​ $ 1,899,066 Commercial non-owner occupied 188 ​ 372 ​ 471 ​ 1,031 ​ 5,925,696 ​ 4,596 ​ 5,931,323 Commercial owner occupied 2,900 ​ ​ 840 ​ — ​ 3,740 ​ 4,812,293 ​ 26,059 ​ 4,842,092 Consumer owner occupied 1,375 ​ 3,632 ​ 34 ​ 5,041 ​ 4,072,255 ​ 30,746 ​ 4,108,042 Home equity loans 1,805 ​ 481 ​ — ​ 2,286 ​ 1,324,459 ​ 9,944 ​ 1,336,689 Commercial and industrial 10,979 ​ 22,089 ​ 10,864 ​ 43,932 ​ 4,993,997 ​ 9,218 ​ 5,047,147 Other income producing property 687 ​ — ​ 278 ​ 965 ​ 580,353 ​ 6,130 ​ 587,448 Consumer 1,718 ​ 818 ​ 4 ​ 2,540 ​ 885,720 ​ 6,074 ​ 894,334 Other loans 13 ​ 6 ​ — ​ 19 ​ 17,974 ​ — ​ 17,993 ​ $ 20,185 ​ $ 29,380 ​ $ 11,651 ​ $ 61,216 ​ $ 24,507,730 ​ $ 95,188 ​ $ 24,664,134 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ Total (Dollars in thousands) ​ Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Loans December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development ​ $ 321 ​ $ 39 ​ $ 255 ​ $ 615 ​ $ 967,745 ​ $ 968,360 Commercial non-owner occupied ​ 114 ​ — ​ 299 ​ 413 ​ 1,810,725 ​ 1,811,138 Commercial owner occupied ​ 4,011 ​ 636 ​ 2,302 ​ 6,949 ​ 1,777,068 ​ 1,784,017 Consumer real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer owner occupied ​ 1,157 ​ 285 ​ 2,424 ​ 3,866 ​ 2,114,973 ​ 2,118,839 Home equity loans ​ 1,343 ​ 39 ​ 562 ​ 1,944 ​ 516,684 ​ 518,628 Commercial and industrial ​ 5,531 ​ 100 ​ 649 ​ 6,280 ​ 1,274,579 ​ 1,280,859 Other income producing property ​ 208 ​ — ​ 457 ​ 665 ​ 217,952 ​ 218,617 Consumer ​ 825 ​ 285 ​ 826 ​ 1,936 ​ 536,545 ​ 538,481 Other loans ​ 25 ​ 3 ​ — ​ 28 ​ 13,864 ​ 13,892 ​ ​ $ 13,535 ​ $ 1,387 ​ $ 7,774 ​ $ 22,696 ​ $ 9,230,135 ​ $ 9,252,831
Non-acquired loans | Consumer
Summary of Loans
Schedule of credit risk profile by risk grade of loans	The following table presents the credit risk profile by risk grade of consumer loans for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer Owner Occupied ​ Home Equity ​ Consumer ​ ​ December 31, ​ December 31, ​ December 31, (Dollars in thousands) 2019 2019 2019 Pass ​ $ 2,094,080 ​ $ 508,054 ​ $ 536,002 Special mention ​ 9,585 ​ 4,490 ​ 487 Substandard ​ 15,174 ​ 6,084 ​ 1,992 Doubtful ​ — ​ — ​ — ​ ​ $ 2,118,839 ​ $ 518,628 ​ $ 538,481 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ Consumer Total ​ December 31, 2019 December 31, 2019 Pass ​ $ 13,892 ​ $ 3,152,028 Special mention ​ — ​ 14,562 Substandard ​ — ​ 23,250 Doubtful ​ — ​ — ​ ​ $ 13,892 ​ $ 3,189,840
Acquired credit impaired loans
Summary of Loans
Summary of loans	​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Acquired credit impaired loans: ​ ​ ​ Commercial real estate ​ $ 130,938 ​ Commercial real estate—construction and development ​ 25,032 ​ Residential real estate ​ 163,359 ​ Consumer ​ 35,488 ​ Commercial and industrial ​ 7,029 ​ Acquired credit impaired loans ​ 361,846 ​ Less allowance for loan losses ​ (5,064) ​ Acquired credit impaired loans, net ​ $ 356,782 ​
Schedule of purchased loans through its acquisition of CSB	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ Contractual principal and interest ​ ​ $ 452,818 Non-accretable difference ​ ​ (13,938) ​ Cash flows expected to be collected ​ ​ 438,880 ​ Accretable yield ​ ​ (82,098) ​ Carrying value ​ ​ $ 356,782 ​
Schedule of contractual loan payments receivable, estimates of amounts not expected to be collected, other fair value adjustments and the resulting carrying values	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ Contractual principal and interest ​ ​ $ 452,818 Non-accretable difference ​ ​ (13,938) ​ Cash flows expected to be collected ​ ​ 438,880 ​ Accretable yield ​ ​ (82,098) ​ Carrying value ​ ​ $ 356,782 ​
Schedule of changes in the carrying value	​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2019 Balance at beginning of period ​ $ 485,119 ​ Net reductions for payments, foreclosures, and accretion ​ (127,877) ​ Change in the allowance for loan losses on acquired loans ​ (460) ​ Balance at end of period, net of allowance for loan losses on acquired credit impaired loans ​ $ 356,782 ​
Schedule of refined accretable yield balance	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2019 2018 Balance at beginning of period ​ $ 116,754 ​ $ 133,096 ​ Addition from the PSC acquisition ​ ​ — ​ ​ — ​ Park Sterling Corporation ("Park Sterling") acquisition Day 1 adjustment ​ ​ — ​ ​ (1,460) ​ Contractual interest income ​ (26,515) ​ (33,115) ​ Accretion on acquired credit impaired loans ​ ​ (17,813) ​ ​ (19,004) ​ Reclass of nonaccretable difference due to improvement in expected cash flows ​ 9,826 ​ 37,501 ​ Other changes, net ​ (154) ​ (264) ​ Balance at end of period ​ $ 82,098 ​ $ 116,754 ​
Schedule of credit risk profile by risk grade of loans	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 for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial Real Estate— ​ ​ ​ ​ Construction and ​ Commercial Real Estate ​ Development ​ ​ December 31, ​ ​ December 31, (Dollars in thousands) 2019 ​ 2019 Pass ​ $ 108,762 $ 17,756 ​ Special mention ​ 6,465 ​ 2,904 ​ Substandard ​ 15,711 ​ 4,372 ​ Doubtful ​ — ​ — ​ ​ ​ $ 130,938 ​ $ 25,032 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Residential Real Estate ​ Consumer ​ Commercial & Industrial ​ December 31, ​ December 31, ​ December 31, ​ 2019 2019 2019 Pass $ 82,203 ​ $ 4,483 ​ $ 5,160 ​ Special mention 35,968 ​ 12,658 ​ 286 ​ Substandard 45,188 ​ 18,347 ​ 1,583 ​ Doubtful — ​ — ​ — ​ ​ $ 163,359 ​ $ 35,488 ​ $ 7,029 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Acquired ​ ​ ​ Credit Impaired Loans ​ ​ ​ ​ December 31, ​ ​ 2019 Pass ​ $ 218,364 ​ Special mention ​ ​ 58,281 ​ Substandard ​ ​ 85,201 ​ Doubtful ​ ​ — ​ ​ ​ ​ $ 361,846 ​
Aging analysis of past due loans (includes nonaccrual loans), segregated by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ Total (Dollars in thousands) ​ Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Loans December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial real estate ​ $ 2,283 ​ $ — ​ $ 2,659 ​ $ 4,942 ​ $ 125,996 ​ $ 130,938 Commercial real estate—construction and development ​ — ​ — ​ 393 ​ 393 ​ 24,639 ​ 25,032 Residential real estate ​ 2,838 ​ 976 ​ 5,571 ​ 9,385 ​ 153,974 ​ 163,359 Consumer ​ 820 ​ 283 ​ 534 ​ 1,637 ​ 33,851 ​ 35,488 Commercial and industrial ​ 118 ​ 910 ​ 75 ​ 1,103 ​ 5,926 ​ 7,029 ​ ​ $ 6,059 ​ $ 2,169 ​ $ 9,232 ​ $ 17,460 ​ $ 344,386 ​ $ 361,846
Non acquired non-accrual loans
Summary of Loans
Summary of information pertaining to nonaccrual loans by class	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Commercial non-owner occupied real estate: ​ ​ ​ ​ ​ Construction and land development ​ ​ $ 363 ​ Commercial non-owner occupied ​ ​ 732 ​ Total commercial non-owner occupied real estate ​ ​ 1,095 ​ Consumer real estate: ​ ​ ​ ​ ​ Consumer owner occupied ​ ​ 7,202 ​ Home equity loans ​ ​ 1,468 ​ Total consumer real estate ​ ​ 8,670 ​ Commercial owner occupied real estate ​ ​ 3,482 ​ Commercial and industrial ​ ​ 4,092 ​ Other income producing property ​ ​ 798 ​ Consumer ​ ​ 1,587 ​ Restructured loans ​ ​ 2,578 ​ Total loans on nonaccrual status ​ ​ $ 22,302 ​
Acquired non-credit impaired non-accrual loans
Summary of Loans
Summary of information pertaining to nonaccrual loans by class	​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Commercial non-owner occupied real estate: ​ ​ ​ Construction and land development ​ $ 699 Commercial non-owner occupied ​ ​ 393 Total commercial non-owner occupied real estate ​ ​ 1,092 Consumer real estate: ​ ​ ​ Consumer owner occupied ​ ​ 2,350 Home equity loans ​ ​ 3,067 Total consumer real estate ​ ​ 5,417 Commercial owner occupied real estate ​ ​ 903 Commercial and industrial ​ ​ 722 Other income producing property ​ ​ 1,101 Consumer ​ ​ 1,604 Total loans on nonaccrual status ​ $ 10,839
Acquired non-credit impaired loans
Summary of Loans
Summary of loans	The following is a summary of acquired non-credit impaired loans accounted for under FASB ASC Topic 310-20, net of related discount, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2019 Acquired non-credit impaired loans: ​ ​ ​ Commercial non-owner occupied real estate: ​ ​ ​ ​ Construction and land development ​ $ 33,569 ​ Commercial non-owner occupied ​ 447,441 ​ Total commercial non-owner occupied real estate ​ 481,010 ​ Consumer real estate: ​ ​ ​ ​ Consumer owner occupied ​ 496,431 ​ Home equity loans ​ 188,732 ​ Total consumer real estate ​ 685,163 ​ Commercial owner occupied real estate ​ 307,193 ​ Commercial and industrial ​ 101,880 ​ Other income producing property ​ 95,697 ​ Consumer ​ 89,484 ​ Acquired non-credit impaired loans ​ $ 1,760,427 ​
Schedule of credit risk profile by risk grade of loans	​ The following table presents the credit risk profile by risk grade of total acquired non-credit impaired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ Total Acquired ​ ​ ​ Non-credit Impaired Loans ​ ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ Pass ​ $ 1,697,942 Special mention ​ 39,772 ​ Substandard ​ 22,713 ​ Doubtful ​ — ​ ​ ​ $ 1,760,427 ​
Aging analysis of past due loans (includes nonaccrual loans), segregated by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 Days 60 - 89 Days 90+ Days Total ​ ​ Total (Dollars in thousands) ​ Past Due ​ Past Due ​ Past Due ​ Past Due ​ Current ​ Loans December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction and land development ​ $ 20 ​ $ — ​ $ 256 ​ $ 276 ​ $ 33,293 ​ $ 33,569 Commercial non-owner occupied ​ 144 ​ 1,146 ​ 76 ​ 1,366 ​ 446,075 ​ 447,441 Commercial owner occupied ​ 890 ​ 702 ​ 698 ​ 2,290 ​ 304,903 ​ 307,193 Consumer real estate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer owner occupied ​ 768 ​ 151 ​ 414 ​ 1,333 ​ 495,098 ​ 496,431 Home equity loans ​ 369 ​ 55 ​ 1,154 ​ 1,578 ​ 187,154 ​ 188,732 Commercial and industrial ​ 93 ​ 204 ​ 17 ​ 314 ​ 101,566 ​ 101,880 Other income producing property ​ 378 ​ 4,309 ​ 551 ​ 5,238 ​ 90,459 ​ 95,697 Consumer ​ 485 ​ 613 ​ 423 ​ 1,521 ​ 87,963 ​ 89,484 ​ ​ $ 3,147 ​ $ 7,180 ​ $ 3,589 ​ $ 13,916 ​ $ 1,746,511 ​ $ 1,760,427
Acquired non-credit impaired loans | Commercial non-owner occupied real estate
Summary of Loans
Schedule of credit risk profile by risk grade of loans	​ The following table presents the credit risk profile by risk grade of commercial loans for acquired non-credit impaired loans for comparative periods, prior to the adoption of ASU 2016-13, under the incurred loss model: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction & Development ​ ​ Commercial Non-owner Occupied ​ ​ Commercial Owner Occupied ​ ​ December 31, ​ ​ December 31, ​ ​ December 31, ​ (Dollars in thousands) 2019 ​ 2019 ​ 2019 Pass ​ $ 31,690 ​ $ 432,710 $ 300,678 ​ Special mention ​ 966 ​ 14,162 ​ 3,092 ​ Substandard ​ 913 ​ 569 ​ 3,423 ​ Doubtful ​ — ​ — ​ — ​ ​ ​ $ 33,569 ​ $ 447,441 ​ $ 307,193 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other Income Producing ​ ​ ​ ​ ​ ​ Commercial & Industrial ​ Property ​ Commercial Total ​ ​ December 31, ​ ​ December 31, ​ December 31, ​ 2019 ​ 2019 ​ 2019 Pass ​ $ 97,092 $ 87,892 $ 950,062 Special mention ​ 2,948 ​ 5,837 ​ 27,005 Substandard ​ 1,840 ​ 1,968 ​ 8,713 Doubtful ​ — ​ — ​ — ​ ​ $ 101,880 ​ $ 95,697 ​ $ 985,780 ​
Acquired non-credit impaired loans | Consumer
Summary of Loans
Schedule of credit risk profile by risk grade of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer Owner Occupied ​ Home Equity ​ ​ Consumer ​ ​ December 31, ​ December 31, ​ ​ December 31, (Dollars in thousands) ​ 2019 ​ 2019 ​ ​ 2019 Pass $ 486,433 $ 174,912 $ 86,535 Special mention ​ 6,434 ​ 5,679 ​ ​ 654 Substandard ​ 3,564 ​ 8,141 ​ ​ 2,295 Doubtful ​ — ​ — ​ ​ — ​ ​ $ 496,431 ​ $ 188,732 ​ ​ $ 89,484 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer Total ​ ​ ​ December 31, (Dollars in thousands) ​ ​ 2019 Pass ​ $ 747,880 Special mention ​ ​ 12,767 Substandard ​ ​ 14,000 Doubtful ​ ​ — ​ ​ ​ $ 774,647 ​

Allowance for Credit Losses (_2

Allowance for Credit Losses (ACL) (Tables)	12 Months Ended
	Dec. 31, 2020
Allowance for Credit Losses
Schedule of changes in allowance for loan losses	The following table presents a disaggregated analysis of activity in the allowance for credit losses as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Residential ​ Residential ​ ​ ​ Residential ​ Other ​ ​ ​ ​ ​ ​ ​ CRE Owner ​ Non Owner ​ ​ ​ ​ ​ (Dollars in thousands) ​ Mortgage Sr. ​ Mortgage Jr. ​ HELOC ​ Construction ​ C&D ​ Consumer ​ Multifamily ​ Municipal ​ Occupied ​ Occupied CRE ​ C & I (2) ​ Total Year Ended December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for credit losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period January 1, 2020 ​ $ 6,128 ​ $ 15 ​ $ 4,327 ​ $ 815 ​ $ 6,211 ​ $ 4,350 ​ $ 1,557 ​ $ 956 ​ $ 10,879 ​ $ 15,219 ​ $ 6,470 ​ $ 56,927 Impact of Adoption ​ ​ 5,455 ​ ​ 11 ​ ​ 3,849 ​ ​ 779 ​ ​ 5,588 ​ ​ 3,490 ​ ​ 1,391 ​ ​ 914 ​ ​ 9,505 ​ ​ 13,898 ​ ​ 6,150 ​ ​ 51,030 Initial PCD Allowance ​ ​ 406 ​ ​ 3 ​ ​ 289 ​ ​ — ​ ​ 351 ​ ​ 669 ​ ​ 97 ​ ​ — ​ ​ 898 ​ ​ 656 ​ ​ 39 ​ ​ 3,408 Adjusted CECL balance, January 1, 2020 ​ $ 11,989 ​ $ 29 ​ $ 8,465 ​ $ 1,594 ​ $ 12,150 ​ $ 8,509 ​ $ 3,045 ​ $ 1,870 ​ $ 21,282 ​ $ 29,773 ​ $ 12,659 ​ $ 111,365 Impact of merger on provision for non-PCD loans ​ ​ 16,712 ​ ​ 226 ​ ​ 4,227 ​ ​ 4,893 ​ ​ 7,673 ​ ​ 3,836 ​ ​ 1,212 ​ ​ 919 ​ ​ 25,393 ​ ​ 35,067 ​ ​ 9,284 ​ ​ 109,442 Initial PCD Allowance ​ ​ 29,935 ​ ​ 804 ​ ​ 5,119 ​ ​ 1,302 ​ ​ 6,035 ​ ​ 6,120 ​ ​ 902 ​ ​ 1,003 ​ ​ 34,077 ​ ​ 45,787 ​ ​ 18,320 ​ ​ 149,404 Charge-offs ​ (528) ​ (24) ​ (1,053) ​ (32) ​ (347) ​ (6,158) ​ — ​ — ​ (1,205) ​ ​ (601) ​ ​ (4,654) ​ (14,602) Recoveries ​ 1,143 ​ 455 ​ 1,251 ​ 111 ​ 1,407 ​ 1,922 ​ 71 ​ — ​ 1,089 ​ ​ 518 ​ ​ 3,810 ​ 11,777 Net charge offs ​ ​ 615 ​ ​ 431 ​ ​ 198 ​ ​ 79 ​ ​ 1,060 ​ ​ (4,236) ​ ​ 71 ​ ​ — ​ ​ (116) ​ ​ (83) ​ ​ (844) ​ ​ (2,825) Provision (benefit) (1) ​ 4,310 ​ (252) ​ (1,311) ​ (2,954) ​ 40,279 ​ 12,333 ​ 2,657 ​ (2,282) ​ 16,468 ​ ​ 13,877 ​ ​ 6,798 ​ 89,923 Balance at end of period December 31, 2020 ​ $ 63,561 ​ $ 1,238 ​ $ 16,698 ​ $ 4,914 ​ $ 67,197 ​ $ 26,562 ​ $ 7,887 ​ $ 1,510 ​ $ 97,104 ​ $ 124,421 ​ $ 46,217 ​ $ 457,309 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ -1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for credit losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quantitative allowance ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collectively evaluated ​ $ 54,656 ​ $ 1,238 ​ $ 14,625 ​ $ 4,733 ​ $ 67,188 ​ $ 18,435 ​ $ 7,887 ​ $ 685 ​ $ 91,106 ​ $ 116,571 ​ $ 38,805 ​ $ 415,929 Individually evaluated ​ ​ 82 ​ ​ — ​ ​ 77 ​ ​ — ​ ​ 9 ​ ​ 120 ​ ​ — ​ ​ — ​ ​ 948 ​ ​ 6 ​ ​ 7 ​ ​ 1,249 Total quantitative allowance ​ ​ 54,738 ​ ​ 1,238 ​ ​ 14,702 ​ ​ 4,733 ​ ​ 67,197 ​ ​ 18,555 ​ ​ 7,887 ​ ​ 685 ​ ​ 92,054 ​ ​ 116,577 ​ ​ 38,812 ​ ​ 417,178 Qualitative allowance ​ ​ 8,823 ​ ​ — ​ ​ 1,996 ​ ​ 181 ​ ​ — ​ ​ 8,007 ​ ​ — ​ ​ 825 ​ ​ 5,050 ​ ​ 7,844 ​ ​ 7,405 ​ ​ 40,131 Balance at end of period December 31, 2020 ​ $ 63,561 ​ $ 1,238 ​ $ 16,698 ​ $ 4,914 ​ $ 67,197 ​ $ 26,562 ​ $ 7,887 ​ $ 1,510 ​ $ 97,104 ​ $ 124,421 ​ $ 46,217 ​ $ 457,309 ​ (1) – Additional provision for credit losses of $43.4 million was recorded during 2020 for the allowance for credit losses for unfunded commitments that is not considered in the above table. Of this amount, $9.6 million was from the initial impact from the merger with CSFL. (2) – The ACL for the C&I segment does not include reserve for PPP loans, which are government guaranteed. ​ ​ An aggregated analysis of the changes in allowance for loan losses, for comparative periods, prior to the adoption of ASU 2016-13 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-acquired Acquired Acquired Credit ​ ​ (Dollars in thousands) ​ Loans ​ Impaired Loans ​ Impaired Loans ​ Total Year Ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 51,194 ​ $ — ​ $ 4,604 ​ $ 55,798 Loans charged-off ​ (6,917) ​ ​ (2,858) ​ — ​ (9,775) Recoveries of loans previously charged off ​ 3,367 ​ ​ 547 ​ — ​ 3,914 Net charge-offs ​ (3,550) ​ ​ (2,311) ​ — ​ (5,861) Provision for loan losses charged to operations ​ 9,283 ​ ​ 2,311 ​ 1,183 ​ 12,777 Reduction due to loan removals ​ — ​ ​ — ​ (723) ​ (723) Balance at end of period ​ $ 56,927 ​ $ — ​ $ 5,064 ​ $ 61,991 Year Ended December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 43,448 ​ $ — ​ $ 4,627 ​ $ 48,075 Loans charged-off ​ (6,012) ​ ​ (2,214) ​ — ​ (8,226) Recoveries of loans previously charged off ​ 2,995 ​ ​ 305 ​ — ​ 3,300 Net charge-offs ​ (3,017) ​ ​ (1,909) ​ — ​ (4,926) Provision for loan losses charged to operations ​ 10,763 ​ ​ 1,909 ​ 1,111 ​ 13,783 Reduction due to loan removals ​ — ​ ​ — ​ (1,134) ​ (1,134) Balance at end of period ​ $ 51,194 ​ $ — ​ $ 4,604 ​ $ 55,798
Non-acquired loans
Allowance for Credit Losses
Schedule of changes in allowance for loan losses	​ The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for non-acquired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 Year Ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 5,682 ​ $ 8,754 ​ $ 9,369 ​ $ 11,913 ​ $ 3,434 ​ $ 7,454 ​ $ 1,446 ​ $ 3,101 ​ $ 41 ​ $ 51,194 ​ Charge-offs ​ (78) ​ (3) ​ (87) ​ (50) ​ (203) ​ (622) ​ (31) ​ (5,843) ​ — ​ (6,917) ​ Recoveries ​ 1,016 ​ 76 ​ 174 ​ 213 ​ 265 ​ 351 ​ 94 ​ 1,178 ​ — ​ 3,367 ​ Provision (benefit) ​ (516) ​ 1,872 ​ 1,125 ​ 520 ​ (308) ​ 1,156 ​ (173) ​ 5,511 ​ 96 ​ 9,283 ​ Balance at end of period ​ $ 6,104 ​ $ 10,699 ​ $ 10,581 ​ $ 12,596 ​ $ 3,188 ​ $ 8,339 ​ $ 1,336 ​ $ 3,947 ​ $ 137 ​ $ 56,927 ​ Loans individually evaluated for impairment ​ $ 617 ​ $ — ​ $ 24 ​ $ 102 ​ $ 132 ​ $ 366 ​ $ 50 ​ $ 55 ​ $ — ​ $ 1,346 ​ Loans collectively evaluated for impairment ​ $ 5,487 ​ $ 10,699 ​ $ 10,557 ​ $ 12,494 ​ $ 3,056 ​ $ 7,973 ​ $ 1,286 ​ $ 3,892 ​ $ 137 ​ $ 55,581 ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ 35,201 ​ $ 379 ​ $ 6,575 ​ $ 5,141 ​ $ 2,461 ​ $ 6,578 ​ $ 2,024 ​ $ 173 ​ $ — ​ $ 58,532 ​ Loans collectively evaluated for impairment ​ 933,159 ​ 1,810,759 ​ 1,777,442 ​ 2,113,698 ​ 516,167 ​ 1,274,281 ​ 216,593 ​ 538,308 ​ 13,892 ​ 9,194,299 ​ Total non-acquired loans ​ $ 968,360 ​ $ 1,811,138 ​ $ 1,784,017 ​ $ 2,118,839 ​ $ 518,628 ​ $ 1,280,859 ​ $ 218,617 ​ $ 538,481 ​ $ 13,892 ​ $ 9,252,831 ​ Year Ended December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ 5,921 ​ $ 6,525 ​ $ 8,128 ​ $ 9,668 ​ $ 3,250 ​ $ 5,488 ​ $ 1,375 ​ $ 2,788 ​ $ 305 ​ $ 43,448 ​ Charge-offs ​ (76) ​ — ​ (659) ​ (80) ​ (215) ​ (500) ​ (2) ​ (4,480) ​ — ​ (6,012) ​ Recoveries ​ 1,340 ​ 11 ​ 145 ​ 132 ​ 279 ​ 256 ​ 21 ​ 811 ​ — ​ 2,995 ​ Provision (benefit) ​ (1,503) ​ 2,218 ​ 1,755 ​ 2,193 ​ 120 ​ 2,210 ​ 52 ​ 3,982 ​ (264) ​ 10,763 ​ Balance at end of period ​ $ 5,682 ​ $ 8,754 ​ $ 9,369 ​ $ 11,913 ​ $ 3,434 ​ $ 7,454 ​ $ 1,446 ​ $ 3,101 ​ $ 41 ​ $ 51,194 ​ Loans individually evaluated for impairment ​ $ 788 ​ $ 70 ​ $ 27 ​ $ 41 ​ $ 142 ​ $ 416 ​ $ 142 ​ $ 2 ​ $ — ​ $ 1,628 ​ Loans collectively evaluated for impairment ​ $ 4,894 ​ $ 8,684 ​ $ 9,342 ​ $ 11,872 ​ $ 3,292 ​ $ 7,038 ​ $ 1,304 ​ $ 3,099 ​ $ 41 ​ $ 49,566 ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ 37,913 ​ $ 1,025 ​ $ 4,142 ​ $ 6,761 ​ $ 2,826 ​ $ 1,291 ​ $ 2,872 ​ $ 188 ​ $ — ​ $ 57,018 ​ Loans collectively evaluated for impairment ​ 803,532 ​ 1,414,526 ​ 1,513,409 ​ 1,929,504 ​ 492,322 ​ 1,053,661 ​ 211,481 ​ 448,476 ​ 9,357 ​ 7,876,268 ​ Total non-acquired loans ​ $ 841,445 ​ $ 1,415,551 ​ $ 1,517,551 ​ $ 1,936,265 ​ $ 495,148 ​ $ 1,054,952 ​ $ 214,353 ​ $ 448,664 ​ $ 9,357 ​ $ 7,933,286 ​
Acquired non-credit impaired loans
Allowance for Credit Losses
Schedule of changes in allowance for loan losses	​ The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for acquired non-credit impaired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 Year Ended December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Charge-offs ​ (44) ​ — ​ (786) ​ (6) ​ (263) ​ (1,289) ​ (26) ​ (444) ​ (2,858) ​ Recoveries ​ 3 ​ — ​ — ​ 26 ​ 206 ​ 190 ​ 71 ​ 51 ​ 547 ​ Provision (benefit) ​ 41 ​ — ​ 786 ​ (20) ​ 57 ​ 1,099 ​ (45) ​ 393 ​ 2,311 ​ Balance, December 31, 2019 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 33,569 ​ 447,441 ​ 307,193 ​ 496,431 ​ 188,732 ​ 101,880 ​ 95,697 ​ 89,484 ​ 1,760,427 ​ Total acquired non-credit impaired loans ​ $ 33,569 ​ $ 447,441 ​ $ 307,193 ​ $ 496,431 ​ $ 188,732 ​ $ 101,880 ​ $ 95,697 ​ $ 89,484 ​ $ 1,760,427 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2018 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at beginning of period ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Charge-offs ​ (107) ​ — ​ (28) ​ (70) ​ (436) ​ (1,108) ​ — ​ (465) ​ (2,214) ​ Recoveries ​ 8 ​ — ​ — ​ 64 ​ 102 ​ 63 ​ — ​ 68 ​ 305 ​ Provision (benefit) ​ 99 ​ — ​ 28 ​ 6 ​ 334 ​ 1,045 ​ — ​ 397 ​ 1,909 ​ Balance, December 31, 2019 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 165,070 ​ 679,253 ​ 421,841 ​ 628,813 ​ 242,425 ​ 212,537 ​ 133,110 ​ 111,777 ​ 2,594,826 ​ Total acquired non-credit impaired loans ​ $ 165,070 ​ $ 679,253 ​ $ 421,841 ​ $ 628,813 ​ $ 242,425 ​ $ 212,537 ​ $ 133,110 ​ $ 111,777 ​ $ 2,594,826 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Acquired credit impaired loans
Allowance for Credit Losses
Schedule of changes in allowance for loan losses	The following tables present a disaggregated analysis of activity in the allowance for loan losses and loan balances for acquired credit impaired loans, for comparative periods, prior to the adoption of ASU 2016-13: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Estate- ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ Construction and ​ Residential ​ ​ ​ ​ Commercial ​ ​ ​ (Dollars in thousands) ​ Real Estate ​ Development ​ Real Estate ​ Consumer ​ and Industrial ​ Total Year Ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, December 31, 2018 ​ $ 801 ​ $ 717 ​ $ 2,246 ​ $ 761 ​ $ 79 ​ $ 4,604 ​ Provision for loan losses ​ 577 ​ (148) ​ 716 ​ (222) ​ 260 ​ 1,183 ​ Reduction due to loan removals ​ (1) ​ — ​ (407) ​ — ​ (315) ​ (723) ​ Balance, December 31, 2019 ​ $ 1,377 ​ $ 569 ​ $ 2,555 ​ $ 539 ​ $ 24 ​ $ 5,064 ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ 1,377 ​ $ 569 ​ $ 2,555 ​ $ 539 ​ $ 24 ​ $ 5,064 ​ Loans:* ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 130,938 ​ 25,032 ​ 163,359 ​ 35,488 ​ 7,029 ​ 361,846 ​ Total acquired credit impaired loans ​ $ 130,938 ​ $ 25,032 ​ $ 163,359 ​ $ 35,488 ​ $ 7,029 ​ $ 361,846 ​ Year Ended December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, December 31, 2017 ​ $ 288 ​ $ 180 ​ $ 3,553 ​ $ 461 ​ $ 145 ​ $ 4,627 ​ Provision for loan losses ​ 532 ​ 657 ​ (892) ​ 303 ​ 511 ​ 1,111 ​ Reduction due to loan removals ​ (19) ​ (120) ​ (415) ​ (3) ​ (577) ​ (1,134) ​ Balance, December 31, 2018 ​ $ 801 ​ $ 717 ​ $ 2,246 ​ $ 761 ​ $ 79 ​ $ 4,604 ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ $ 801 ​ $ 717 ​ $ 2,246 ​ $ 761 ​ $ 79 ​ $ 4,604 ​ Loans:* ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Loans collectively evaluated for impairment ​ 196,764 ​ 32,942 ​ 207,482 ​ 42,492 ​ 10,043 ​ 489,723 ​ Total acquired credit impaired loans ​ $ 196,764 ​ $ 32,942 ​ $ 207,482 ​ $ 42,492 ​ $ 10,043 ​ $ 489,723 ​ * 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.

Other Real Estate Owned and B_2

Other Real Estate Owned and Bank Premises Held for Sale (Tables)	12 Months Ended
	Dec. 31, 2020
Other Real Estate Owned and Bank Premises Held for Sale
Schedule of information pertaining to OREO and Bank Premises Held for Sale	​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ OREO and Bank Premises ​ Balance, December 31, 2017 ​ $ 11,203 ​ Acquired in Park Sterling Corp. acquisition ​ 210 ​ Additions, net ​ 13,391 ​ Writedowns ​ (1,420) ​ Sold ​ (11,974) ​ Balance, December 31, 2018 ​ 11,410 ​ Other Real Estate Owned at December 31, 2018 ​ ​ 6,153 ​ Bank Premises Held for Sale at December 31, 2018 ​ ​ 5,257 ​ Additions, net ​ ​ 10,373 ​ Writedowns ​ ​ (1,192) ​ Sold ​ ​ (8,627) ​ Balance, December 31, 2019 ​ ​ 11,964 ​ Other Real Estate Owned at December 31, 2019 ​ ​ 6,539 ​ Bank Premises Held for Sale at December 31, 2019 ​ ​ 5,425 ​ Acquired in the CSFL acquisition ​ ​ 28,311 ​ Additions, net ​ ​ 27,340 ​ Writedowns ​ ​ (1,085) ​ Sold ​ ​ (18,610) ​ Balance, December 31, 2020 ​ ​ 47,920 ​ Other Real Estate Owned at December 31, 2020 ​ ​ 11,914 ​ Bank Premises Held for Sale at December 31, 2020 ​ $ 36,006 ​

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
Premises and Equipment
Schedule of premises and equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ Useful Life ​ 2020 ​ 2019 Land ​ ​ ​ $ 152,263 $ 74,913 ​ Buildings and leasehold improvements 15 - 40 years ​ 406,078 ​ 226,750 ​ Equipment and furnishings 3 - 10 years ​ 161,009 ​ ​ 106,696 ​ Lease right of use assets ​ ​ ​ ​ ​ ​ ​ 113,422 ​ ​ 87,389 ​ Construction in process ​ ​ ​ ​ ​ ​ 3,618 ​ 1,977 ​ Total ​ ​ ​ ​ ​ ​ 836,390 ​ 497,725 ​ Less accumulated depreciation ​ ​ ​ ​ ​ ​ (257,151) ​ (180,404) ​ ​ ​ ​ ​ ​ ​ ​ $ 579,239 ​ $ 317,321 ​

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Other Intangible Assets
Summary of changes in the carrying amounts of goodwill	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Balance at beginning of period $ 1,002,900 $ 1,002,900 ​ Additions: ​ ​ ​ ​ ​ ​ ​ Goodwill from CenterState acquisition ​ 561,042 ​ ​ — ​ Balance at end of period ​ $ 1,563,942 ​ $ 1,002,900 ​
Summary of gross carrying amounts and accumulated amortization of other intangible assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Gross carrying amount ​ $ 258,554 $ 119,501 ​ Accumulated amortization ​ ​ (95,962) ​ (69,685) ​ ​ ​ ​ $ 162,592 ​ $ 49,816 ​
Schedule of estimated amortization expense of intangibles assets	​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ Year ended December 31: ​ ​ 2021 ​ $ 33,845 ​ 2022 ​ 30,056 ​ 2023 ​ 24,634 ​ 2024 ​ 19,790 ​ 2025 ​ 16,480 ​ Thereafter ​ 37,787 ​ ​ ​ $ 162,592 ​ ​ ​ ​ ​ ​

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2020
Deposits
Schedule of total deposits	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Certificates of deposit ​ ​ $ 3,743,271 $ 1,651,399 ​ Interest-bearing demand deposits ​ ​ 14,539,928 ​ 5,966,496 ​ Non-interest bearing demand deposits ​ ​ 9,711,338 ​ 3,245,306 ​ Savings deposits ​ ​ 2,694,011 ​ 1,309,896 ​ Other time deposits ​ ​ 5,334 ​ 3,999 ​ Total deposits ​ ​ $ 30,693,882 ​ $ 12,177,096 ​
Schedule of maturities of time deposits of all denominations	​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Year ended December 31: ​ ​ ​ ​ 2021 ​ $ 2,704,310 ​ 2022 ​ 610,282 ​ 2023 ​ 210,321 ​ 2024 ​ 97,640 ​ 2025 ​ 123,218 ​ Thereafter ​ 2,834 ​ ​ ​ $ 3,748,605 ​

Federal Funds Purchased and S_2

Federal Funds Purchased and Securities Sold Under Agreements to Repurchase (Tables)	12 Months Ended
	Dec. 31, 2020
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
Schedule of information concerning federal funds purchased and securities sold under agreements to repurchase	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2020 ​ 2019 ​ 2018 (Dollars in thousands) ​ Amount ​ Rate ​ Amount ​ Rate ​ Amount ​ Rate At period-end: ​ ​ ​ ​ Federal funds purchased and securities sold under repurchase agreements ​ $ 779,666 0.17 % $ 298,741 0.90 % $ 270,649 1.08 % Average for the year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal funds purchased and securities sold under repurchase agreements ​ $ 553,110 0.35 % $ 282,172 0.93 % $ 312,768 0.75 % Maximum month-end balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal funds purchased and securities sold under repurchase agreements ​ $ 779,666 ​ ​ ​ $ 321,833 ​ ​ ​ $ 362,047 ​ ​ ​

Other Borrowings (Tables)

Other Borrowings (Tables)	12 Months Ended
	Dec. 31, 2020
Other Borrowings.
Schedule of other borrowings	The Company’s other borrowings were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2020 ​ ​ ​ 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ Interest ​ ​ ​ ​ ​ ​ Average ​ Interest ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Rate at ​ ​ ​ Average ​ Interest ​ Rate at ​ ​ ​ Average ​ Interest ​ (Dollars in thousands) Maturity 12/31/2020 Balance ​ Balance Rate 12/31/2019 Balance ​ Balance Rate ​ Short-term borrowings: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal Home Loan Bank Fixed Rate Credit ​ 3/4/2020 ​ — % $ — ​ ​ ​ ​ ​ ​ 1.75 % $ 200,000 ​ ​ ​ ​ ​ ​ Federal Home Loan Bank Fixed Rate Credit ​ 3/19/2020 ​ — % ​ — ​ ​ ​ ​ ​ ​ 1.73 % ​ 350,000 ​ ​ ​ ​ ​ ​ Federal Home Loan Bank Fixed Rate Credit ​ 3/30/2020 ​ — % — ​ ​ ​ ​ ​ ​ 1.72 % 150,000 ​ ​ ​ ​ ​ ​ Total short-term borrowings ​ ​ ​ — % ​ — ​ $ 745,939 ​ 0.63 % 1.73 % ​ 700,000 ​ $ 538,627 ​ 2.35 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-term borrowings ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ SCBT Capital Trust I junior subordinated debt (1) ​ 6/15/2035 ​ 2.01 % 12,372 ​ ​ ​ ​ ​ ​ 3.68 % 12,372 ​ ​ ​ ​ ​ ​ SCBT Capital Trust II junior subordinated debt (1) ​ 6/15/2035 ​ 2.01 % 8,248 ​ ​ ​ ​ ​ ​ 3.68 % 8,248 ​ ​ ​ ​ ​ ​ SCBT Capital Trust III junior subordinated debt (1) ​ 7/18/2035 ​ 1.81 % ​ 20,619 ​ ​ ​ ​ ​ ​ 3.48 % ​ 20,619 ​ ​ ​ ​ ​ ​ SAVB Capital Trust I junior subordinated debt (1) ​ 10/7/2033 ​ 3.09 % 6,186 ​ ​ ​ ​ ​ ​ 4.84 % 6,186 ​ ​ ​ ​ ​ ​ SAVB Capital Trust II junior subordinated debt (1) ​ 12/15/2034 ​ 2.42 % 4,124 ​ ​ ​ ​ ​ ​ 4.09 % 4,124 ​ ​ ​ ​ ​ ​ TSB Statutory Trust I junior subordinated debt (1) ​ 3/14/2037 ​ 1.94 % 3,093 ​ ​ ​ ​ ​ ​ 3.61 % 3,093 ​ ​ ​ ​ ​ ​ Southeastern Bank Financial Statutory Trust I junior subordinated debt (1) ​ 12/15/2035 ​ 1.62 % 10,310 ​ ​ ​ ​ ​ ​ 3.29 % 10,310 ​ ​ ​ ​ ​ ​ Southeastern Bank Financial Statutory Trust II junior subordinated debt (1) ​ 6/15/2036 ​ 1.62 % 10,310 ​ ​ ​ ​ ​ ​ 3.29 % 10,310 ​ ​ ​ ​ ​ ​ CSBC Statutory Trust I junior subordinated debt (1) ​ 12/15/2035 ​ 1.79 % 15,464 ​ ​ ​ ​ ​ ​ 3.46 % 15,464 ​ ​ ​ ​ ​ ​ Community Capital Statutory Trust I junior subordinated debt (1) ​ 6/15/2036 ​ 1.77 % 10,310 ​ ​ ​ ​ ​ ​ 3.44 % 10,310 ​ ​ ​ ​ ​ ​ FCRV Statutory Trust I junior subordinated debt (1) ​ 12/15/2036 ​ 1.92 % 5,155 ​ ​ ​ ​ ​ ​ 3.59 % 5,155 ​ ​ ​ ​ ​ ​ Provident Community Bancshares Capital Trust I junior subordinated debt (1) ​ 3/1/2037 ​ 1.97 % 4,124 ​ ​ ​ ​ ​ ​ 3.84 % 4,124 ​ ​ ​ ​ ​ ​ Provident Community Bancshares Capital Trust II junior subordinated debt (1) ​ 10/1/2036 ​ 1.97 % 8,248 ​ ​ ​ ​ ​ ​ 3.65 % 8,248 ​ ​ ​ ​ ​ ​ CenterState Banks of Florida Statutory Trust I junior subordinated debt (1) ​ 9/22/2033 ​ 3.30 % ​ 10,310 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Valrico Capital Statutory Trust junior subordinated debt (1) ​ 9/8/2034 ​ 2.93 % ​ 2,577 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Federal Trust Statutory Trust I junior subordinated debt (1) ​ 9/17/2033 ​ 3.18 % ​ 5,155 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Gulfstream Bancshares Capital Trust II junior subordinated debt (1) ​ 3/6/2037 ​ 1.93 % ​ 3,093 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Homestead Statutory Trust I junior subordinated debt (1) ​ 10/1/2036 ​ 1.88 % ​ 10,495 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ BSA Financial Statutory Trust I junior subordinated debt (1) ​ 12/15/2035 ​ 1.77 % ​ 5,155 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ MRCB Statutory Trust II junior subordinated debt (1) ​ 9/15/2036 ​ 1.82 % ​ 3,093 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Fair Market Value Discount Trust Preferred Debt Acquired ​ ​ ​ ​ ​ ​ (14,116) ​ ​ ​ ​ ​ ​ ​ ​ ​ (2,730) ​ ​ ​ ​ ​ ​ Total Junior Subordinated Debt ​ ​ ​ 2.05 % ​ 144,325 ​ ​ 131,817 ​ 2.51 % 3.60 % ​ 115,833 ​ ​ 115,490 ​ 4.20 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Residential Warranty Corp. subordinated note (5) ​ 4/15/2021 ​ 5.00 % ​ 7,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Messiah College subordinated note (5) ​ 4/15/2021 ​ 5.00 % ​ 4,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ National Bank of Commerce subordinated debt (2) ​ 6/1/2026 ​ 6.00 % ​ 25,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Landmark Bancshares subordinated debt (3) ​ 6/30/2027 ​ 6.50 % ​ 13,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ CenterState Bank Corporation subordinated debt (4) ​ 6/1/2030 ​ 5.75 % ​ 200,000 ​ ​ ​ ​ ​ ​ — % ​ — ​ ​ ​ ​ ​ ​ Long-term subordinated debt costs ​ ​ ​ ​ ​ ​ (3,146) ​ ​ ​ ​ ​ ​ ​ ​ ​ — ​ ​ ​ ​ ​ ​ Total Subordinated Debt ​ ​ ​ 5.78 % ​ 245,854 ​ ​ 139,584 ​ 5.69 % — % ​ — ​ ​ — ​ — % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other Long Term Debt ​ Various ​ — % ​ — ​ ​ 92 ​ 0.50 % 0.50 % 103 ​ ​ 636 ​ 6.02 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total long-term borrowings ​ ​ ​ 4.40 % ​ 390,179 ​ ​ 271,493 ​ 3.60 % 3.60 % ​ 115,936 ​ ​ 116,126 ​ 3.60 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total borrowings ​ ​ ​ 4.40 % $ 390,179 ​ $ 1,017,432 ​ 1.58 % 2.00 % $ 815,936 ​ $ 654,753 ​ 2.57 % ​ (1) All of the junior subordinated debt above is adjustable rate based on three-month LIBOR plus a spread ranging from (2) The Notes bear interest at a fixed rate of per year, from, and including, May 19, 2016, to, but excluding, June 1, 2021. On June 1, 2021, the Notes convert to a floating rate equal to three-month LIBOR plus bps. The Notes may be redeemed by the Company after June 1, 2021. (3) The Notes bear interest at a fixed rate of per year, to, but excluding, June 30, 2022. On June 30, 2022, the Notes convert to a floating rate equal to three-month LIBOR plus bps. The Notes may be redeemed by the Company after June 30, 2022. (4) The per year, to, but excluding, June 1, 2025. On June 1, 2025, the Notes convert to a floating rate equal to SOFR plus bps. The Notes may be redeemed by the Company after June 1, 2025. The carrying balance of this debt is (5) These subordinated notes are not classified as Tier 2 Capital for regulatory capital purposes.
Summary of principal maturities of other borrowings	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Junior ​ ​ ​ ​ ​ Subordinated ​ FHLB ​ Subordinated ​ ​ (Dollars in thousands) Debt ​ Advances ​ Debt ​ Total Year Ended December 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 $ — ​ $ — ​ $ 11,000 ​ $ 11,000 ​ 2022 — ​ — ​ — ​ — ​ 2023 — ​ — ​ — ​ — ​ 2024 — ​ — ​ — ​ — ​ 2025 — ​ — ​ — ​ — ​ Thereafter 144,325 ​ — ​ 234,854 ​ 379,179 ​ ​ $ 144,325 ​ $ — ​ $ 245,854 ​ $ 390,179 ​

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Taxes
Schedule of provision for income taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Current: ​ ​ ​ ​ Federal ​ $ 16,245 ​ $ 40,375 ​ $ 25,275 ​ State ​ 13,296 ​ 4,965 ​ 6,783 ​ Total current tax expense ​ 29,541 ​ 45,340 ​ 32,058 ​ Deferred: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ (36,801) ​ (1,598) ​ 12,557 ​ State ​ (9,400) ​ 200 ​ 769 ​ Total deferred tax (benefit) expense ​ (46,201) ​ (1,398) ​ 13,326 ​ (Benefit) provision for income taxes ​ $ (16,660) ​ $ 43,942 ​ $ 45,384 ​
Analysis of difference between the provision for income taxes and taxes computed by applying the federal statutory income tax rate to income before provision for income taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Income taxes at federal statutory rate $ 21,834 $ 48,389 $ 47,094 ​ Increase (reduction) of taxes resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State income taxes, net of federal tax benefit ​ 3,077 ​ 4,080 ​ 5,916 ​ Non-deductible merger expenses ​ ​ 1,344 ​ ​ — ​ ​ — ​ Increase in cash surrender value of BOLI policies ​ ​ (2,389) ​ ​ (1,210) ​ ​ (1,261) ​ Tax-exempt interest ​ (2,257) ​ (1,877) ​ (2,037) ​ Income tax credits ​ (7,138) ​ (6,881) ​ (3,118) ​ Non-deductible FDIC premiums ​ ​ 1,364 ​ ​ 133 ​ ​ 191 ​ Non-deductible executive compensation ​ ​ 1,016 ​ ​ 315 ​ ​ 305 ​ Revaluation of net deferred tax asset due to tax law change ​ ​ — ​ ​ — ​ ​ (991) ​ Benefit of tax loss carryback under CARES Act ​ ​ (31,468) ​ ​ — ​ ​ — ​ Other, net ​ (2,043) ​ 993 ​ (715) ​ ​ ​ $ (16,660) ​ $ 43,942 ​ $ 45,384 ​
Schedule of components of the net deferred tax asset	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 Allowance for credit losses $ 119,602 $ 14,468 ​ Other-than-temporary impairment on securities ​ 268 ​ 250 ​ Share-based compensation ​ 2,807 ​ 4,975 ​ Pension plan and post-retirement benefits ​ 516 ​ 494 ​ Deferred compensation ​ 13,671 ​ 12,475 ​ Purchase accounting adjustments ​ 11,772 ​ 24,530 ​ Other real estate owned ​ 899 ​ 380 ​ Net operating loss and tax credit carryforwards ​ 26,229 ​ 10,347 ​ Deferred loan fees and costs ​ ​ 12,826 ​ ​ — ​ Nonaccrual Interest ​ ​ 3,141 ​ ​ — ​ Lease liability ​ ​ 28,179 ​ ​ 19,146 ​ Cash flow hedge ​ — ​ 3,034 ​ Other ​ 603 ​ 1,040 ​ Total deferred tax assets ​ 220,513 ​ 91,139 ​ Unrealized gains on investment securities available for sale ​ 13,026 ​ 2,373 ​ Depreciation ​ 18,326 ​ 6,585 ​ Intangible assets ​ 34,648 ​ 9,979 ​ Net deferred loan costs ​ — ​ 9,082 ​ Right of use assets ​ ​ 27,012 ​ ​ 19,465 ​ Prepaid expense ​ 1,950 ​ 474 ​ Tax deductible goodwill ​ 1,302 ​ 810 ​ Mortgage servicing rights ​ ​ 6,134 ​ ​ 6,688 ​ Other ​ 1,534 ​ 480 ​ Total deferred tax liabilities ​ 103,932 ​ 55,936 ​ Net deferred tax assets before valuation allowance ​ 116,581 ​ 35,203 ​ Less, valuation allowance ​ (5,635) ​ (3,887) ​ Net deferred tax assets ​ $ 110,946 ​ $ 31,316 ​

Other Expense (Tables)

Other Expense (Tables)	12 Months Ended
	Dec. 31, 2020
Other Expense
Summary of the components of other noninterest expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Business development and staff related $ 8,721 $ 8,837 $ 9,536 ​ Bankcard expense ​ ​ 2,224 ​ ​ 2,331 ​ ​ 1,783 ​ Other loan expense ​ ​ 5,105 ​ ​ 2,087 ​ ​ 2,028 ​ Director and shareholder expense ​ ​ 4,175 ​ ​ 1,859 ​ ​ 2,065 ​ Armored carrier and courier expense ​ ​ 2,449 ​ ​ 1,874 ​ ​ 2,102 ​ Property and sales tax ​ 3,936 ​ 2,131 ​ 1,760 ​ Low income housing tax credit partnership amortization ​ ​ 12,977 ​ ​ 6,141 ​ ​ 3,829 ​ Donation ​ ​ 2,121 ​ ​ 999 ​ ​ 960 ​ Other ​ 11,137 ​ 5,234 ​ 5,312 ​ ​ ​ $ 52,845 ​ $ 31,493 ​ $ 29,375 ​

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Common Share
Schedule of computation of basic and diluted earnings per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars and shares in thousands, except for per share amounts) ​ 2020 ​ 2019 ​ 2018 Basic earnings per common share: ​ ​ ​ ​ Net income ​ ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 Weighted-average basic common shares ​ ​ ​ 54,756 ​ ​ 34,561 ​ ​ 36,530 Basic earnings per common share ​ ​ $ 2.20 ​ $ 5.40 ​ $ 4.90 Basic earnings per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income ​ ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 Weighted-average basic common shares ​ ​ ​ 54,756 ​ ​ 34,561 ​ ​ 36,530 Effect of dilutive securities ​ ​ ​ 307 ​ ​ 236 ​ ​ 246 Weighted-average dilutive shares ​ ​ ​ 55,063 ​ ​ 34,797 ​ ​ 36,776 Basic earnings per common share ​ ​ $ 2.19 ​ $ 5.36 ​ $ 4.86
Schedule of anti-dilutive securities excluded from computation of diluted earnings per common share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Number of shares ​ ​ ​ ​ ​ 136,844 ​ ​ ​ 62,235 ​ ​ ​ ​ 62,235 Range of exercise prices ​ ​ $ 61.42 to $ 91.35 ​ $ 87.30 to $ 91.35 ​ $ 87.30 to $ 91.35 ​

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss)
Schedule of components of accumulated other comprehensive income (loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unrealized Gains ​ ​ ​ ​ ​ ​ ​ ​ ​ and Losses ​ Gains and ​ ​ ​ ​ ​ ​ ​ ​ on Securities ​ Losses on ​ ​ ​ ​ ​ Benefit ​ Available ​ Cash Flow ​ ​ ​ (Dollars in thousands) ​ Plans ​ for Sale ​ Hedges ​ Total Balance at December 31, 2017 ​ $ (5,998) ​ $ (4,278) ​ $ (151) ​ $ (10,427) Other comprehensive income (loss) before reclassifications ​ 382 ​ ​ (13,479) ​ ​ 33 ​ (13,064) Amounts reclassified from accumulated other comprehensive loss ​ 926 ​ ​ 510 ​ ​ 121 ​ 1,557 Net comprehensive income (loss) ​ 1,308 ​ (12,969) ​ 154 ​ (11,507) AOCI reclassification to retained earnings from the adoption of ASU 2018-02 ​ ​ (1,760) ​ ​ (1,147) ​ ​ (40) ​ (2,947) Balance at December 31, 2018 ​ (6,450) ​ ​ (18,394) ​ ​ (37) ​ (24,881) Other comprehensive income (loss) before reclassifications ​ 20 ​ ​ 28,245 ​ ​ (10,447) ​ 17,818 Amounts reclassified from accumulated other comprehensive income ​ 6,281 ​ ​ 2,071 ​ ​ (272) ​ 8,080 Net comprehensive income (loss) ​ 6,301 ​ 30,316 ​ (10,719) ​ 25,898 Balance at December 31, 2019 ​ (149) ​ 11,922 ​ (10,756) ​ 1,017 Other comprehensive income (loss) before reclassifications ​ (119) ​ 35,857 ​ (26,140) ​ 9,598 Amounts reclassified from accumulated other comprehensive income ​ 117 ​ (39) ​ 36,896 ​ 36,974 Net comprehensive income (loss) ​ (2) ​ 35,818 ​ 10,756 ​ 46,572 Balance at December 31, 2020 ​ $ (151) ​ $ 47,740 ​ $ — ​ $ 47,589
Schedule of reclassifications out of accumulated other comprehensive income (loss), net of tax	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount Reclassified from Accumulated ​ ​ ​ (Dollars in thousands) ​ ​ For the Years Ended December 31, ​ ​ ​ Accumulated Other Comprehensive Income (Loss) Component ​ 2020 2019 2018 ​ Income Statement (Gains) losses on cash flow hedges: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts ​ ​ $ 47,303 ​ $ (349) ​ $ 155 ​ Interest expense ​ ​ ​ ​ (10,407) ​ 77 ​ ​ (34) ​ Provision for income taxes ​ ​ ​ ​ 36,896 ​ (272) ​ ​ 121 ​ Net income (Gains) losses on sales of available-for-sale securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ (50) ​ $ 2,655 ​ $ 655 ​ ​ Securities gains (losses), net ​ ​ ​ ​ 11 ​ ​ (584) ​ ​ (145) ​ ​ Provision for income taxes ​ ​ ​ ​ (39) ​ ​ 2,071 ​ ​ 510 ​ ​ Net income Losses and amortization of defined benefit pension: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Actuarial losses ​ ​ $ 152 ​ $ 8,053 ​ $ 1,187 ​ Salaries and employee benefits ​ ​ ​ ​ (35) ​ (1,772) ​ ​ (261) ​ Provision for income taxes ​ ​ ​ ​ 117 ​ 6,281 ​ ​ 926 ​ Net income Total reclassifications for the period ​ ​ $ 36,974 ​ $ 8,080 ​ $ 1,557 ​ ​ ​

Retirement Plans (Tables)

Retirement Plans (Tables) - Non-contributory defined benefit pension plan	12 Months Ended
	Dec. 31, 2020
Retirement Plans
Schedule of the pension plan's funded status and amounts recognized in the company's accompanying consolidated financial statements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Change in benefit obligation: ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ — ​ $ 28,906 ​ $ 31,500 ​ Service cost ​ ​ — ​ ​ 121 ​ ​ 77 ​ Interest cost ​ — ​ 1,158 ​ 1,080 ​ Actuarial (gain) loss ​ — ​ 2,471 ​ (2,442) ​ Benefits paid ​ — ​ (538) ​ (1,188) ​ Expenses ​ ​ — ​ ​ (318) ​ ​ (121) ​ Plan termination settlements ​ ​ — ​ ​ (31,800) ​ ​ — ​ Benefit obligation at end of year ​ — ​ — ​ 28,906 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ — ​ 30,545 ​ 31,387 ​ Actual return on plan assets ​ — ​ 2,111 ​ 467 ​ Benefits paid ​ — ​ (538) ​ (1,188) ​ Expenses ​ ​ — ​ ​ (318) ​ ​ (121) ​ Plan termination settlements ​ ​ — ​ ​ (31,800) ​ ​ — ​ Fair value of plan assets at end of year ​ — ​ — ​ 30,545 ​ Funded (unfunded) status ​ $ — ​ $ — ​ $ 1,639 ​
Schedule of components of net periodic benefit cost and other amounts recognized in other comprehensive income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Interest cost $ — $ 1,157 $ 1,079 Service cost ​ ​ — ​ ​ 121 ​ ​ 78 Expected return on plan assets ​ — ​ (2,361) ​ (2,328) Recognized net actuarial loss ​ — ​ 483 ​ 775 Net periodic pension benefit ​ — ​ (600) ​ (396) Plan termination settlement ​ ​ — ​ ​ 10,126 ​ ​ — Net periodic pension cost with settlement ​ ​ — ​ ​ 9,526 ​ ​ — Net (gain) loss ​ — ​ 2,722 ​ (581) Amortization of net gain ​ — ​ (483) ​ (775) Plan termination settlement adjustment ​ ​ — ​ ​ (10,126) ​ ​ — Total amount recognized in other comprehensive income ​ — ​ (7,887) ​ (1,356) Total recognized in net periodic benefit cost and other comprehensive income ​ $ — ​ $ 1,639 ​ $ (1,752)
Schedule of weighted average assumptions used to determine benefit obligations and net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended ​ ​ December 31, ​ ​ 2020 ​ 2019 ​ 2018 Discount rate — % 4.10 % 3.50 % Expected long-term return on plan assets — % 7.75 % 7.75 %
Schedule of expenses incurred and charged against operations with regard to all of the company's retirement plans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Pension $ — $ — $ (309) ​ Pension plan termination expense ​ ​ — ​ ​ 9,526 ​ ​ — ​ Employee savings plan/ 401(k) ​ 10,962 ​ 6,659 ​ 7,948 ​ Supplemental executive retirement plan ​ 2,862 ​ 2,343 ​ 368 ​ Post-retirement benefits ​ 43 ​ 144 ​ 254 ​ ​ ​ $ 13,867 ​ $ 18,672 ​ $ 8,261 ​

Post-Retirement Benefits (Table

Post-Retirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2020
SCBT Post-retirement Benefit Plan
Post-Retirement Benefits
Schedule of the plan's funded status and amounts recognized in the Company's accompanying consolidated financial statements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Change in benefit obligation: ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ 254 ​ $ 309 ​ $ 337 ​ Interest cost ​ 6 ​ 11 ​ 11 ​ Actuarial loss ​ (19) ​ (33) ​ 2 ​ Benefits paid ​ (32) ​ (33) ​ (41) ​ Benefit obligation at end of year ​ 209 ​ 254 ​ 309 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ — ​ — ​ — ​ Employer contribution ​ 32 ​ 33 ​ 41 ​ Benefits paid ​ (32) ​ (33) ​ (41) ​ Fair value of plan assets at end of year ​ — ​ — ​ — ​ Funded status ​ $ (209) ​ $ (254) ​ $ (309) ​
Schedule of weighted average assumptions used to determine benefit obligations and net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2020 ​ 2019 ​ 2018 Weighted-average assumptions used to determine benefit obligation at December 31: ​ Discount rate 1.60 % 2.70 % 3.80 % Weighted-average assumptions used to determine net periodic benefit cost for years ended December 31: ​ ​ ​ ​ ​ ​ ​ Discount rate 2.70 % 3.80 % 3.20 % Assumed health care cost trend rates at December 31: ​ ​ ​ ​ ​ ​ ​ Health care cost trend rate assumed for next year 5.00 % 5.00 % 5.00 %
Schedule of components of net periodic benefit cost and other amounts recognized in other comprehensive income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Interest cost $ 6 $ 11 $ 10 ​ Recognized net actuarial loss ​ 2 ​ 6 ​ 6 ​ Net periodic benefit cost ​ 8 ​ 17 ​ 16 ​ Net (gain) loss ​ (19) ​ (33) ​ 2 ​ Amortization of gain ​ (2) ​ (6) ​ (6) ​ Total amount recognized in other comprehensive income ​ (21) ​ (39) ​ (4) ​ Total recognized in net periodic benefit cost and other comprehensive income ​ $ (13) ​ $ (22) ​ $ 12 ​
Schedule of effects of one-percentage-point change in assumed health care cost trend rates	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One-Percentage Point (Dollars in thousands) ​ Increase ​ Decrease Effect on total of interest cost $ 1 $ (1) ​ Effect on postretirement benefit obligation ​ 10 ​ (10) ​
Schedule of estimated future benefit payments (including expected future service as appropriate)	​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2021 ​ $ 27 ​ 2022 ​ 25 ​ 2023 ​ 24 ​ 2024 ​ 22 ​ 2025 ​ 20 ​ 2026-2030 ​ 71 ​ ​ ​ $ 189 ​
FFCH Post-retirement Benefit Plan
Post-Retirement Benefits
Schedule of the plan's funded status and amounts recognized in the Company's accompanying consolidated financial statements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2020 2019 2018 ​ Change in benefit obligation: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ 2,109 ​ $ 2,281 ​ $ 2,392 ​ Interest cost ​ ​ 54 ​ 82 ​ 73 ​ Actuarial loss ​ ​ 180 ​ 7 ​ 89 ​ Benefits paid ​ ​ (285) ​ (273) ​ (286) ​ Less: Federal subsidy on benefits paid ​ ​ 12 ​ 12 ​ 13 ​ Benefit obligation at end of year ​ ​ 2,070 ​ 2,109 ​ 2,281 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ ​ — ​ — ​ — ​ Employer contribution ​ ​ 273 ​ 261 ​ 286 ​ Participants’ contributions ​ ​ 12 ​ 12 ​ — ​ Benefits paid ​ ​ (285) ​ (273) ​ (286) ​ Fair value of plan assets at end of year ​ ​ — ​ — ​ — ​ Funded status ​ $ (2,070) ​ $ (2,109) ​ $ (2,281) ​
Schedule of weighted average assumptions used to determine benefit obligations and net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2020 2019 ​ 2018 ​ Weighted-average assumptions used to determine benefit obligation at December 31: ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 1.60 % 2.70 % 3.80 % Weighted-average assumptions used to determine net periodic benefit cost for years ended December 31: ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 2.70 % 3.80 % 3.20 % Assumed health care cost trend rates at December 31: ​ ​ ​ ​ ​ ​ ​ Health care cost trend rate assumed for next year ​ 5.00 % 5.00 % 5.00 %
Schedule of components of net periodic benefit cost and other amounts recognized in other comprehensive income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) 2020 2019 2018 Interest cost ​ $ 54 ​ $ 82 ​ $ 73 ​ Recognized net actuarial loss ​ ​ 151 ​ 160 ​ 154 ​ Net periodic benefit cost ​ ​ 205 ​ 242 ​ 227 ​ Net loss ​ ​ 180 ​ 7 ​ 89 ​ Amortization of loss ​ ​ (151) ​ (160) ​ (154) ​ Total amount recognized in other comprehensive income ​ ​ 29 ​ (153) ​ (65) ​ Total recognized in net periodic benefit cost and other comprehensive income ​ $ 234 ​ $ 89 ​ $ 162 ​
Schedule of effects of one-percentage-point change in assumed health care cost trend rates	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One-Percentage Point (Dollars in thousands) ​ Increase ​ Decrease Effect on aggregate service and interest cost $ 4 $ (3) ​ Effect on postretirement benefit obligation ​ ​ 125 ​ ​ (114) ​
Schedule of estimated future benefit payments (including expected future service as appropriate)	​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2021 ​ $ 243 ​ 2022 ​ 229 ​ 2023 ​ 213 ​ 2024 ​ 198 ​ 2025 ​ 181 ​ 2026-2030 ​ 671 ​ ​ ​ $ 1,735 ​

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-Based Compensation
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2020 ​ 2019 ​ 2018 ​ ​ ​ ​ ​ Weighted ​ ​ ​ Weighted ​ ​ ​ Weighted ​ ​ ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ Average ​ ​ ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ ​ Exercise ​ ​ Shares ​ Price ​ Shares ​ Price ​ Shares ​ Price Outstanding at January 1, 2020 ​ 176,888 $ 67.14 213,866 $ 61.28 218,689 $ 52.75 ​ Granted ​ — ​ — ​ — ​ — ​ 34,407 ​ 91.05 ​ Assumed stock options and warrants from CSFL merger ​ ​ 136,831 ​ ​ 37.85 ​ — ​ ​ — ​ — ​ ​ — ​ Exercised ​ (52,331) ​ 32.12 ​ (36,978) ​ 33.26 ​ (33,424) ​ 30.88 ​ Forfeited ​ (4,963) ​ 48.89 ​ — ​ — ​ (5,806) ​ 91.35 ​ Outstanding at December 31, 2020 ​ 256,425 ​ 59.01 ​ 176,888 ​ 67.14 ​ 213,866 ​ 61.28 ​ Exercisable at December 31, 2020 ​ 256,425 ​ 59.01 ​ 131,216 ​ 60.12 ​ 140,115 ​ 49.41 ​ Weighted-average fair value of options granted during the year ​ ​ ​ ​ $ — ​ ​ ​ $ — ​ ​ ​ $ 28.01 ​
Schedule of information pertaining to options outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ ​ ​ ​ ​ Remaining ​ Weighted ​ ​ ​ Weighted ​ Remaining ​ Range of ​ Number ​ Contractual ​ Average ​ Number ​ Average ​ Contractual ​ Exercise Prices ​ Outstanding ​ Life ​ Exercise Price ​ Outstanding ​ Exercise Price ​ Life ​ $ 19.16 - $ 40.00 45,002 3.1 years ​ $ 31.11 45,002 ​ $ 31.11 3.1 years $ 40.01 - $ 55.00 74,579 7.7 years ​ $ 44.46 74,579 ​ $ 44.46 ​ 7.7 years $ 55.01 - $ 70.00 74,609 4.1 years ​ $ 63.61 74,609 ​ $ 63.61 ​ 4.1 years $ 70.01 - $ 85.00 ​ — ​ — years ​ $ — ​ — ​ $ — ​ — years $ 85.01 - $ 91.35 62,235 6.6 years ​ $ 91.12 ​ 62,235 ​ $ 91.12 ​ 6.6 years ​ ​ ​ ​ ​ 256,425 4.5 years ​ $ 59.01 256,425 ​ $ 59.01 4.5 years
Schedule of weighted-average assumptions used in valuing options	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2020 ​ 2019 2018 Dividend yield ​ — % ​ ​ — % 1.46 % Expected life — years ​ ​ — years 8.5 years Expected volatility — % ​ — % 28.0 % Risk-free interest rate — % ​ — % 2.54 %
Summary of nonvested restricted stock	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date Restricted Stock ​ Shares ​ Fair Value Nonvested at January 1, 2020 69,450 ​ $ 58.96 ​ Assumed restricted stock shares from CSFL merger ​ 9,755 ​ ​ 60.27 ​ Granted 9,145 ​ 55.96 ​ Vested (77,029) ​ 58.67 ​ Forfeited (317) ​ 65.86 ​ Nonvested at December 31, 2020 11,004 ​ $ 59.42 ​
Vesting schedule of shares	​ ​ ​ ​ ​ ​ Shares 2021 7,935 ​ 2022 751 ​ 2023 751 ​ 2024 1,567 ​ 2025 — ​ Thereafter — ​ ​ 11,004 ​
Summary of nonvested RSUs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date Restricted Stock Units ​ Shares ​ Fair Value Nonvested at January 1, 2020 324,601 ​ $ 76.44 ​ Assumed restricted stock units from CSFL merger ​ 388,381 ​ ​ 60.27 ​ Granted 382,205 ​ 61.27 ​ Vested ​ (275,661) ​ ​ 75.63 ​ Forfeited ​ (68,705) ​ ​ 74.09 ​ Nonvested at December 31, 2020 750,821 ​ $ 60.88 ​

Lease Commitments (Tables)

Lease Commitments (Tables)	12 Months Ended
	Dec. 31, 2020
Leases
Schedule of information pertaining to operating leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Year Ended December 31, ​ 2020 2019 Lease Cost Components: ​ ​ ​ ​ ​ ​ ​ ​ Amortization of ROU assets - finance leases ​ $ 289 ​ $ — ​ ​ Interest on lease liabilities - finance leases ​ ​ 44 ​ ​ — ​ ​ Operating lease cost (cost resulting from lease payments) ​ ​ 14,266 ​ ​ 8,804 ​ ​ Short-term lease cost ​ ​ 404 ​ ​ 494 ​ ​ Variable lease cost (cost excluded from lease payments) ​ 1,081 ​ 430 ​ ​ Total lease cost ​ $ 16,084 ​ $ 9,728 ​ ​ Supplemental Cash Flow and Other Information Related to Leases: ​ ​ ​ ​ ​ ​ ​ ​ Finance lease - operating cash flows ​ $ 42 ​ $ — ​ ​ Finance lease - financing cash flows ​ ​ 255 ​ ​ — ​ ​ Operating lease - operating cash flows (fixed payments) ​ 12,876 ​ 7,725 ​ ​ Operating lease - operating cash flows (net change asset/liability) ​ ​ (9,123) ​ ​ 1,457 ​ ​ New ROU assets - operating leases ​ ​ 43,583 ​ ​ 10,239 ​ ​ New ROU assets - finance leases ​ ​ 5,374 ​ ​ ​ ​ ​ Weighted - average remaining lease term (years) - finance leases ​ ​ 7.40 ​ ​ ​ ​ ​ Weighted - average remaining lease term (years) - operating leases ​ 11.51 ​ 14.14 ​ ​ Weighted - average discount rate - finance leases ​ ​ 1.7% ​ ​ ​ ​ ​ Weighted - average discount rate - operating leases ​ 3.3% ​ 3.9% ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease payments due: ​ ​ ​ ​ ​ ​ ​ ​ 2021 ​ $ 15,753 ​ ​ ​ ​ 2022 ​ 14,508 ​ ​ ​ ​ 2023 ​ 13,482 ​ ​ ​ ​ 2024 ​ 12,212 ​ ​ ​ ​ 2025 ​ ​ 10,747 ​ ​ ​ ​ ​ Thereafter ​ 78,711 ​ ​ ​ ​ ​ Total undiscounted cash flows ​ 145,413 ​ ​ ​ ​ ​ Discount on cash flows ​ ​ (27,092) ​ ​ ​ ​ ​ Total operating lease liabilities ​ $ 118,321 ​ ​ ​ ​ ​

Financial Instruments with Of_2

Financial Instruments with Off-Balance Sheet Risk (Tables)	12 Months Ended
	Dec. 31, 2020
Financial Instruments with Off-Balance Sheet Risk
Schedule of financial instruments of the subsidiary, whose contract amounts represent credit risk	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ (Dollars in thousands) ​ 2020 ​ 2019 ​ Commitments to extend credit ​ $ 5,929,845 ​ $ 2,902,000 ​ Standby letters of credit and financial guarantees ​ 76,507 ​ 32,869 ​ ​ ​ $ 6,006,352 ​ $ 2,934,869 ​

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value
Schedule of recorded amount of assets and liabilities measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Prices ​ ​ ​ ​ ​ ​ ​ ​ ​ In Active ​ Significant ​ ​ ​ ​ ​ ​ ​ ​ Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs (Dollars in thousands) ​ Fair Value ​ (Level 1) ​ (Level 2) ​ (Level 3) December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 813,899 ​ $ — ​ $ 813,899 ​ $ — Loans held for sale ​ 290,467 ​ — ​ 290,467 ​ — Trading securities ​ 10,674 ​ — ​ 10,674 ​ — Securities available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ ​ 29,256 ​ ​ — ​ ​ 29,256 ​ ​ — State and municipal obligations ​ 520,039 ​ — ​ 520,039 ​ — Mortgage-backed securities ​ 2,767,675 ​ — ​ 2,767,675 ​ — Corporate securities ​ ​ 13,702 ​ ​ — ​ ​ 13,702 ​ ​ — Total securities available-for-sale ​ 3,330,672 ​ — ​ 3,330,672 ​ — Mortgage servicing rights ​ 43,820 ​ — ​ — ​ 43,820 ​ ​ $ 4,489,532 ​ $ — ​ $ 4,445,712 ​ $ 43,820 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 804,832 ​ $ — ​ $ 804,832 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 16,252 ​ $ — ​ $ 16,252 ​ $ — Loans held for sale ​ 59,363 ​ — ​ 59,363 ​ — Securities available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Government-sponsored entities debt ​ ​ 25,941 ​ ​ — ​ ​ 25,941 ​ ​ — State and municipal obligations ​ 208,415 ​ — ​ 208,415 ​ — Mortgage-backed securities ​ 1,721,691 ​ — ​ 1,721,691 ​ — Total securities available-for-sale ​ 1,956,047 ​ — ​ 1,956,047 ​ — Mortgage servicing rights ​ 30,525 ​ — ​ — ​ 30,525 ​ ​ $ 2,062,187 ​ $ — ​ $ 2,031,662 ​ $ 30,525 Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative financial instruments ​ $ 31,273 ​ $ — ​ $ 31,273 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of reconciliation of the beginning and ending balances of Level 3 assets and liabilities recorded at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Assets Liabilities Fair value, January 1, 2020 ​ $ 30,525 ​ $ — ​ Servicing assets that resulted from transfers of financial assets ​ 28,456 ​ — ​ Changes in fair value due to valuation inputs or assumptions ​ (6,991) ​ — ​ Changes in fair value due to decay ​ (8,170) ​ — ​ Fair value, December 31, 2020 ​ $ 43,820 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value, January 1, 2019 ​ $ 34,727 ​ $ — ​ Servicing assets that resulted from transfers of financial assets ​ 7,363 ​ — ​ Changes in fair value due to valuation inputs or assumptions ​ ​ (6,976) ​ ​ — ​ Changes in fair value due to decay ​ (4,589) ​ — ​ Fair value, December 31, 2019 ​ $ 30,525 ​ $ — ​
Schedule of amounts of assets and liabilities measured at fair value on a nonrecurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted Prices ​ ​ ​ ​ ​ ​ ​ ​ ​ In Active ​ Significant ​ ​ ​ ​ ​ ​ ​ ​ Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs (Dollars in thousands) ​ Fair Value ​ (Level 1) ​ (Level 2) ​ (Level 3) December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ OREO ​ $ 11,914 ​ $ — ​ $ — ​ $ 11,914 ​ Bank property held for sale ​ ​ 36,006 ​ ​ — ​ — ​ ​ 36,006 ​ Impaired loans ​ 17,609 ​ — ​ — ​ 17,609 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ OREO ​ $ 6,539 ​ $ — ​ $ — ​ $ 6,539 ​ Bank property held for sale ​ ​ 5,425 ​ ​ — ​ — ​ ​ 5,425 ​ Non-acquired impaired loans ​ 15,444 ​ — ​ — ​ 15,444 ​
Quantitative Information about Level 3 Fair Value Measurements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Average ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ Valuation Technique Unobservable Input 2020 2019 Nonrecurring measurements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Impaired loans Discounted appraisals and discounted cash flows Collateral discounts ​ 5 % ​ 2 % OREO and premises held for sale Discounted appraisals Collateral discounts and estimated costs to sell ​ 14 % ​ 31 %
Schedule of estimated fair value, and related carrying amount, of the Company's financial instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Fair ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ Amount ​ Value ​ Level 1 ​ Level 2 ​ Level 3 December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financial assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 4,609,255 ​ $ 4,609,255 ​ $ 4,609,255 ​ $ — ​ $ — ​ Trading securities ​ ​ 10,674 ​ ​ 10,674 ​ ​ — ​ ​ 10,674 ​ ​ — ​ Investment securities ​ 4,446,657 ​ 4,448,300 ​ 160,443 ​ 4,287,857 ​ — ​ Loans held for sale ​ ​ 290,467 ​ ​ 290,467 ​ ​ — ​ ​ 290,467 ​ ​ — ​ Loans, net of allowance for loan losses ​ 24,206,825 ​ 24,757,859 ​ — ​ — ​ 24,757,859 ​ Accrued interest receivable ​ 107,601 ​ 107,601 ​ — ​ 12,952 ​ 94,649 ​ Mortgage servicing rights ​ 43,820 ​ 43,820 ​ — ​ — ​ 43,820 ​ Interest rate swap - non-designated hedge ​ 802,763 ​ 802,763 ​ — ​ 802,763 ​ — ​ Other derivative financial instruments (mortgage banking related) ​ 11,136 ​ 11,136 ​ — ​ 11,136 ​ — ​ Financial liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 30,693,882 ​ 30,719,416 ​ — ​ 30,719,416 ​ — ​ Federal funds purchased and securities sold under agreements to repurchase ​ 779,666 ​ 779,666 ​ — ​ 779,666 ​ — ​ Other borrowings ​ 390,179 ​ 386,126 ​ — ​ 386,126 ​ — ​ Accrued interest payable ​ 7,103 ​ 7,103 ​ — ​ 7,103 ​ — ​ Interest rate swap - non-designated hedge ​ 804,832 ​ 804,832 ​ — ​ 804,832 ​ — ​ Off balance sheet financial instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commitments to extend credit ​ — ​ 136,726 ​ — ​ 136,726 ​ — ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financial assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 688,704 ​ $ 688,704 ​ $ 688,704 ​ $ — ​ $ — ​ Investment securities ​ 2,005,171 ​ 2,005,171 ​ 49,124 ​ 1,956,047 ​ — ​ Loans held for sale ​ ​ 59,363 ​ ​ 59,363 ​ ​ — ​ ​ 59,363 ​ ​ — ​ Loans, net of allowance for loan losses ​ 11,313,113 ​ 11,452,003 ​ — ​ — ​ 11,452,003 ​ Accrued interest receivable ​ 36,774 ​ 36,774 ​ — ​ 8,500 ​ 28,274 ​ Mortgage servicing rights ​ 30,525 ​ 30,525 ​ — ​ — ​ 30,525 ​ Interest rate swap - non-designated hedge ​ 15,350 ​ 15,350 ​ — ​ 15,350 ​ — ​ Other derivative financial instruments (mortgage banking related) ​ 902 ​ 902 ​ — ​ 902 ​ — ​ Financial liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 12,177,096 ​ 11,406,477 ​ — ​ 11,406,477 ​ — ​ Federal funds purchased and securities sold under agreements to repurchase ​ 298,741 ​ 298,741 ​ — ​ 298,741 ​ — ​ Other borrowings ​ 815,936 ​ 818,210 ​ — ​ 818,210 ​ — ​ Accrued interest payable ​ 4,916 ​ 4,916 ​ — ​ 4,916 ​ — ​ Interest rate swap - non-designated hedge ​ 16,693 ​ 16,693 ​ — ​ 16,693 ​ — ​ Interest rate swap - cash flow hedge ​ 13,791 ​ 13,791 ​ — ​ 13,791 ​ — ​ Other derivative financial instruments (mortgage banking related) ​ ​ 789 ​ ​ 789 ​ — ​ 789 ​ — ​ Off balance sheet financial instruments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commitments to extend credit ​ ​ — ​ 36,031 ​ — ​ 36,031 ​ — ​

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2020
Regulatory Matters
Schedule of actual and required capital ratios	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Required to be ​ ​ ​ ​ ​ ​ ​ Minimum Capital Considered Well ​ ​ Actual ​ Required - Basel III ​ Capitalized ​ (Dollars in thousands) Amount Ratio Capital Amount Ratio Capital Amount Ratio December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Common equity Tier 1 to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ $ 3,010,174 11.77 % $ 1,789,984 ​ 7.00 % $ 1,662,128 6.50 % South State Bank (the Bank) ​ 3,157,098 12.39 % 1,784,120 ​ 7.00 % 1,656,683 6.50 % Tier 1 capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 3,010,174 11.77 % 2,173,552 ​ 8.50 % 2,045,696 8.00 % South State Bank (the Bank) ​ 3,157,098 12.39 % 2,166,432 ​ 8.50 % 2,038,994 8.00 % Total capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 3,642,039 14.24 % 2,684,976 ​ 10.50 % 2,557,120 10.00 % South State Bank (the Bank) ​ 3,397,463 13.33 % 2,676,180 ​ 10.50 % 2,548,743 10.00 % Tier 1 capital to average assets (leverage ratio): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 3,010,174 8.27 % 1,455,135 ​ 4.00 % 1,818,919 5.00 % South State Bank (the Bank) ​ 3,157,098 8.71 % 1,450,600 ​ 4.00 % 1,813,250 5.00 % December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Common equity Tier 1 to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ $ 1,326,725 11.30 % $ 822,225 ​ 7.00 % $ 763,495 6.50 % South State Bank (the Bank) ​ 1,417,616 12.07 % 822,218 ​ 7.00 % 763,488 6.50 % Tier 1 capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 1,438,995 12.25 % 998,416 ​ 8.50 % 939,686 8.00 % South State Bank (the Bank) ​ 1,417,616 12.07 % 998,407 ​ 8.50 % 939,677 8.00 % Total capital to risk-weighted assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 1,501,321 12.78 % 1,233,338 ​ 10.50 % 1,174,607 10.00 % South State Bank (the Bank) ​ 1,479,942 12.60 % 1,233,327 ​ 10.50 % 1,174,597 10.00 % Tier 1 capital to average assets (leverage ratio): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consolidated ​ 1,438,995 9.73 % 591,731 ​ 4.00 % 739,664 5.00 % South State Bank (the Bank) ​ 1,417,616 9.59 % 591,592 ​ 4.00 % 739,490 5.00 %

Condensed Financial Statement_2

Condensed Financial Statements of Parent Company (Tables)	12 Months Ended
	Dec. 31, 2020
Condensed Financial Statements of Parent Company
Schedule of condensed balance sheet	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) ​ 2020 ​ 2019 ASSETS ​ ​ ​ Cash ​ $ 131,522 ​ $ 21,688 ​ Investment in subsidiaries ​ 4,802,993 ​ 2,467,466 ​ Other assets ​ 108,086 ​ 204 ​ Total assets ​ $ 5,042,601 ​ $ 2,482,982 ​ LIABILITIES AND SHAREHOLDERS’ EQUITY ​ ​ ​ ​ ​ ​ ​ Corporate and subordinated debentures ​ $ 390,179 ​ $ 115,833 ​ Other liabilities ​ ​ 4,542 ​ ​ 512 ​ Shareholders’ equity ​ 4,647,880 ​ 2,373,013 ​ Total liabilities and shareholders’ equity ​ $ 5,042,601 ​ $ 2,482,982 ​
Schedule of condensed statements of income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Income: ​ ​ ​ ​ Dividends from subsidiary ​ $ 90,404 ​ $ 214,852 ​ $ 117,298 ​ Operating income ​ 52 ​ 5,386 ​ 67 ​ Total income ​ 90,456 ​ 220,238 ​ 117,365 ​ Operating expenses ​ 45,574 ​ 15,409 ​ 15,302 ​ Income before income tax benefit and equity in undistributed earnings of subsidiaries ​ 44,882 ​ 204,829 ​ 102,063 ​ Applicable income tax benefit ​ 8,960 ​ 1,883 ​ 3,055 ​ Equity in undistributed earnings of subsidiary (excess distribution) ​ 66,790 ​ (20,229) ​ 73,753 ​ Net income available to common shareholders ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 ​
Schedule of condensed statements of cash flows	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Cash flows from operating activities: ​ ​ ​ ​ Net income ​ $ 120,632 ​ $ 186,483 ​ $ 178,871 ​ Adjustments to reconcile net income to net cash provided by operating activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ 1,528 ​ 666 ​ 666 ​ Share-based compensation ​ 23,316 ​ 8,839 ​ 8,783 ​ Gain on sale of securities available-for-sale ​ — ​ (5,366) ​ — ​ Decrease (increase) in other assets ​ (11,710) ​ (159) ​ 1,465 ​ Decrease in other liabilities ​ (12,323) ​ (959) ​ (2,048) ​ Undistributed earnings of subsidiary ​ (66,790) ​ 20,229 ​ (73,753) ​ Net cash provided by operating activities ​ 54,653 ​ 209,733 ​ 113,984 ​ Cash flows from investing activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Proceeds from sales and calls of other investment securities ​ ​ — ​ ​ 5,366 ​ ​ — ​ Repayment of investments in and advances to subsidiary ​ ​ 163,000 ​ ​ — ​ ​ — ​ Net cash inflow from acquisitions ​ 19,650 ​ — ​ — ​ Net cash provided by investing activities ​ 182,650 ​ 5,366 ​ — ​ Cash flows from financing activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Common stock issuance ​ 1,537 ​ 1,394 ​ 1,331 ​ Common stock repurchased ​ (32,431) ​ (159,431) ​ (70,577) ​ Dividends paid on common stock ​ (98,256) ​ (57,696) ​ (50,557) ​ Stock options exercised ​ 1,681 ​ 1,230 ​ 1,032 ​ Net cash used in financing activities ​ (127,469) ​ (214,503) ​ (118,771) ​ Net increase (decrease) in cash and cash equivalents ​ 109,834 ​ 596 ​ (4,787) ​ Cash and cash equivalents at beginning of period ​ 21,688 ​ 21,092 ​ 25,879 ​ Cash and cash equivalents at end of period ​ $ 131,522 ​ $ 21,688 ​ $ 21,092 ​

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Financial Instruments
Derivative financial instruments summary	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ December 31, 2019 ​ ​ Balance Sheet ​ Notional ​ Estimated Fair Value ​ Notional ​ Estimated Fair Value (Dollars in thousands) Location Amount Gain Loss Amount Gain Loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash flow hedges of interest rate risk on FHLB Advances: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pay fixed rate swap with counterparty ​ Other Liabilities ​ $ — ​ $ — ​ $ — ​ $ 700,000 ​ $ — ​ $ 13,791 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value hedge of interest rate risk: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pay fixed rate swap with counterparty ​ Other Assets and Other Liabilities ​ $ 16,439 ​ $ — ​ $ 2,086 ​ $ 2,754 ​ $ — ​ $ 199 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Not designated hedges of interest rate risk: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Customer related interest rate contracts: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Matched interest rate swaps with borrowers ​ Other Assets and Other Liabilities ​ $ 9,324,359 ​ $ 802,717 ​ $ 46 ​ $ 564,068 ​ $ 15,277 ​ $ 1,019 Matched interest rate swaps with counterparty ​ Other Assets and Other Liabilities ​ $ 9,324,359 ​ $ 46 ​ $ 802,700 ​ $ 564,068 ​ $ 73 ​ $ 15,475 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Not designated hedges of interest rate risk - mortgage banking activities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contracts used to hedge mortgage servicing rights ​ Other Assets and Other Liabilities ​ $ 149,000 ​ $ 119 ​ $ — ​ $ 133,000 ​ $ — ​ $ 789 Contracts used to hedge mortgage pipeline ​ Other Assets ​ $ 528,500 ​ $ 11,017 ​ $ — ​ $ 87,773 ​ $ 902 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total derivatives ​ ​ ​ $ 19,342,657 ​ $ 813,899 ​ $ 804,832 ​ $ 2,051,663 ​ $ 16,252 ​ $ 31,273
Schedule of notional value of forward sale commitments and the fair value of those obligations along with the fair value of the mortgage pipeline	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2020 2019 Mortgage loan pipeline ​ ​ $ 510,730 ​ $ 80,785 Expected closures ​ ​ 411,273 ​ 60,588 Fair value of mortgage loan pipeline commitments ​ ​ 15,328 ​ 1,160 Forward sales commitments ​ ​ 528,500 ​ 87,773 Fair value of forward commitments ​ ​ (4,311) ​ (258)

Loan Servicing, Mortgage Orig_2

Loan Servicing, Mortgage Origination, and Loans Held for Sale (Tables)	12 Months Ended
	Dec. 31, 2020
Loan Servicing, Mortgage Origination, and Loans Held for Sale
Summary of changes in the fair value of MSRs and its offsetting hedge	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, (Dollars in thousands) ​ 2020 ​ 2019 ​ 2018 Increase (decrease) in fair value of MSRs ​ ​ $ (7,421) ​ $ (6,976) ​ $ 1,861 ​ Decay of MSRs ​ ​ (8,793) ​ (4,589) ​ (4,215) ​ Gain related to derivatives ​ ​ 10,177 ​ 3,967 ​ (953) ​ Net effect on statements of income ​ ​ $ (6,037) ​ $ (7,598) ​ $ (3,307) ​
Schedule of characteristics and sensitivity analysis of the MSR	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2020 2019 Composition of residential loans serviced for others ​ ​ ​ ​ ​ ​ ​ Fixed-rate mortgage loans ​ ​ 99.9 % ​ 99.8 % Adjustable-rate mortgage loans ​ ​ 0.1 % ​ 0.2 % Total ​ ​ 100.0 % ​ 100.0 % Weighted average life ​ ​ 6.10 years ​ 6.55 years Constant Prepayment rate (CPR) ​ ​ 12.3 % ​ 10.3 % Weighted average discount rate ​ ​ 9.0 % ​ 9.4 % Effect on fair value due to change in interest rates ​ ​ ​ ​ ​ ​ ​ 25 basis point increase ​ $ 2,744 ​ $ 2,477 ​ 50 basis point increase ​ ​ 5,520 ​ 4,452 ​ 25 basis point decrease ​ ​ (2,497) ​ (2,938) ​ 50 basis point decrease ​ ​ (4,114) ​ (6,228) ​

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Operations, Segments (Details)	12 Months Ended
	Dec. 31, 2020USD ($)itemsubsidiarysegment
Nature of Operations
Number of unconsolidated subsidiaries | subsidiary	20
Segments
Number of Operating Segments | segment	1
Investment in unconsolidated subsidiaries
Nature of Operations
Trust preferred securities to be issued | $	$ 153,500,000
South Carolina
Nature of Operations
Number of counties	28
NORTH CAROLINA
Nature of Operations
Number of counties | $	9
VIRGINIA
Nature of Operations
Number of counties	4
ALABAMA
Nature of Operations
Number of counties	5
GEORGIA
Nature of Operations
Number of counties	25
FLORIDA
Nature of Operations
Number of counties | $	32

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Concentrations of Credit Risk (Details) - Concentrations of Credit Risk $ in Millions	Dec. 31, 2020USD ($)item
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold (as a percent)	25.00%
Concentration risk threshold, total risk-based capital threshold	$ 841.1
Number of credit concentrations for non-acquired credit impaired loans | item	5
Lessors of residential and buildings
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold	$ 1,100
Lessors of nonresidential buildings
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold	3,700
Loans on hotels and motels
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold	969.9
Other holding companies
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold	3,100
Loans on owner occupied office buildings
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold	$ 3,600

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Held-to-maturity Securities	$ 955,542
Accrued interest receivable for investment securities	13,100
Threshold Net Book Balance, Individually Evaluated Loans	1,000
Interest Receivable	93,900
Liability Recorded for Expected Credit Losses on Unfunded Commitments		$ 6,400
Other Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest Receivable	93,900
Other Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liability Recorded for Expected Credit Losses on Unfunded Commitments	$ 43,400

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Summary of Significant Accounting Policies
Existence of option to extend	true
Renewal term	25 years
Right to use asset	$ 113,400	$ 87,400
Lease Liability	$ 118,321	$ 88,800
Minimum
Summary of Significant Accounting Policies
Lease terms	12 months
Maximum
Summary of Significant Accounting Policies
Lease terms	24 years
Adjustment for ASU | ASU 2016- 02
Summary of Significant Accounting Policies
Right to use asset			$ 82,200
Lease Liability			82,200
Adjustments | ASU 2016- 02
Summary of Significant Accounting Policies
Right to use asset			82,200
Lease Liability			$ 82,200

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Intangible assets, Transfer of financial assets (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Intangible Assets
Goodwill		$ 1,563,942	$ 1,002,900	$ 1,002,900
Impairment Charges	$ 0	$ 0
Minimum
Intangible Assets
Estimated useful lives of intangibles		2 years
Maximum
Intangible Assets
Estimated useful lives of intangibles		15 years
Core Deposits | Minimum
Intangible Assets
Estimated useful lives of intangibles		10 years
Core Deposits | Maximum
Intangible Assets
Estimated useful lives of intangibles		13 years
Noncompete intangibles | Minimum
Intangible Assets
Estimated useful lives of intangibles		2 years
Noncompete intangibles | Maximum
Intangible Assets
Estimated useful lives of intangibles		3 years
Client list intangibles
Intangible Assets
Estimated useful lives of intangibles		15 years

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Significant Accounting Policies
Number of active contracts	$ 1,100
Transferred at Point in Time
Summary of Significant Accounting Policies
Revenue from contract with customers	182,800	$ 104,300	$ 113,600
Transferred over Time
Summary of Significant Accounting Policies
Revenue from contract with customers	17,900	19,000	19,200
Interchange and debit card transaction fees
Summary of Significant Accounting Policies
Revenue from contract with customers	13,700	12,600	20,900
Interchange and debit card transaction fees | Before 606
Summary of Significant Accounting Policies
Transaction fees	30,200	24,500	33,000
Network costs	16,500	11,900	12,100
Trust and investment services income
Summary of Significant Accounting Policies
Revenue from contract with customers	29,437	29,244	30,229
Deposit account services
Summary of Significant Accounting Policies
Revenue from contract with customers	$ 85,700	$ 76,400	$ 82,600

Summary of Significant Accou_10

Summary of Significant Accounting Policies - Recent Accounting and Regulatory Pronouncements (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Right to use asset	$ 113,400		$ 87,400
Lease Liability	118,321		88,800
Allowance for credit losses	457,309	$ 54,400	56,927
Shareholders' equity	4,647,880		2,373,013		$ 2,366,296	$ 2,308,920
ASU 2016- 02 | Adjustment for ASU
Right to use asset				$ 82,200
Lease Liability				$ 82,200
ASU 2016-13
Allowance for credit losses		$ 54,438
ASU 2016-13 | Cumulative Effect of Adoption of ASU
Shareholders' equity	$ (44,820)
2018-15
Capitalized implementation costs related to internal use software			$ 2,900

Summary of Significant Accou_11

Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairment of goodwill	$ 0	$ 0
Impairment of other intangible		0
Additional allowance for credit losses for loans		457,309	$ 54,400	$ 56,927
Deferred tax assets		110,946		31,316
Additional reserve for unfunded commitments			6,400
Retained earnings		657,451		$ 679,895
ASU 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Additional allowance for credit losses for loans			54,438
Deferred tax assets			12,639
Additional reserve for unfunded commitments			6,400
Retained earnings		$ 44,800	$ (44,820)

Summary of Significant Accou_12

Summary of Significant Accounting Policies - Impact of ASU (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019
Assets:
Securities available-for-sale, at fair value		$ 3,330,672	$ 1,956,047
Investment Securities - Held to Maturity		955,542
Non - Acquired Loans		24,664,134	11,375,104
Allowance for credit losses	$ (54,400)	(457,309)	(56,927)
Deferred tax assets		110,946	31,316
Accrued Interest Receivable - Loans		93,900
Liabilities:
Reserve for Loan Losses - Unfunded Commitments		457,309	56,927
Equity:
Retained Earnings (Accumulated Deficit)		657,451	679,895
Credit Discount on Acquired Credit Impaired Loans	3,408
Financing Receivable, Allowance for Credit Losses	$ 54,400	457,309	56,927
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent	22.00%
Non-acquired loans
Assets:
Allowance for credit losses	$ (34,049)
Equity:
Financing Receivable, Allowance for Credit Losses	34,049
Acquired loans
Assets:
Allowance for credit losses	(16,981)
Equity:
Financing Receivable, Allowance for Credit Losses	16,981
Purchased Credit Deteriorated Loans [Member]
Assets:
Allowance for credit losses	(3,408)
Equity:
Financing Receivable, Allowance for Credit Losses	3,408
ASU 2016-13
Assets:
Acquired Loans	1,723
Allowance for credit losses	(54,438)
Deferred tax assets	12,639
Accrued Interest Receivable - Loans	1,677
Liabilities:
Reserve for Loan Losses - Unfunded Commitments	6,421
Equity:
Retained Earnings (Accumulated Deficit)	(44,820)	44,800
Financing Receivable, Allowance for Credit Losses	54,438
As previously recorded by acquiree | ASU 2016-13
Assets:
Securities available-for-sale, at fair value	1,956,047
Non - Acquired Loans	9,252,831
Acquired Loans	2,118,940
Allowance for credit losses	(111,365)
Deferred tax assets	43,955
Accrued Interest Receivable - Loans	30,009
Liabilities:
Reserve for Loan Losses - Unfunded Commitments	6,756
Equity:
Retained Earnings (Accumulated Deficit)	635,075
Financing Receivable, Allowance for Credit Losses	111,365
Adjustments
Assets:
Allowance for credit losses			(111,365)
Equity:
Financing Receivable, Allowance for Credit Losses			111,365
Adjustments | ASU 2016-13
Assets:
Securities available-for-sale, at fair value	1,956,047
Non - Acquired Loans	9,252,831
Acquired Loans	2,117,209
Allowance for credit losses	(56,927)	(109,442)	(51,030)
Deferred tax assets	31,316
Accrued Interest Receivable - Loans	28,332
Liabilities:
Reserve for Loan Losses - Unfunded Commitments	335
Equity:
Retained Earnings (Accumulated Deficit)	679,895
Financing Receivable, Allowance for Credit Losses	$ 56,927	$ 109,442	$ 51,030

Mergers and Acquisitions - CSFL

Mergers and Acquisitions - CSFL Narrative (Details) $ in Thousands	Jun. 07, 2020USD ($)shares	Dec. 31, 2020USD ($)	Jun. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Mergers and Acquisitions
Goodwill		$ 1,563,942		$ 1,563,942	$ 1,002,900	$ 1,002,900
CSFL
Mergers and Acquisitions
Shares of the common stock in exchange for each share	0.3001
Number of shares issued as consideration | shares	37,271,069
Purchase price	$ 2,256,708		$ 2,260,000
Value of the conversion of outstanding stock options and restricted stock	15,500
Purchased price decreased		$ 5,200
Stock option conversion	2,900
Loans at fair value acquired	12,950,583
Loans at fair value acquired after initial fair value adjustment	13,000,000
Estimated discount on loans	$ 239,500
Estimated discount on loans (as a percent)	1.82%
Fair value adjustment on loans acquired	$ 29,800
Loans acquired as a percentage of total loans	113.90%
Credit deficiencies that were identified as Purchased Credit Deteriorated ("PCD") loans.	$ 3,100,000
Estimated fair value of intangible asset	140,862
Goodwill	561,042
Acquisition costs				$ 83,000	$ 0
CSFL | Core Deposits
Mergers and Acquisitions
Estimated fair value of intangible asset	$ 125,900
Estimated economic life of intangible asset	10 years
Subsequent Fair Value Adjustments | CSFL
Mergers and Acquisitions
Loans at fair value acquired	$ 29,834
Estimated fair value of intangible asset	10,000
Goodwill	$ (39,441)

Mergers and Acquisitions- CSFL

Mergers and Acquisitions- CSFL (Details) - USD ($)	Jun. 07, 2020	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deposit Liabilities [Abstract]
Goodwill			$ 1,563,942,000	$ 1,002,900,000	$ 1,002,900,000
Additional information
Reversal of CSFL's ending allowance for credit losses			$ 14,602,000
Deferred tax assets related to fair value adjustments with effective tax rate			21.00%	21.00%	21.00%	35.00%
Provisional income tax expense			$ 26,600,000
Proforma amounts
Total revenues (net interest income plus noninterest income), Pro Forma			1,508,215,000	$ 1,368,452,000
Net interest income			1,047,014,000	1,058,827,000
Net adjusted income available to the common shareholder			$ 385,390,000	$ 412,515,000
EPS - basic			$ 5.44	$ 5.85
EPS - diluted			$ 5.42	$ 5.81
CSFL
Business Combination Recognized Identifiable Assets Acquired [Abstract]
Cash and cash equivalents	$ 2,566,450,000
Investment securities	1,193,910,000
Loans held for sale	453,578,000
Loans, net of allowance and mark	12,950,583,000
Premises and equipment	313,435,000	$ 330,300,000
Intangible assets	140,862,000
OREO and repossessed assets	10,009,000
Bank owned life insurance	333,053,000
Deferred tax asset.	37,239,000
Other assets	967,097,000
Total assets	18,966,216,000
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deposit Liabilities [Abstract]
Noninterest-bearing	5,291,443,000
Interest-bearing	10,332,072,000
Total deposits	15,623,515,000
Federal funds purchased and securities sold under agreements to repurchase	401,546,000
Other borrowings	271,499,000
Other liabilities	973,990,000
Total liabilities	17,270,550,000
Net identifiable assets acquired over (under) liabilities assumed	1,695,666,000
Goodwill	561,042,000
Net assets acquired over liabilities assumed	$ 2,256,708,000
Consideration:
Number of shares issued as consideration	37,271,069
Purchase price per share of the Company's common stock	$ 60.27
Company common stock issued ($2,246,327) and cash exchanged for fractional shares ($74)	$ 2,246,401,000
Stock option conversion	2,900,000
Restricted stock conversion	7,407,000
Value of common stock issued for fractional shares	2,246,327,000
Price per fractional share	74,000
Cash paid for stock options outstanding	2,900,000
Fair value of total consideration transferred	2,256,708,000	$ 2,260,000,000
Noncash Merger Related Costs	2,900,000
Merger-related charges/costs			$ 83,000,000	$ 0
Additional information
Reversal of CSFL's existing fair value adjustments	40,700,000
Adjustment to record securities at fair value (premium)	46,200,000
Reclassification of securities held as HTM to AFS	175,700,000
Total mark of the loan portfolio	$ 269,100,000
Total mark of the loan portfolio (as a percent)	2.04%
Credit mark of the loan portfolio	$ 259,700,000
Credit mark of the loan portfolio (as a percent)	1.97%
Reversal of CSFL's ending allowance for credit losses	$ 158,200,000
Fair value adjustments of allowance for credit losses	62,600,000
MTM adjustment on leased assets	4,000,000
Deminimus fixed assets written off	$ 1,600,000
Core deposit intangible from a third party valuation (as a percent)	1.28%
Core deposit intangible from a third party valuation	$ 125,900,000
Existing core deposit intangible from prior transactions that was reversed	84,900,000
Existing goodwill from prior transactions that was reversed	1,200,000,000
Reversal of prior valuation reserves	878,000
New valuation reserves	$ 1,700,000
Deferred tax assets related to fair value adjustments with effective tax rate	22.00%
Fair value adjustment of bank property held for sale	$ 3,200,000
Fair value adjustment of lease receivable	116,000
Fair value negative adjustment for investment in low income housing	3,300,000
Estimated premium for fixed maturity time deposits	20,200,000
Reversal of existing CSFL fair value adjustments related to time deposit marks from other merger transactions	546,000
Discount on TRUPs from a third party valuation	12,500,000
Reversal of the existing CSFL discount on TRUPs and other debt	5,100,000
Reversal of an existing unfunded commitment reserve at purchase date	7,100,000
Fair value adjustment to increase lease liabilities associated with rental facilities	2,500,000
Fair value adjustments to employee benefit plans	5,200,000
Merger-related charges/costs			83,000,000	$ 0
Provision for loan losses			3,800,000
Provisional income tax expense			$ 119,100,000
CSFL | As Recorded by CSFL
Business Combination Recognized Identifiable Assets Acquired [Abstract]
Cash and cash equivalents	2,566,450,000
Investment securities	1,188,403,000
Loans held for sale	453,578,000
Loans, net of allowance and mark	12,969,091,000
Premises and equipment	308,150,000
Intangible assets	1,294,211,000
OREO and repossessed assets	10,849,000
Bank owned life insurance	333,053,000
Deferred tax asset.	54,123,000
Other assets	967,059,000
Total assets	20,144,967,000
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deposit Liabilities [Abstract]
Noninterest-bearing	5,291,443,000
Interest-bearing	10,312,370,000
Total deposits	15,603,813,000
Federal funds purchased and securities sold under agreements to repurchase	401,546,000
Other borrowings	278,900,000
Other liabilities	977,725,000
Total liabilities	17,261,984,000
Net identifiable assets acquired over (under) liabilities assumed	2,882,983,000
Net assets acquired over liabilities assumed	2,882,983,000
CSFL | Initial Fair Value Adjustments
Business Combination Recognized Identifiable Assets Acquired [Abstract]
Investment securities	5,507,000
Loans, net of allowance and mark	(48,342,000)
Premises and equipment	2,392,000
Intangible assets	(1,163,349,000)
OREO and repossessed assets	(791,000)
Deferred tax asset.	(8,681,000)
Other assets	(604,000)
Total assets	(1,213,868,000)
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deposit Liabilities [Abstract]
Interest-bearing	19,702,000
Total deposits	19,702,000
Other borrowings	(7,401,000)
Other liabilities	(4,592,000)
Total liabilities	7,709,000
Net identifiable assets acquired over (under) liabilities assumed	(1,221,577,000)
Goodwill	600,483,000
Net assets acquired over liabilities assumed	(621,094,000)
CSFL | Subsequent Fair Value Adjustments
Business Combination Recognized Identifiable Assets Acquired [Abstract]
Loans, net of allowance and mark	29,834,000
Premises and equipment	2,893,000
Intangible assets	10,000,000
OREO and repossessed assets	(49,000)
Deferred tax asset.	(8,203,000)
Other assets	642,000
Total assets	35,117,000
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deposit Liabilities [Abstract]
Other liabilities	857,000
Total liabilities	857,000
Net identifiable assets acquired over (under) liabilities assumed	34,260,000
Goodwill	(39,441,000)
Net assets acquired over liabilities assumed	$ (5,181,000)
Additional information
Deferred tax assets related to fair value adjustments with effective tax rate	23.78%
CSFL | Subsequent Fair Value Adjustments
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Deposit Liabilities [Abstract]
Other liabilities	$ 857,000

Trading Securities (Details)

Trading Securities (Details) - USD ($)	Jul. 07, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Trading Securities
Purchases	$ 201,095,000	$ (201,095,000)
Proceeds from sale	190,907,000	(190,907,000)
Net realized gain	338,000	$ 50,000	$ 2,711,000	$ (655,000)
Net unrealized gains	148,000
Ending balance	$ 10,674,000

Investment Securities - Amortiz

Investment Securities - Amortized cost and fair value for available for sale securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment securities available for sale
Amortized cost	$ 3,268,037	$ 1,940,763
Gross Unrealized Gains	66,800	19,823
Gross Unrealized Losses	(4,165)	(4,539)
Fair Value	3,330,672	1,956,047
Gross realized gains	662	6,030	$ 31
Gross realized losses	612	3,319	$ 686
investment securities held-to-maturity
Investment Securities - Held to Maturity	955,542
Gross Unrealized Gains	2,764
Gross Unrealized Losses	(1,123)
Fair Value	957,183	0
Government-sponsored entities debt
Investment securities available for sale
Amortized cost	29,882	25,356
Gross Unrealized Gains	16	585
Gross Unrealized Losses	(642)
Fair Value	29,256	25,941
investment securities held-to-maturity
Investment Securities - Held to Maturity	25,000
Gross Unrealized Gains	1
Fair Value	25,001
State and municipal obligations
Investment securities available for sale
Amortized cost	502,575	204,150
Gross Unrealized Gains	17,491	5,029
Gross Unrealized Losses	(27)	(764)
Fair Value	520,039	208,415
Mortgage-backed securities
Investment securities available for sale
Amortized cost	2,722,018	1,711,257
Gross Unrealized Gains	49,153	14,209
Gross Unrealized Losses	(3,496)	(3,775)
Fair Value	2,767,675	$ 1,721,691
investment securities held-to-maturity
Investment Securities - Held to Maturity	930,542
Gross Unrealized Gains	2,763
Gross Unrealized Losses	(1,123)
Fair Value	932,182
Corporate securities.
Investment securities available for sale
Amortized cost	13,562
Gross Unrealized Gains	140
Fair Value	13,702
Mortgage-backed securities issued by private label holdings
Investment securities available for sale
Fair Value	$ 0

Investment Securities - Carryin

Investment Securities - Carrying value of other investment securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2018	Dec. 31, 2019
Other investment securities
Carrying Value	$ 160,443		$ 49,124
Impairment on other investment securities	0	$ (991)
Federal Home Loan Bank stock
Other investment securities
Carrying Value	15,083		43,044
Federal Reserve Bank Stock
Other investment securities
Carrying Value	129,871
Investment in unconsolidated subsidiaries
Other investment securities
Carrying Value	4,941		3,563
Other nonmarketable investment securities
Other investment securities
Carrying Value	$ 10,548		$ 2,517

Investment Securities - Amort_2

Investment Securities - Amortized cost and fair value by contractual maturity (Details) - USD ($)	Jul. 07, 2020	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amortized Cost
Due after five years through ten years			$ 88,735,000
Due after ten years			866,807,000
Total			955,542,000
Fair Value
Due after five years through ten years			89,007,000
Due after ten years			868,176,000
Fair Value			957,183,000	$ 0
Amortized Cost
Due in one year or less			9,669,000
Due after one year through five years			80,846,000
Due after five years through ten years			525,547,000
Due after ten years			2,651,975,000
Amortized Cost			3,268,037,000	1,940,763,000
Fair Value
Due in one year or less			9,698,000
Due after one year through five years			83,586,000
Due after five years through ten years			539,905,000
Due after ten years			2,697,483,000
Fair Value			3,330,672,000	1,956,047,000
Information with respect to sales of available-for-sale securities
Sale proceeds			100,754,000	242,733,000	$ 73,054,000
Gross realized gains			662,000	6,030,000	31,000
Gross realized losses			612,000	3,319,000	686,000
Net realized gain	$ 338,000		50,000	2,711,000	(655,000)
Information with respect to sales of held-to-maturity
Proceeds from sales of investment securities held to maturity			$ 0	0	$ 0
VISA Class B Shares
Information with respect to sales of available-for-sale securities
Net realized gain		$ 5,400,000		$ 2,700,000

Investment Securities - Securit

Investment Securities - Securities with gross unrealized losses (Details) $ in Thousands	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)
Investment Securities
Number of securities with gross unrealized loss | item	86
Securities Available for Sale, Gross Unrealized Losses
Less Than Twelve Months	$ 3,144	$ 3,186
Twelve Months or More	1,021	1,353
Securities Available for Sale, Fair Value
Less Than Twelve Months	542,297	503,728
Twelve Months or More	105,125	141,982
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less Than Twelve Months	1,123
Securities Held to Maturity, Fair Value
Less Than Twelve Months	240,591
Government-sponsored entities debt
Securities Available for Sale, Gross Unrealized Losses
Less Than Twelve Months	642
Securities Available for Sale, Fair Value
Less Than Twelve Months	24,358
State and municipal obligations
Securities Available for Sale, Gross Unrealized Losses
Less Than Twelve Months	27	764
Securities Available for Sale, Fair Value
Less Than Twelve Months	8,620	42,070
Mortgage-backed securities
Securities Available for Sale, Gross Unrealized Losses
Less Than Twelve Months	2,475	2,422
Twelve Months or More	1,021	1,353
Securities Available for Sale, Fair Value
Less Than Twelve Months	509,319	461,658
Twelve Months or More	105,125	$ 141,982
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less Than Twelve Months	1,123
Securities Held to Maturity, Fair Value
Less Than Twelve Months	$ 240,591

Investment Securities - Additio

Investment Securities - Additional disclosures (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Additional disclosures
Carrying value of investment securities pledged to secure public funds deposits and for other purposes required and permitted by law	$ 2.1	$ 726.1
Carrying amount of the securities pledged to collateralize repurchase agreements	$ 515.9	$ 242.2

Loans - Summary of loans (Detai

Loans - Summary of loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Loans
Total loans - ASU 2016-13	$ 24,664,134
Total loans	24,664,134	$ 11,375,104
Less allowance for credit losses	(457,309)	(56,927)
Loans, net	24,206,825	11,313,113
Deferred fees	35,600
Accrued interest receivable (AIR)	93,900
Acquired credit impaired loans
Summary of Loans
Total loans - ASU 2016-13		361,846
Total loans		361,846	$ 489,723
Less allowance for credit losses		(5,064)
Loans, net		356,782
Previous Accounting Guidance [Member]
Summary of Loans
Less allowance for credit losses		(61,991)
Unamortized Discounts	97,700
Construction and land development
Summary of Loans
Total loans - ASU 2016-13	1,899,066
Construction and land development | Acquired credit impaired loans
Summary of Loans
Total loans		25,032	32,942
Commercial non-owner occupied
Summary of Loans
Total loans - ASU 2016-13	5,931,323
Consumer Owner Occupied Loans
Summary of Loans
Total loans - ASU 2016-13	4,108,042
Home equity loans
Summary of Loans
Total loans - ASU 2016-13	1,336,689
Commercial owner occupied real estate loan
Summary of Loans
Total loans - ASU 2016-13	4,842,092
Commercial and industrial
Summary of Loans
Total loans - ASU 2016-13	5,047,147
Commercial and industrial | Acquired credit impaired loans
Summary of Loans
Total loans		7,029	10,043
Other income producing property
Summary of Loans
Total loans - ASU 2016-13	587,448
Consumer
Summary of Loans
Total loans - ASU 2016-13	894,334
Consumer | Acquired credit impaired loans
Summary of Loans
Total loans		35,488	42,492
Other loans
Summary of Loans
Total loans - ASU 2016-13	17,993
Commercial loans
Summary of Loans
Total loans - ASU 2016-13	17,657,996
Commercial loans | Acquired credit impaired loans
Summary of Loans
Total loans - ASU 2016-13		7,029
Commercial loans | Construction and land development
Summary of Loans
Total loans - ASU 2016-13	1,238,265
Total loans	1,899,066	1,017,261
Commercial loans | Construction and land development | Acquired credit impaired loans
Summary of Loans
Total loans - ASU 2016-13		25,032
Total loans		25,032
Commercial loans | Commercial non-owner occupied
Summary of Loans
Total loans - ASU 2016-13	5,931,323
Total loans	5,931,323	2,323,967
Commercial loans | Commercial non-owner occupied | Acquired credit impaired loans
Summary of Loans
Total loans - ASU 2016-13		130,938
Commercial loans | Commercial non-owner occupied real estate
Summary of Loans
Total loans	4,842,092	2,158,701
Commercial loans | Consumer Owner Occupied Loans
Summary of Loans
Total loans - ASU 2016-13	35,137
Commercial loans | Real estate | Acquired credit impaired loans
Summary of Loans
Total loans		130,938	196,764
Commercial loans | Commercial owner occupied real estate loan
Summary of Loans
Total loans - ASU 2016-13	4,842,092
Commercial loans | Commercial and industrial
Summary of Loans
Total loans - ASU 2016-13	5,047,147
Total loans	5,047,147	1,386,327
Commercial loans | Commercial and industrial | Acquired credit impaired loans
Summary of Loans
Total loans		7,029
Commercial loans | Other income producing property
Summary of Loans
Total loans - ASU 2016-13	546,039
Total loans	587,448	346,554
Commercial loans | Other loans
Summary of Loans
Total loans - ASU 2016-13	17,993
Consumer
Summary of Loans
Total loans - ASU 2016-13	7,006,138
Consumer | Acquired credit impaired loans
Summary of Loans
Total loans - ASU 2016-13		35,488
Consumer | Construction and land development
Summary of Loans
Total loans - ASU 2016-13	660,801
Consumer | Consumer Owner Occupied Loans
Summary of Loans
Total loans - ASU 2016-13	4,072,905
Total loans	4,108,042	2,706,960
Consumer | Home equity loans
Summary of Loans
Total loans - ASU 2016-13	1,336,689
Total loans	1,336,689	758,020
Consumer | Real estate | Acquired credit impaired loans
Summary of Loans
Total loans		163,359	$ 207,482
Consumer | Commercial and industrial | Acquired credit impaired loans
Summary of Loans
Total loans		7,029
Consumer | Other income producing property
Summary of Loans
Total loans - ASU 2016-13	41,409
Consumer | Consumer
Summary of Loans
Total loans - ASU 2016-13	894,334
Total loans	894,334	663,422
Consumer | Consumer | Acquired credit impaired loans
Summary of Loans
Total loans		35,488
Consumer | Other loans
Summary of Loans
Total loans	$ 17,993	$ 13,892

Loans - Summary of non-acquired

Loans - Summary of non-acquired loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Loans
Total loans	$ 24,664,134	$ 11,375,104
Less allowance for credit losses	(457,309)	(56,927)
Loans, net	24,206,825	11,313,113
Commercial loans | Construction and land development
Summary of Loans
Total loans	1,899,066	1,017,261
Commercial loans | Commercial non-owner occupied
Summary of Loans
Total loans	5,931,323	2,323,967
Commercial loans | Commercial non-owner occupied real estate
Summary of Loans
Total loans	4,842,092	2,158,701
Commercial loans | Commercial and industrial
Summary of Loans
Total loans	5,047,147	1,386,327
Commercial loans | Other income producing property
Summary of Loans
Total loans	587,448	346,554
Consumer | Consumer Owner Occupied Loans
Summary of Loans
Total loans	4,108,042	2,706,960
Consumer | Home equity loans
Summary of Loans
Total loans	1,336,689	758,020
Consumer | Consumer
Summary of Loans
Total loans	894,334	663,422
Consumer | Other loans
Summary of Loans
Total loans	$ 17,993	13,892
Non-acquired loans
Summary of Loans
Total loans		9,252,831	$ 7,933,286
Less allowance for credit losses		(56,927)
Loans, net		9,195,904
Non-acquired loans | Construction and land development
Summary of Loans
Total loans		968,360	841,445
Non-acquired loans | Commercial non-owner occupied
Summary of Loans
Total loans		1,811,138	1,415,551
Non-acquired loans | Consumer Owner Occupied Loans
Summary of Loans
Total loans		2,118,839	1,936,265
Non-acquired loans | Home equity loans
Summary of Loans
Total loans		518,628	495,148
Non-acquired loans | Commercial owner occupied real estate loan
Summary of Loans
Total loans		1,784,017	1,517,551
Non-acquired loans | Commercial and industrial
Summary of Loans
Total loans		1,280,859	1,054,952
Non-acquired loans | Other income producing property
Summary of Loans
Total loans		218,617	214,353
Non-acquired loans | Consumer
Summary of Loans
Total loans		538,481	448,664
Non-acquired loans | Other loans
Summary of Loans
Total loans		13,892	$ 9,357
Non-acquired loans | Commercial loans
Summary of Loans
Total loans		6,062,991
Non-acquired loans | Commercial loans | Construction and land development
Summary of Loans
Total loans		968,360
Non-acquired loans | Commercial loans | Commercial non-owner occupied
Summary of Loans
Total loans		1,811,138
Non-acquired loans | Commercial loans | Commercial non-owner occupied real estate
Summary of Loans
Total loans		2,779,498
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan
Summary of Loans
Total loans		1,784,017
Non-acquired loans | Commercial loans | Commercial and industrial
Summary of Loans
Total loans		1,280,859
Non-acquired loans | Commercial loans | Other income producing property
Summary of Loans
Total loans		218,617
Non-acquired loans | Consumer
Summary of Loans
Total loans		3,189,840
Non-acquired loans | Consumer | Consumer Owner Occupied Loans
Summary of Loans
Total loans		2,118,839
Non-acquired loans | Consumer | Home equity loans
Summary of Loans
Total loans		518,628
Non-acquired loans | Consumer | Real estate
Summary of Loans
Total loans		2,637,467
Non-acquired loans | Consumer | Consumer
Summary of Loans
Total loans		538,481
Non-acquired loans | Consumer | Other loans
Summary of Loans
Total loans		$ 13,892

Loans - Summary of Acquired non

Loans - Summary of Acquired non-credit impaired loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Loans
Total loans	$ 24,664,134	$ 11,375,104
Commercial loans | Construction and land development
Summary of Loans
Total loans	1,899,066	1,017,261
Commercial loans | Commercial non-owner occupied
Summary of Loans
Total loans	5,931,323	2,323,967
Commercial loans | Commercial non-owner occupied real estate
Summary of Loans
Total loans	4,842,092	2,158,701
Commercial loans | Commercial and industrial
Summary of Loans
Total loans	5,047,147	1,386,327
Commercial loans | Other income producing property
Summary of Loans
Total loans	587,448	346,554
Consumer | Consumer Owner Occupied Loans
Summary of Loans
Total loans	4,108,042	2,706,960
Consumer | Home equity loans
Summary of Loans
Total loans	1,336,689	758,020
Consumer | Consumer
Summary of Loans
Total loans	894,334	663,422
Consumer | Other loans
Summary of Loans
Total loans	$ 17,993	13,892
Acquired non-credit impaired loans
Summary of Loans
Total loans		1,760,427	$ 2,594,826
Unamortized Discounts		20,300
Acquired non-credit impaired loans | Construction and land development
Summary of Loans
Total loans		33,569	165,070
Acquired non-credit impaired loans | Commercial non-owner occupied
Summary of Loans
Total loans		447,441	679,253
Acquired non-credit impaired loans | Consumer Owner Occupied Loans
Summary of Loans
Total loans		496,431	628,813
Acquired non-credit impaired loans | Home equity loans
Summary of Loans
Total loans		188,732	242,425
Acquired non-credit impaired loans | Commercial owner occupied real estate loan
Summary of Loans
Total loans		307,193	421,841
Acquired non-credit impaired loans | Commercial and industrial
Summary of Loans
Total loans		101,880	212,537
Acquired non-credit impaired loans | Other income producing property
Summary of Loans
Total loans		95,697	133,110
Acquired non-credit impaired loans | Consumer
Summary of Loans
Total loans		89,484	$ 111,777
Acquired non-credit impaired loans | Commercial loans
Summary of Loans
Total loans		985,780
Acquired non-credit impaired loans | Commercial loans | Construction and land development
Summary of Loans
Total loans		33,569
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied
Summary of Loans
Total loans		447,441
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied real estate
Summary of Loans
Total loans		481,010
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan
Summary of Loans
Total loans		307,193
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial
Summary of Loans
Total loans		101,880
Acquired non-credit impaired loans | Commercial loans | Other income producing property
Summary of Loans
Total loans		95,697
Acquired non-credit impaired loans | Consumer
Summary of Loans
Total loans		774,647
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans
Summary of Loans
Total loans		496,431
Acquired non-credit impaired loans | Consumer | Home equity loans
Summary of Loans
Total loans		188,732
Acquired non-credit impaired loans | Consumer | Real estate
Summary of Loans
Total loans		685,163
Acquired non-credit impaired loans | Consumer | Consumer
Summary of Loans
Total loans		$ 89,484

Loans - Credit impaired loans (

Loans - Credit impaired loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Loans
Total loans	$ 24,664,134	$ 11,375,104
Less allowance for credit losses	(457,309)	(56,927)
Loans, net	24,206,825	11,313,113
Commercial loans | Construction and land development
Summary of Loans
Total loans	1,899,066	1,017,261
Commercial loans | Commercial and industrial
Summary of Loans
Total loans	5,047,147	1,386,327
Consumer | Consumer
Summary of Loans
Total loans	$ 894,334	663,422
Acquired credit impaired loans
Summary of Loans
Total loans		361,846	$ 489,723
Less allowance for credit losses		(5,064)
Loans, net		356,782
Acquired credit impaired loans | Construction and land development
Summary of Loans
Total loans		25,032	32,942
Acquired credit impaired loans | Consumer
Summary of Loans
Total loans		35,488	42,492
Acquired credit impaired loans | Commercial and industrial
Summary of Loans
Total loans		7,029	10,043
Acquired credit impaired loans | Commercial loans | Real estate
Summary of Loans
Total loans		130,938	196,764
Acquired credit impaired loans | Commercial loans | Construction and land development
Summary of Loans
Total loans		25,032
Acquired credit impaired loans | Commercial loans | Commercial and industrial
Summary of Loans
Total loans		7,029
Acquired credit impaired loans | Consumer | Real estate
Summary of Loans
Total loans		163,359	$ 207,482
Acquired credit impaired loans | Consumer | Consumer
Summary of Loans
Total loans		35,488
Acquired credit impaired loans | Consumer | Commercial and industrial
Summary of Loans
Total loans		$ 7,029

Loans - Loans purchased through

Loans - Loans purchased through its acquisition of CSB (Details) - CSFL $ in Thousands	Jun. 07, 2020USD ($)
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Book value of acquired loans at acquisition	$ 3,091,264
Less allowance for loan losses	(149,404)
Non-accretable difference	(14,283)
Acquired loans, net	$ 2,927,577

Loans - Carrying values of acqu

Loans - Carrying values of acquired credit impaired loans (Details) - Acquired credit impaired loans - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Contractual loan payments receivable, estimates of amounts not expected to be collected, other fair value adjustments and the resulting fair values of acquired loans
Contractual principal and interest	$ 452,818
Non-accretable difference	(13,938)
Cash flows expected to be collected	438,880
Accretable Yield	(82,098)
Acquired loans, net	$ 356,782	$ 485,119

Loans - Changes in the carrying

Loans - Changes in the carrying value of acquired credit impaired loans (Details) - Acquired credit impaired loans $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Changes in the carrying value of acquired loans at the acquisition date
Balance at the beginning of the period	$ 485,119
Net reductions for payments, foreclosures, and accretion	(127,877)
Change in the allowance for loan losses on acquired loans	(460)
Balance at the end of the period	$ 356,782

Loans - Accretable yield balanc

Loans - Accretable yield balance for acquired credit impaired loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Changes in the carrying amount of accretable difference for acquired impaired and non-impaired loans
Decline in accretable yield balance	$ 34,700
Acquired credit impaired loans
Changes in the carrying amount of accretable difference for acquired impaired and non-impaired loans
Balance at beginning of period	116,754	$ 133,096
Park Sterling Corporation ("Park Sterling") acquisition Day 1 adjustment		(1,460)
Contractual interest income	(26,515)	(33,115)
Accretion on acquired credit impaired loans	(17,813)	(19,004)
Reclass of nonaccretable difference due to improvement in expected cash flows	9,826	37,501
Other changes, net	(154)	(264)
Balance at end of period	82,098	116,754
Accretion income	44,300
Improved expected cash flows	9,800
Contractual principal and interest	452,818
Acquired non-credit impaired loans accounted under FASB 310 20
Changes in the carrying amount of accretable difference for acquired impaired and non-impaired loans
After fair value adjustment	1,800,000
Acquired loans accounted under FASB ASC 310 20
Changes in the carrying amount of accretable difference for acquired impaired and non-impaired loans
Contractual principal and interest	1,800,000	2,600,000
After fair value adjustment		2,600,000
Fair value adjustment	$ 20,300	$ 33,400

Loans - Credit risk profile by

Loans - Credit risk profile by risk grade of commercial loans (Details) $ in Thousands	Dec. 31, 2020USD ($)
Loans
Amortized Cost Basis by Origination Year - 2020	$ 6,483,423
Amortized Cost Basis by Origination Year - 2019	4,366,628
Amortized Cost Basis by Origination Year - 2018	3,114,428
Amortized Cost Basis by Origination Year - 2017	2,432,489
Amortized Cost Basis by Origination Year - 2016	2,027,572
Amortized Cost Basis by Origination Year - Prior	4,529,178
Amortized Cost Basis by Origination Year - Revolving	1,710,416
Total loans - ASU 2016-13	24,664,134
Construction and land development
Loans
Total loans - ASU 2016-13	1,899,066
Commercial non-owner occupied
Loans
Total loans - ASU 2016-13	5,931,323
Commercial owner occupied real estate loan
Loans
Total loans - ASU 2016-13	4,842,092
Commercial and industrial
Loans
Total loans - ASU 2016-13	5,047,147
Other income producing property
Loans
Total loans - ASU 2016-13	587,448
Consumer Owner Occupied Loans
Loans
Total loans - ASU 2016-13	4,108,042
Home equity loans
Loans
Total loans - ASU 2016-13	1,336,689
Consumer
Loans
Total loans - ASU 2016-13	894,334
Other loans
Loans
Total loans - ASU 2016-13	17,993
Commercial loans
Loans
Amortized Cost Basis by Origination Year - 2020	4,989,940
Amortized Cost Basis by Origination Year - 2019	3,304,179
Amortized Cost Basis by Origination Year - 2018	2,376,878
Amortized Cost Basis by Origination Year - 2017	1,834,295
Amortized Cost Basis by Origination Year - 2016	1,582,367
Amortized Cost Basis by Origination Year - Prior	3,173,267
Amortized Cost Basis by Origination Year - Revolving	397,070
Total loans - ASU 2016-13	17,657,996
Commercial loans | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	4,906,233
Amortized Cost Basis by Origination Year - 2019	3,138,214
Amortized Cost Basis by Origination Year - 2018	2,226,410
Amortized Cost Basis by Origination Year - 2017	1,708,578
Amortized Cost Basis by Origination Year - 2016	1,466,937
Amortized Cost Basis by Origination Year - Prior	2,834,164
Amortized Cost Basis by Origination Year - Revolving	384,920
Total loans - ASU 2016-13	16,665,456
Commercial loans | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	74,706
Amortized Cost Basis by Origination Year - 2019	106,813
Amortized Cost Basis by Origination Year - 2018	130,176
Amortized Cost Basis by Origination Year - 2017	68,544
Amortized Cost Basis by Origination Year - 2016	57,424
Amortized Cost Basis by Origination Year - Prior	224,136
Amortized Cost Basis by Origination Year - Revolving	9,827
Total loans - ASU 2016-13	671,626
Commercial loans | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	9,000
Amortized Cost Basis by Origination Year - 2019	59,150
Amortized Cost Basis by Origination Year - 2018	20,291
Amortized Cost Basis by Origination Year - 2017	57,170
Amortized Cost Basis by Origination Year - 2016	58,003
Amortized Cost Basis by Origination Year - Prior	114,943
Amortized Cost Basis by Origination Year - Revolving	2,323
Total loans - ASU 2016-13	320,880
Commercial loans | Doubtful
Loans
Amortized Cost Basis by Origination Year - 2020	1
Amortized Cost Basis by Origination Year - 2019	2
Amortized Cost Basis by Origination Year - 2018	1
Amortized Cost Basis by Origination Year - 2017	3
Amortized Cost Basis by Origination Year - 2016	3
Amortized Cost Basis by Origination Year - Prior	24
Total loans - ASU 2016-13	34
Commercial loans | Construction and land development
Loans
Amortized Cost Basis by Origination Year - 2020	478,734
Amortized Cost Basis by Origination Year - 2019	418,543
Amortized Cost Basis by Origination Year - 2018	135,189
Amortized Cost Basis by Origination Year - 2017	83,189
Amortized Cost Basis by Origination Year - 2016	43,034
Amortized Cost Basis by Origination Year - Prior	64,074
Amortized Cost Basis by Origination Year - Revolving	15,502
Total loans - ASU 2016-13	1,238,265
Commercial loans | Construction and land development | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	457,433
Amortized Cost Basis by Origination Year - 2019	410,075
Amortized Cost Basis by Origination Year - 2018	133,719
Amortized Cost Basis by Origination Year - 2017	79,345
Amortized Cost Basis by Origination Year - 2016	41,018
Amortized Cost Basis by Origination Year - Prior	53,104
Amortized Cost Basis by Origination Year - Revolving	15,502
Total loans - ASU 2016-13	1,190,196
Commercial loans | Construction and land development | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	20,912
Amortized Cost Basis by Origination Year - 2019	5,668
Amortized Cost Basis by Origination Year - 2018	707
Amortized Cost Basis by Origination Year - 2017	1,757
Amortized Cost Basis by Origination Year - 2016	1,815
Amortized Cost Basis by Origination Year - Prior	7,293
Total loans - ASU 2016-13	38,152
Commercial loans | Construction and land development | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	389
Amortized Cost Basis by Origination Year - 2019	2,800
Amortized Cost Basis by Origination Year - 2018	763
Amortized Cost Basis by Origination Year - 2017	2,087
Amortized Cost Basis by Origination Year - 2016	201
Amortized Cost Basis by Origination Year - Prior	3,669
Total loans - ASU 2016-13	9,909
Commercial loans | Construction and land development | Doubtful
Loans
Amortized Cost Basis by Origination Year - Prior	8
Total loans - ASU 2016-13	8
Commercial loans | Commercial non-owner occupied
Loans
Amortized Cost Basis by Origination Year - 2020	843,018
Amortized Cost Basis by Origination Year - 2019	1,208,794
Amortized Cost Basis by Origination Year - 2018	963,951
Amortized Cost Basis by Origination Year - 2017	733,106
Amortized Cost Basis by Origination Year - 2016	754,149
Amortized Cost Basis by Origination Year - Prior	1,370,284
Amortized Cost Basis by Origination Year - Revolving	58,021
Total loans - ASU 2016-13	5,931,323
Commercial loans | Commercial non-owner occupied | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	799,175
Amortized Cost Basis by Origination Year - 2019	1,082,242
Amortized Cost Basis by Origination Year - 2018	844,988
Amortized Cost Basis by Origination Year - 2017	661,092
Amortized Cost Basis by Origination Year - 2016	676,895
Amortized Cost Basis by Origination Year - Prior	1,196,156
Amortized Cost Basis by Origination Year - Revolving	58,021
Total loans - ASU 2016-13	5,318,569
Commercial loans | Commercial non-owner occupied | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	42,492
Amortized Cost Basis by Origination Year - 2019	76,890
Amortized Cost Basis by Origination Year - 2018	111,466
Amortized Cost Basis by Origination Year - 2017	44,790
Amortized Cost Basis by Origination Year - 2016	38,637
Amortized Cost Basis by Origination Year - Prior	131,015
Total loans - ASU 2016-13	445,290
Commercial loans | Commercial non-owner occupied | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	1,351
Amortized Cost Basis by Origination Year - 2019	49,662
Amortized Cost Basis by Origination Year - 2018	7,497
Amortized Cost Basis by Origination Year - 2017	27,224
Amortized Cost Basis by Origination Year - 2016	38,617
Amortized Cost Basis by Origination Year - Prior	43,109
Total loans - ASU 2016-13	167,460
Commercial loans | Commercial non-owner occupied | Doubtful
Loans
Amortized Cost Basis by Origination Year - Prior	4
Total loans - ASU 2016-13	4
Commercial loans | Commercial owner occupied real estate loan
Loans
Amortized Cost Basis by Origination Year - 2020	817,915
Amortized Cost Basis by Origination Year - 2019	977,581
Amortized Cost Basis by Origination Year - 2018	739,519
Amortized Cost Basis by Origination Year - 2017	638,364
Amortized Cost Basis by Origination Year - 2016	486,755
Amortized Cost Basis by Origination Year - Prior	1,139,662
Amortized Cost Basis by Origination Year - Revolving	42,296
Total loans - ASU 2016-13	4,842,092
Commercial loans | Commercial owner occupied real estate loan | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	805,192
Amortized Cost Basis by Origination Year - 2019	957,412
Amortized Cost Basis by Origination Year - 2018	721,808
Amortized Cost Basis by Origination Year - 2017	603,785
Amortized Cost Basis by Origination Year - 2016	458,065
Amortized Cost Basis by Origination Year - Prior	1,042,755
Amortized Cost Basis by Origination Year - Revolving	42,239
Total loans - ASU 2016-13	4,631,256
Commercial loans | Commercial owner occupied real estate loan | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	6,993
Amortized Cost Basis by Origination Year - 2019	15,984
Amortized Cost Basis by Origination Year - 2018	13,021
Amortized Cost Basis by Origination Year - 2017	14,457
Amortized Cost Basis by Origination Year - 2016	13,597
Amortized Cost Basis by Origination Year - Prior	48,775
Amortized Cost Basis by Origination Year - Revolving	21
Total loans - ASU 2016-13	112,848
Commercial loans | Commercial owner occupied real estate loan | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	5,729
Amortized Cost Basis by Origination Year - 2019	4,185
Amortized Cost Basis by Origination Year - 2018	4,690
Amortized Cost Basis by Origination Year - 2017	20,122
Amortized Cost Basis by Origination Year - 2016	15,093
Amortized Cost Basis by Origination Year - Prior	48,127
Amortized Cost Basis by Origination Year - Revolving	36
Total loans - ASU 2016-13	97,982
Commercial loans | Commercial owner occupied real estate loan | Doubtful
Loans
Amortized Cost Basis by Origination Year - 2020	1
Amortized Cost Basis by Origination Year - Prior	5
Total loans - ASU 2016-13	6
Commercial loans | Commercial and industrial
Loans
Amortized Cost Basis by Origination Year - 2020	2,725,233
Amortized Cost Basis by Origination Year - 2019	599,655
Amortized Cost Basis by Origination Year - 2018	459,472
Amortized Cost Basis by Origination Year - 2017	323,878
Amortized Cost Basis by Origination Year - 2016	228,839
Amortized Cost Basis by Origination Year - Prior	451,293
Amortized Cost Basis by Origination Year - Revolving	258,777
Total loans - ASU 2016-13	5,047,147
Commercial loans | Commercial and industrial | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	2,723,320
Amortized Cost Basis by Origination Year - 2019	595,310
Amortized Cost Basis by Origination Year - 2018	450,238
Amortized Cost Basis by Origination Year - 2017	308,914
Amortized Cost Basis by Origination Year - 2016	223,532
Amortized Cost Basis by Origination Year - Prior	419,555
Amortized Cost Basis by Origination Year - Revolving	247,169
Total loans - ASU 2016-13	4,968,038
Commercial loans | Commercial and industrial | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	1,566
Amortized Cost Basis by Origination Year - 2019	3,273
Amortized Cost Basis by Origination Year - 2018	3,031
Amortized Cost Basis by Origination Year - 2017	7,243
Amortized Cost Basis by Origination Year - 2016	2,496
Amortized Cost Basis by Origination Year - Prior	25,727
Amortized Cost Basis by Origination Year - Revolving	9,368
Total loans - ASU 2016-13	52,704
Commercial loans | Commercial and industrial | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	347
Amortized Cost Basis by Origination Year - 2019	1,070
Amortized Cost Basis by Origination Year - 2018	6,202
Amortized Cost Basis by Origination Year - 2017	7,718
Amortized Cost Basis by Origination Year - 2016	2,808
Amortized Cost Basis by Origination Year - Prior	6,010
Amortized Cost Basis by Origination Year - Revolving	2,240
Total loans - ASU 2016-13	26,395
Commercial loans | Commercial and industrial | Doubtful
Loans
Amortized Cost Basis by Origination Year - 2019	2
Amortized Cost Basis by Origination Year - 2018	1
Amortized Cost Basis by Origination Year - 2017	3
Amortized Cost Basis by Origination Year - 2016	3
Amortized Cost Basis by Origination Year - Prior	1
Total loans - ASU 2016-13	10
Commercial loans | Other income producing property
Loans
Amortized Cost Basis by Origination Year - 2020	99,214
Amortized Cost Basis by Origination Year - 2019	92,111
Amortized Cost Basis by Origination Year - 2018	78,000
Amortized Cost Basis by Origination Year - 2017	55,357
Amortized Cost Basis by Origination Year - 2016	68,509
Amortized Cost Basis by Origination Year - Prior	146,214
Amortized Cost Basis by Origination Year - Revolving	6,634
Total loans - ASU 2016-13	546,039
Commercial loans | Other income producing property | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	95,530
Amortized Cost Basis by Origination Year - 2019	89,648
Amortized Cost Basis by Origination Year - 2018	75,301
Amortized Cost Basis by Origination Year - 2017	55,103
Amortized Cost Basis by Origination Year - 2016	66,351
Amortized Cost Basis by Origination Year - Prior	121,304
Amortized Cost Basis by Origination Year - Revolving	6,487
Total loans - ASU 2016-13	509,724
Commercial loans | Other income producing property | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	2,613
Amortized Cost Basis by Origination Year - 2019	1,417
Amortized Cost Basis by Origination Year - 2018	1,702
Amortized Cost Basis by Origination Year - 2017	235
Amortized Cost Basis by Origination Year - 2016	879
Amortized Cost Basis by Origination Year - Prior	11,202
Amortized Cost Basis by Origination Year - Revolving	100
Total loans - ASU 2016-13	18,148
Commercial loans | Other income producing property | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	1,071
Amortized Cost Basis by Origination Year - 2019	1,046
Amortized Cost Basis by Origination Year - 2018	997
Amortized Cost Basis by Origination Year - 2017	19
Amortized Cost Basis by Origination Year - 2016	1,279
Amortized Cost Basis by Origination Year - Prior	13,702
Amortized Cost Basis by Origination Year - Revolving	47
Total loans - ASU 2016-13	18,161
Commercial loans | Other income producing property | Doubtful
Loans
Amortized Cost Basis by Origination Year - Prior	6
Total loans - ASU 2016-13	6
Commercial loans | Consumer Owner Occupied Loans
Loans
Amortized Cost Basis by Origination Year - 2020	7,833
Amortized Cost Basis by Origination Year - 2019	7,495
Amortized Cost Basis by Origination Year - 2018	747
Amortized Cost Basis by Origination Year - 2017	401
Amortized Cost Basis by Origination Year - 2016	1,081
Amortized Cost Basis by Origination Year - Prior	1,740
Amortized Cost Basis by Origination Year - Revolving	15,840
Total loans - ASU 2016-13	35,137
Commercial loans | Consumer Owner Occupied Loans | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	7,590
Amortized Cost Basis by Origination Year - 2019	3,527
Amortized Cost Basis by Origination Year - 2018	356
Amortized Cost Basis by Origination Year - 2017	339
Amortized Cost Basis by Origination Year - 2016	1,076
Amortized Cost Basis by Origination Year - Prior	1,290
Amortized Cost Basis by Origination Year - Revolving	15,502
Total loans - ASU 2016-13	29,680
Commercial loans | Consumer Owner Occupied Loans | Special mention
Loans
Amortized Cost Basis by Origination Year - 2020	130
Amortized Cost Basis by Origination Year - 2019	3,581
Amortized Cost Basis by Origination Year - 2018	249
Amortized Cost Basis by Origination Year - 2017	62
Amortized Cost Basis by Origination Year - Prior	124
Amortized Cost Basis by Origination Year - Revolving	338
Total loans - ASU 2016-13	4,484
Commercial loans | Consumer Owner Occupied Loans | Substandard
Loans
Amortized Cost Basis by Origination Year - 2020	113
Amortized Cost Basis by Origination Year - 2019	387
Amortized Cost Basis by Origination Year - 2018	142
Amortized Cost Basis by Origination Year - 2016	5
Amortized Cost Basis by Origination Year - Prior	326
Total loans - ASU 2016-13	973
Commercial loans | Other loans
Loans
Amortized Cost Basis by Origination Year - 2020	17,993
Total loans - ASU 2016-13	17,993
Commercial loans | Other loans | Pass
Loans
Amortized Cost Basis by Origination Year - 2020	17,993
Total loans - ASU 2016-13	17,993
Consumer
Loans
Amortized Cost Basis by Origination Year - 2020	1,493,483
Amortized Cost Basis by Origination Year - 2019	1,062,449
Amortized Cost Basis by Origination Year - 2018	737,550
Amortized Cost Basis by Origination Year - 2017	598,194
Amortized Cost Basis by Origination Year - 2016	445,205
Amortized Cost Basis by Origination Year - Prior	1,355,911
Amortized Cost Basis by Origination Year - Revolving	1,313,346
Total loans - ASU 2016-13	7,006,138
Consumer | Current
Loans
Amortized Cost Basis by Origination Year - 2020	1,481,561
Amortized Cost Basis by Origination Year - 2019	1,049,563
Amortized Cost Basis by Origination Year - 2018	731,830
Amortized Cost Basis by Origination Year - 2017	593,491
Amortized Cost Basis by Origination Year - 2016	437,966
Amortized Cost Basis by Origination Year - Prior	1,331,139
Amortized Cost Basis by Origination Year - Revolving	1,308,932
Total loans - ASU 2016-13	6,934,482
Consumer | 30 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	11,344
Amortized Cost Basis by Origination Year - 2019	11,929
Amortized Cost Basis by Origination Year - 2018	3,431
Amortized Cost Basis by Origination Year - 2017	2,685
Amortized Cost Basis by Origination Year - 2016	5,794
Amortized Cost Basis by Origination Year - Prior	12,048
Amortized Cost Basis by Origination Year - Revolving	2,347
Total loans - ASU 2016-13	49,578
Consumer | 60 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	350
Amortized Cost Basis by Origination Year - 2019	493
Amortized Cost Basis by Origination Year - 2018	1,753
Amortized Cost Basis by Origination Year - 2017	682
Amortized Cost Basis by Origination Year - 2016	140
Amortized Cost Basis by Origination Year - Prior	3,573
Amortized Cost Basis by Origination Year - Revolving	465
Total loans - ASU 2016-13	7,456
Consumer | 90 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	228
Amortized Cost Basis by Origination Year - 2019	464
Amortized Cost Basis by Origination Year - 2018	536
Amortized Cost Basis by Origination Year - 2017	1,336
Amortized Cost Basis by Origination Year - 2016	1,305
Amortized Cost Basis by Origination Year - Prior	9,151
Amortized Cost Basis by Origination Year - Revolving	1,602
Total loans - ASU 2016-13	14,622
Consumer | Construction and land development
Loans
Amortized Cost Basis by Origination Year - 2020	377,429
Amortized Cost Basis by Origination Year - 2019	167,920
Amortized Cost Basis by Origination Year - 2018	64,535
Amortized Cost Basis by Origination Year - 2017	18,530
Amortized Cost Basis by Origination Year - 2016	6,752
Amortized Cost Basis by Origination Year - Prior	25,635
Total loans - ASU 2016-13	660,801
Consumer | Construction and land development | Current
Loans
Amortized Cost Basis by Origination Year - 2020	370,975
Amortized Cost Basis by Origination Year - 2019	164,260
Amortized Cost Basis by Origination Year - 2018	63,936
Amortized Cost Basis by Origination Year - 2017	18,530
Amortized Cost Basis by Origination Year - 2016	4,497
Amortized Cost Basis by Origination Year - Prior	25,399
Total loans - ASU 2016-13	647,597
Consumer | Construction and land development | 30 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	6,172
Amortized Cost Basis by Origination Year - 2019	3,660
Amortized Cost Basis by Origination Year - 2018	161
Amortized Cost Basis by Origination Year - 2016	2,255
Amortized Cost Basis by Origination Year - Prior	184
Total loans - ASU 2016-13	12,432
Consumer | Construction and land development | 60 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	282
Amortized Cost Basis by Origination Year - 2018	438
Total loans - ASU 2016-13	720
Consumer | Construction and land development | 90 days past due
Loans
Amortized Cost Basis by Origination Year - Prior	52
Total loans - ASU 2016-13	52
Consumer | Other income producing property
Loans
Amortized Cost Basis by Origination Year - 2020	1,412
Amortized Cost Basis by Origination Year - 2019	1,351
Amortized Cost Basis by Origination Year - 2018	1,310
Amortized Cost Basis by Origination Year - 2017	3,658
Amortized Cost Basis by Origination Year - 2016	2,045
Amortized Cost Basis by Origination Year - Prior	31,633
Total loans - ASU 2016-13	41,409
Consumer | Other income producing property | Current
Loans
Amortized Cost Basis by Origination Year - 2020	1,412
Amortized Cost Basis by Origination Year - 2019	1,351
Amortized Cost Basis by Origination Year - 2018	1,310
Amortized Cost Basis by Origination Year - 2017	3,658
Amortized Cost Basis by Origination Year - 2016	2,045
Amortized Cost Basis by Origination Year - Prior	31,592
Total loans - ASU 2016-13	41,368
Consumer | Other income producing property | 30 days past due
Loans
Amortized Cost Basis by Origination Year - Prior	27
Total loans - ASU 2016-13	27
Consumer | Other income producing property | 60 days past due
Loans
Amortized Cost Basis by Origination Year - Prior	13
Total loans - ASU 2016-13	13
Consumer | Other income producing property | 90 days past due
Loans
Amortized Cost Basis by Origination Year - Prior	1
Total loans - ASU 2016-13	1
Consumer | Consumer Owner Occupied Loans
Loans
Amortized Cost Basis by Origination Year - 2020	815,148
Amortized Cost Basis by Origination Year - 2019	684,198
Amortized Cost Basis by Origination Year - 2018	548,013
Amortized Cost Basis by Origination Year - 2017	512,157
Amortized Cost Basis by Origination Year - 2016	397,242
Amortized Cost Basis by Origination Year - Prior	1,116,147
Total loans - ASU 2016-13	4,072,905
Consumer | Consumer Owner Occupied Loans | Current
Loans
Amortized Cost Basis by Origination Year - 2020	810,215
Amortized Cost Basis by Origination Year - 2019	675,928
Amortized Cost Basis by Origination Year - 2018	543,711
Amortized Cost Basis by Origination Year - 2017	508,160
Amortized Cost Basis by Origination Year - 2016	392,754
Amortized Cost Basis by Origination Year - Prior	1,097,008
Total loans - ASU 2016-13	4,027,776
Consumer | Consumer Owner Occupied Loans | 30 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	4,933
Amortized Cost Basis by Origination Year - 2019	7,744
Amortized Cost Basis by Origination Year - 2018	2,816
Amortized Cost Basis by Origination Year - 2017	2,382
Amortized Cost Basis by Origination Year - 2016	3,510
Amortized Cost Basis by Origination Year - Prior	10,522
Total loans - ASU 2016-13	31,907
Consumer | Consumer Owner Occupied Loans | 60 days past due
Loans
Amortized Cost Basis by Origination Year - 2019	350
Amortized Cost Basis by Origination Year - 2018	1,222
Amortized Cost Basis by Origination Year - 2017	621
Amortized Cost Basis by Origination Year - 2016	103
Amortized Cost Basis by Origination Year - Prior	3,068
Total loans - ASU 2016-13	5,364
Consumer | Consumer Owner Occupied Loans | 90 days past due
Loans
Amortized Cost Basis by Origination Year - 2019	176
Amortized Cost Basis by Origination Year - 2018	264
Amortized Cost Basis by Origination Year - 2017	994
Amortized Cost Basis by Origination Year - 2016	875
Amortized Cost Basis by Origination Year - Prior	5,549
Total loans - ASU 2016-13	7,858
Consumer | Home equity loans
Loans
Amortized Cost Basis by Origination Year - 2020	7,943
Amortized Cost Basis by Origination Year - 2019	6,839
Amortized Cost Basis by Origination Year - 2018	7,670
Amortized Cost Basis by Origination Year - 2017	894
Amortized Cost Basis by Origination Year - 2016	728
Amortized Cost Basis by Origination Year - Prior	32,313
Amortized Cost Basis by Origination Year - Revolving	1,280,302
Total loans - ASU 2016-13	1,336,689
Consumer | Home equity loans | Current
Loans
Amortized Cost Basis by Origination Year - 2020	7,654
Amortized Cost Basis by Origination Year - 2019	6,694
Amortized Cost Basis by Origination Year - 2018	7,670
Amortized Cost Basis by Origination Year - 2017	658
Amortized Cost Basis by Origination Year - 2016	398
Amortized Cost Basis by Origination Year - Prior	30,039
Amortized Cost Basis by Origination Year - Revolving	1,276,058
Total loans - ASU 2016-13	1,329,171
Consumer | Home equity loans | 30 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	134
Amortized Cost Basis by Origination Year - 2019	52
Amortized Cost Basis by Origination Year - 2017	79
Amortized Cost Basis by Origination Year - Prior	272
Amortized Cost Basis by Origination Year - Revolving	2,324
Total loans - ASU 2016-13	2,861
Consumer | Home equity loans | 60 days past due
Loans
Amortized Cost Basis by Origination Year - Prior	116
Amortized Cost Basis by Origination Year - Revolving	418
Total loans - ASU 2016-13	534
Consumer | Home equity loans | 90 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	155
Amortized Cost Basis by Origination Year - 2019	93
Amortized Cost Basis by Origination Year - 2017	157
Amortized Cost Basis by Origination Year - 2016	330
Amortized Cost Basis by Origination Year - Prior	1,886
Amortized Cost Basis by Origination Year - Revolving	1,502
Total loans - ASU 2016-13	4,123
Consumer | Consumer
Loans
Amortized Cost Basis by Origination Year - 2020	291,551
Amortized Cost Basis by Origination Year - 2019	202,141
Amortized Cost Basis by Origination Year - 2018	116,022
Amortized Cost Basis by Origination Year - 2017	62,955
Amortized Cost Basis by Origination Year - 2016	38,438
Amortized Cost Basis by Origination Year - Prior	150,183
Amortized Cost Basis by Origination Year - Revolving	33,044
Total loans - ASU 2016-13	894,334
Consumer | Consumer | Current
Loans
Amortized Cost Basis by Origination Year - 2020	291,305
Amortized Cost Basis by Origination Year - 2019	201,330
Amortized Cost Basis by Origination Year - 2018	115,203
Amortized Cost Basis by Origination Year - 2017	62,485
Amortized Cost Basis by Origination Year - 2016	38,272
Amortized Cost Basis by Origination Year - Prior	147,101
Amortized Cost Basis by Origination Year - Revolving	32,874
Total loans - ASU 2016-13	888,570
Consumer | Consumer | 30 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	105
Amortized Cost Basis by Origination Year - 2019	473
Amortized Cost Basis by Origination Year - 2018	454
Amortized Cost Basis by Origination Year - 2017	224
Amortized Cost Basis by Origination Year - 2016	29
Amortized Cost Basis by Origination Year - Prior	1,043
Amortized Cost Basis by Origination Year - Revolving	23
Total loans - ASU 2016-13	2,351
Consumer | Consumer | 60 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	68
Amortized Cost Basis by Origination Year - 2019	143
Amortized Cost Basis by Origination Year - 2018	93
Amortized Cost Basis by Origination Year - 2017	61
Amortized Cost Basis by Origination Year - 2016	37
Amortized Cost Basis by Origination Year - Prior	376
Amortized Cost Basis by Origination Year - Revolving	47
Total loans - ASU 2016-13	825
Consumer | Consumer | 90 days past due
Loans
Amortized Cost Basis by Origination Year - 2020	73
Amortized Cost Basis by Origination Year - 2019	195
Amortized Cost Basis by Origination Year - 2018	272
Amortized Cost Basis by Origination Year - 2017	185
Amortized Cost Basis by Origination Year - 2016	100
Amortized Cost Basis by Origination Year - Prior	1,663
Amortized Cost Basis by Origination Year - Revolving	100
Total loans - ASU 2016-13	$ 2,588

Loans - Credit risk profile b_2

Loans - Credit risk profile by risk grade of non acquired loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans
Total loans	$ 24,664,134	$ 11,375,104
Total loans - ASU 2016-13	24,664,134
Other Real Estate, Non Covered	47,920	11,964	$ 11,410	$ 11,203
Construction and land development
Loans
Total loans - ASU 2016-13	1,899,066
Commercial non-owner occupied
Loans
Total loans - ASU 2016-13	5,931,323
Commercial owner occupied real estate loan
Loans
Total loans - ASU 2016-13	4,842,092
Commercial and industrial
Loans
Total loans - ASU 2016-13	5,047,147
Other income producing property
Loans
Total loans - ASU 2016-13	587,448
Consumer Owner Occupied Loans
Loans
Total loans - ASU 2016-13	4,108,042
Home equity loans
Loans
Total loans - ASU 2016-13	1,336,689
Consumer
Loans
Total loans - ASU 2016-13	894,334
Other loans
Loans
Total loans - ASU 2016-13	17,993
Commercial loans
Loans
Total loans - ASU 2016-13	17,657,996
Commercial loans | Pass
Loans
Total loans - ASU 2016-13	16,665,456
Commercial loans | Special mention
Loans
Total loans - ASU 2016-13	671,626
Commercial loans | Substandard
Loans
Total loans - ASU 2016-13	320,880
Commercial loans | Doubtful
Loans
Total loans - ASU 2016-13	34
Commercial loans | Construction and land development
Loans
Total loans	1,899,066	1,017,261
Total loans - ASU 2016-13	1,238,265
Commercial loans | Construction and land development | Pass
Loans
Total loans - ASU 2016-13	1,190,196
Commercial loans | Construction and land development | Special mention
Loans
Total loans - ASU 2016-13	38,152
Commercial loans | Construction and land development | Substandard
Loans
Total loans - ASU 2016-13	9,909
Commercial loans | Construction and land development | Doubtful
Loans
Total loans - ASU 2016-13	8
Commercial loans | Commercial non-owner occupied
Loans
Total loans	5,931,323	2,323,967
Total loans - ASU 2016-13	5,931,323
Commercial loans | Commercial non-owner occupied | Pass
Loans
Total loans - ASU 2016-13	5,318,569
Commercial loans | Commercial non-owner occupied | Special mention
Loans
Total loans - ASU 2016-13	445,290
Commercial loans | Commercial non-owner occupied | Substandard
Loans
Total loans - ASU 2016-13	167,460
Commercial loans | Commercial non-owner occupied | Doubtful
Loans
Total loans - ASU 2016-13	4
Commercial loans | Commercial owner occupied real estate loan
Loans
Total loans - ASU 2016-13	4,842,092
Commercial loans | Commercial owner occupied real estate loan | Pass
Loans
Total loans - ASU 2016-13	4,631,256
Commercial loans | Commercial owner occupied real estate loan | Special mention
Loans
Total loans - ASU 2016-13	112,848
Commercial loans | Commercial owner occupied real estate loan | Substandard
Loans
Total loans - ASU 2016-13	97,982
Commercial loans | Commercial owner occupied real estate loan | Doubtful
Loans
Total loans - ASU 2016-13	6
Commercial loans | Commercial and industrial
Loans
Total loans	5,047,147	1,386,327
Total loans - ASU 2016-13	5,047,147
Commercial loans | Commercial and industrial | Pass
Loans
Total loans - ASU 2016-13	4,968,038
Commercial loans | Commercial and industrial | Special mention
Loans
Total loans - ASU 2016-13	52,704
Commercial loans | Commercial and industrial | Substandard
Loans
Total loans - ASU 2016-13	26,395
Commercial loans | Commercial and industrial | Doubtful
Loans
Total loans - ASU 2016-13	10
Commercial loans | Other income producing property
Loans
Total loans	587,448	346,554
Total loans - ASU 2016-13	546,039
Commercial loans | Other income producing property | Pass
Loans
Total loans - ASU 2016-13	509,724
Commercial loans | Other income producing property | Special mention
Loans
Total loans - ASU 2016-13	18,148
Commercial loans | Other income producing property | Substandard
Loans
Total loans - ASU 2016-13	18,161
Commercial loans | Other income producing property | Doubtful
Loans
Total loans - ASU 2016-13	6
Commercial loans | Consumer Owner Occupied Loans
Loans
Total loans - ASU 2016-13	35,137
Commercial loans | Consumer Owner Occupied Loans | Pass
Loans
Total loans - ASU 2016-13	29,680
Commercial loans | Consumer Owner Occupied Loans | Special mention
Loans
Total loans - ASU 2016-13	4,484
Commercial loans | Consumer Owner Occupied Loans | Substandard
Loans
Total loans - ASU 2016-13	973
Commercial loans | Other loans
Loans
Total loans - ASU 2016-13	17,993
Commercial loans | Other loans | Pass
Loans
Total loans - ASU 2016-13	17,993
Consumer
Loans
Total loans - ASU 2016-13	7,006,138
Consumer | Construction and land development
Loans
Total loans - ASU 2016-13	660,801
Consumer | Other income producing property
Loans
Total loans - ASU 2016-13	41,409
Consumer | Consumer Owner Occupied Loans
Loans
Total loans	4,108,042	2,706,960
Total loans - ASU 2016-13	4,072,905
Consumer | Home equity loans
Loans
Total loans	1,336,689	758,020
Total loans - ASU 2016-13	1,336,689
Consumer | Consumer
Loans
Total loans	894,334	663,422
Total loans - ASU 2016-13	894,334
Consumer | Other loans
Loans
Total loans	17,993	13,892
Non-acquired loans
Loans
Total loans		9,252,831	7,933,286
Total loans - ASU 2016-13	$ 12,289,456	9,252,831
Non-acquired loans | Pass
Loans
Total loans		9,123,097
Non-acquired loans | Special mention
Loans
Total loans		83,830
Non-acquired loans | Substandard
Loans
Total loans		45,904
Non-acquired loans | Construction and land development
Loans
Total loans		968,360	841,445
Non-acquired loans | Commercial non-owner occupied
Loans
Total loans		1,811,138	1,415,551
Non-acquired loans | Commercial owner occupied real estate loan
Loans
Total loans		1,784,017	1,517,551
Non-acquired loans | Commercial and industrial
Loans
Total loans		1,280,859	1,054,952
Non-acquired loans | Other income producing property
Loans
Total loans		218,617	214,353
Total loans - ASU 2016-13		218,617
Non-acquired loans | Consumer Owner Occupied Loans
Loans
Total loans		2,118,839	1,936,265
Non-acquired loans | Home equity loans
Loans
Total loans		518,628	495,148
Non-acquired loans | Consumer
Loans
Total loans		538,481	448,664
Non-acquired loans | Other loans
Loans
Total loans		13,892	$ 9,357
Non-acquired loans | Commercial loans
Loans
Total loans		6,062,991
Total loans - ASU 2016-13		1,280,859
Non-acquired loans | Commercial loans | Pass
Loans
Total loans		5,971,069
Non-acquired loans | Commercial loans | Special mention
Loans
Total loans		69,268
Non-acquired loans | Commercial loans | Substandard
Loans
Total loans		22,654
Non-acquired loans | Commercial loans | Construction and land development
Loans
Total loans		968,360
Total loans - ASU 2016-13		968,360
Non-acquired loans | Commercial loans | Construction and land development | Pass
Loans
Total loans		959,206
Non-acquired loans | Commercial loans | Construction and land development | Special mention
Loans
Total loans		7,095
Non-acquired loans | Commercial loans | Construction and land development | Substandard
Loans
Total loans		2,059
Non-acquired loans | Commercial loans | Commercial non-owner occupied
Loans
Total loans		1,811,138
Total loans - ASU 2016-13		1,811,138
Non-acquired loans | Commercial loans | Commercial non-owner occupied | Pass
Loans
Total loans		1,787,306
Non-acquired loans | Commercial loans | Commercial non-owner occupied | Special mention
Loans
Total loans		22,410
Non-acquired loans | Commercial loans | Commercial non-owner occupied | Substandard
Loans
Total loans		1,422
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan
Loans
Total loans		1,784,017
Total loans - ASU 2016-13		1,784,017
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan | Pass
Loans
Total loans		1,754,801
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan | Special mention
Loans
Total loans		19,742
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan | Substandard
Loans
Total loans		9,474
Non-acquired loans | Commercial loans | Commercial and industrial
Loans
Total loans		1,280,859
Non-acquired loans | Commercial loans | Commercial and industrial | Pass
Loans
Total loans		1,256,465
Non-acquired loans | Commercial loans | Commercial and industrial | Special mention
Loans
Total loans		16,055
Non-acquired loans | Commercial loans | Commercial and industrial | Substandard
Loans
Total loans		8,339
Non-acquired loans | Commercial loans | Other income producing property
Loans
Total loans		218,617
Non-acquired loans | Commercial loans | Other income producing property | Pass
Loans
Total loans		213,291
Non-acquired loans | Commercial loans | Other income producing property | Special mention
Loans
Total loans		3,966
Non-acquired loans | Commercial loans | Other income producing property | Substandard
Loans
Total loans		1,360
Non-acquired loans | Consumer
Loans
Total loans		3,189,840
Non-acquired loans | Consumer | Pass
Loans
Total loans		3,152,028
Non-acquired loans | Consumer | Special mention
Loans
Total loans		14,562
Non-acquired loans | Consumer | Substandard
Loans
Total loans		23,250
Non-acquired loans | Consumer | Consumer Owner Occupied Loans
Loans
Total loans		2,118,839
Total loans - ASU 2016-13		2,118,839
Non-acquired loans | Consumer | Consumer Owner Occupied Loans | Pass
Loans
Total loans		2,094,080
Non-acquired loans | Consumer | Consumer Owner Occupied Loans | Special mention
Loans
Total loans		9,585
Non-acquired loans | Consumer | Consumer Owner Occupied Loans | Substandard
Loans
Total loans		15,174
Non-acquired loans | Consumer | Home equity loans
Loans
Total loans		518,628
Total loans - ASU 2016-13		518,628
Non-acquired loans | Consumer | Home equity loans | Pass
Loans
Total loans		508,054
Non-acquired loans | Consumer | Home equity loans | Special mention
Loans
Total loans		4,490
Non-acquired loans | Consumer | Home equity loans | Substandard
Loans
Total loans		6,084
Non-acquired loans | Consumer | Consumer
Loans
Total loans		538,481
Total loans - ASU 2016-13		538,481
Non-acquired loans | Consumer | Consumer | Pass
Loans
Total loans		536,002
Non-acquired loans | Consumer | Consumer | Special mention
Loans
Total loans		487
Non-acquired loans | Consumer | Consumer | Substandard
Loans
Total loans		1,992
Non-acquired loans | Consumer | Other loans
Loans
Total loans		13,892
Total loans - ASU 2016-13		13,892
Non-acquired loans | Consumer | Other loans | Pass
Loans
Total loans		$ 13,892

Loans - Credit risk profile b_3

Loans - Credit risk profile by risk grade of acquired non-credit impaired loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans
Total loans	$ 24,664,134	$ 11,375,104
Commercial loans | Construction and land development
Loans
Total loans	1,899,066	1,017,261
Commercial loans | Commercial non-owner occupied
Loans
Total loans	5,931,323	2,323,967
Commercial loans | Commercial and industrial
Loans
Total loans	5,047,147	1,386,327
Commercial loans | Other income producing property
Loans
Total loans	587,448	346,554
Consumer | Consumer Owner Occupied Loans
Loans
Total loans	4,108,042	2,706,960
Consumer | Home equity loans
Loans
Total loans	1,336,689	758,020
Consumer | Consumer
Loans
Total loans	894,334	663,422
Consumer | Other loans
Loans
Total loans	$ 17,993	13,892
Acquired non-credit impaired loans
Loans
Total loans		1,760,427	$ 2,594,826
Acquired non-credit impaired loans | Pass
Loans
Total loans		1,697,942
Acquired non-credit impaired loans | Special mention
Loans
Total loans		39,772
Acquired non-credit impaired loans | Substandard
Loans
Total loans		22,713
Acquired non-credit impaired loans | Construction and land development
Loans
Total loans		33,569	165,070
Acquired non-credit impaired loans | Commercial non-owner occupied
Loans
Total loans		447,441	679,253
Acquired non-credit impaired loans | Commercial owner occupied real estate loan
Loans
Total loans		307,193	421,841
Acquired non-credit impaired loans | Commercial and industrial
Loans
Total loans		101,880	212,537
Acquired non-credit impaired loans | Other income producing property
Loans
Total loans		95,697	133,110
Acquired non-credit impaired loans | Consumer Owner Occupied Loans
Loans
Total loans		496,431	628,813
Acquired non-credit impaired loans | Home equity loans
Loans
Total loans		188,732	242,425
Acquired non-credit impaired loans | Consumer
Loans
Total loans		89,484	$ 111,777
Acquired non-credit impaired loans | Commercial loans
Loans
Total loans		985,780
Acquired non-credit impaired loans | Commercial loans | Pass
Loans
Total loans		950,062
Acquired non-credit impaired loans | Commercial loans | Special mention
Loans
Total loans		27,005
Acquired non-credit impaired loans | Commercial loans | Substandard
Loans
Total loans		8,713
Acquired non-credit impaired loans | Commercial loans | Construction and land development
Loans
Total loans		33,569
Acquired non-credit impaired loans | Commercial loans | Construction and land development | Pass
Loans
Total loans		31,690
Acquired non-credit impaired loans | Commercial loans | Construction and land development | Special mention
Loans
Total loans		966
Acquired non-credit impaired loans | Commercial loans | Construction and land development | Substandard
Loans
Total loans		913
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied
Loans
Total loans		447,441
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied | Pass
Loans
Total loans		432,710
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied | Special mention
Loans
Total loans		14,162
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied | Substandard
Loans
Total loans		569
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan
Loans
Total loans		307,193
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan | Pass
Loans
Total loans		300,678
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan | Special mention
Loans
Total loans		3,092
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan | Substandard
Loans
Total loans		3,423
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial
Loans
Total loans		101,880
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial | Pass
Loans
Total loans		97,092
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial | Special mention
Loans
Total loans		2,948
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial | Substandard
Loans
Total loans		1,840
Acquired non-credit impaired loans | Commercial loans | Other income producing property
Loans
Total loans		95,697
Acquired non-credit impaired loans | Commercial loans | Other income producing property | Pass
Loans
Total loans		87,892
Acquired non-credit impaired loans | Commercial loans | Other income producing property | Special mention
Loans
Total loans		5,837
Acquired non-credit impaired loans | Commercial loans | Other income producing property | Substandard
Loans
Total loans		1,968
Acquired non-credit impaired loans | Consumer
Loans
Total loans		774,647
Acquired non-credit impaired loans | Consumer | Pass
Loans
Total loans		747,880
Acquired non-credit impaired loans | Consumer | Special mention
Loans
Total loans		12,767
Acquired non-credit impaired loans | Consumer | Substandard
Loans
Total loans		14,000
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans
Loans
Total loans		496,431
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans | Pass
Loans
Total loans		486,433
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans | Special mention
Loans
Total loans		6,434
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans | Substandard
Loans
Total loans		3,564
Acquired non-credit impaired loans | Consumer | Home equity loans
Loans
Total loans		188,732
Acquired non-credit impaired loans | Consumer | Home equity loans | Pass
Loans
Total loans		174,912
Acquired non-credit impaired loans | Consumer | Home equity loans | Special mention
Loans
Total loans		5,679
Acquired non-credit impaired loans | Consumer | Home equity loans | Substandard
Loans
Total loans		8,141
Acquired non-credit impaired loans | Consumer | Consumer
Loans
Total loans		89,484
Acquired non-credit impaired loans | Consumer | Consumer | Pass
Loans
Total loans		86,535
Acquired non-credit impaired loans | Consumer | Consumer | Special mention
Loans
Total loans		654
Acquired non-credit impaired loans | Consumer | Consumer | Substandard
Loans
Total loans		$ 2,295

Loans - Credit risk profile b_4

Loans - Credit risk profile by risk grade of acquired credit impaired loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans
Total loans	$ 24,664,134	$ 11,375,104
Commercial loans | Construction and land development
Loans
Total loans	1,899,066	1,017,261
Commercial loans | Commercial and industrial
Loans
Total loans	5,047,147	1,386,327
Consumer | Consumer
Loans
Total loans	$ 894,334	663,422
Acquired credit impaired loans
Loans
Total loans		361,846	$ 489,723
Acquired credit impaired loans | Pass
Loans
Total loans		218,364
Acquired credit impaired loans | Special mention
Loans
Total loans		58,281
Acquired credit impaired loans | Substandard
Loans
Total loans		85,201
Acquired credit impaired loans | Construction and land development
Loans
Total loans		25,032	32,942
Acquired credit impaired loans | Consumer
Loans
Total loans		35,488	42,492
Acquired credit impaired loans | Commercial and industrial
Loans
Total loans		7,029	10,043
Acquired credit impaired loans | Commercial loans | Real estate
Loans
Total loans		130,938	196,764
Acquired credit impaired loans | Commercial loans | Real estate | Pass
Loans
Total loans		108,762
Acquired credit impaired loans | Commercial loans | Real estate | Special mention
Loans
Total loans		6,465
Acquired credit impaired loans | Commercial loans | Real estate | Substandard
Loans
Total loans		15,711
Acquired credit impaired loans | Commercial loans | Construction and land development
Loans
Total loans		25,032
Acquired credit impaired loans | Commercial loans | Construction and land development | Pass
Loans
Total loans		17,756
Acquired credit impaired loans | Commercial loans | Construction and land development | Special mention
Loans
Total loans		2,904
Acquired credit impaired loans | Commercial loans | Construction and land development | Substandard
Loans
Total loans		4,372
Acquired credit impaired loans | Commercial loans | Commercial and industrial
Loans
Total loans		7,029
Acquired credit impaired loans | Consumer | Real estate
Loans
Total loans		163,359	$ 207,482
Acquired credit impaired loans | Consumer | Real estate | Pass
Loans
Total loans		82,203
Acquired credit impaired loans | Consumer | Real estate | Special mention
Loans
Total loans		35,968
Acquired credit impaired loans | Consumer | Real estate | Substandard
Loans
Total loans		45,188
Acquired credit impaired loans | Consumer | Consumer
Loans
Total loans		35,488
Acquired credit impaired loans | Consumer | Consumer | Pass
Loans
Total loans		4,483
Acquired credit impaired loans | Consumer | Consumer | Special mention
Loans
Total loans		12,658
Acquired credit impaired loans | Consumer | Consumer | Substandard
Loans
Total loans		18,347
Acquired credit impaired loans | Consumer | Commercial and industrial
Loans
Total loans		7,029
Acquired credit impaired loans | Consumer | Commercial and industrial | Pass
Loans
Total loans		5,160
Acquired credit impaired loans | Consumer | Commercial and industrial | Special mention
Loans
Total loans		286
Acquired credit impaired loans | Consumer | Commercial and industrial | Substandard
Loans
Total loans		$ 1,583

Loans - Aging analysis of past

Loans - Aging analysis of past due loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans and Allowance for Loan Losses
Past due	$ 61,216
Current	24,507,730
Non-Accruing	95,188
Total loans - ASU 2016-13	24,664,134
Greater than 90 Days Accruing	11,651
30 days past due
Loans and Allowance for Loan Losses
Past due	20,185
60 days past due
Loans and Allowance for Loan Losses
Past due	29,380
90 days past due
Loans and Allowance for Loan Losses
Past due	11,651
Non-acquired loans
Loans and Allowance for Loan Losses
Past due		$ 22,696
Current		9,230,135
Total loans - ASU 2016-13	12,289,456	9,252,831
Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		13,535
Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		1,387
Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		7,774
Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		13,916
Current		1,746,511
Total loans - ASU 2016-13		1,760,427
Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		3,147
Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		7,180
Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		3,589
Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		17,460
Current		344,386
Total loans - ASU 2016-13		361,846
Acquired credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		6,059
Acquired credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		2,169
Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		9,232
Construction and land development
Loans and Allowance for Loan Losses
Past due	1,662
Current	1,894,983
Non-Accruing	2,421
Total loans - ASU 2016-13	1,899,066
Construction and land development | 30 days past due
Loans and Allowance for Loan Losses
Past due	520
Construction and land development | 60 days past due
Loans and Allowance for Loan Losses
Past due	1,142
Commercial non-owner occupied
Loans and Allowance for Loan Losses
Past due	1,031
Current	5,925,696
Non-Accruing	4,596
Total loans - ASU 2016-13	5,931,323
Commercial non-owner occupied | 30 days past due
Loans and Allowance for Loan Losses
Past due	188
Commercial non-owner occupied | 60 days past due
Loans and Allowance for Loan Losses
Past due	372
Commercial non-owner occupied | 90 days past due
Loans and Allowance for Loan Losses
Past due	471
Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Past due	3,740
Current	4,812,293
Non-Accruing	26,059
Total loans - ASU 2016-13	4,842,092
Commercial owner occupied real estate loan | 30 days past due
Loans and Allowance for Loan Losses
Past due	2,900
Commercial owner occupied real estate loan | 60 days past due
Loans and Allowance for Loan Losses
Past due	840
Residential real estate | Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		9,385
Current		153,974
Total loans - ASU 2016-13		163,359
Residential real estate | Acquired credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		2,838
Residential real estate | Acquired credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		976
Residential real estate | Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		5,571
Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Past due	5,041
Current	4,072,255
Non-Accruing	30,746
Total loans - ASU 2016-13	4,108,042
Consumer Owner Occupied Loans | 30 days past due
Loans and Allowance for Loan Losses
Past due	1,375
Consumer Owner Occupied Loans | 60 days past due
Loans and Allowance for Loan Losses
Past due	3,632
Consumer Owner Occupied Loans | 90 days past due
Loans and Allowance for Loan Losses
Past due	34
Home equity loans
Loans and Allowance for Loan Losses
Past due	2,286
Current	1,324,459
Non-Accruing	9,944
Total loans - ASU 2016-13	1,336,689
Home equity loans | 30 days past due
Loans and Allowance for Loan Losses
Past due	1,805
Home equity loans | 60 days past due
Loans and Allowance for Loan Losses
Past due	481
Commercial and industrial
Loans and Allowance for Loan Losses
Past due	43,932
Current	4,993,997
Non-Accruing	9,218
Total loans - ASU 2016-13	5,047,147
Commercial and industrial | 30 days past due
Loans and Allowance for Loan Losses
Past due	10,979
Commercial and industrial | 60 days past due
Loans and Allowance for Loan Losses
Past due	22,089
Commercial and industrial | 90 days past due
Loans and Allowance for Loan Losses
Past due	10,864
Other income producing property
Loans and Allowance for Loan Losses
Past due	965
Current	580,353
Non-Accruing	6,130
Total loans - ASU 2016-13	587,448
Other income producing property | 30 days past due
Loans and Allowance for Loan Losses
Past due	687
Other income producing property | 90 days past due
Loans and Allowance for Loan Losses
Past due	278
Other income producing property | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		665
Current		217,952
Total loans - ASU 2016-13		218,617
Other income producing property | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		208
Other income producing property | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		457
Other income producing property | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		5,238
Current		90,459
Total loans - ASU 2016-13		95,697
Other income producing property | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		378
Other income producing property | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		4,309
Other income producing property | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		551
Consumer
Loans and Allowance for Loan Losses
Past due	2,540
Current	885,720
Non-Accruing	6,074
Total loans - ASU 2016-13	894,334
Consumer | 30 days past due
Loans and Allowance for Loan Losses
Past due	1,718
Consumer | 60 days past due
Loans and Allowance for Loan Losses
Past due	818
Consumer | 90 days past due
Loans and Allowance for Loan Losses
Past due	4
Other loans
Loans and Allowance for Loan Losses
Past due	19
Current	17,974
Total loans - ASU 2016-13	17,993
Other loans | 30 days past due
Loans and Allowance for Loan Losses
Past due	13
Other loans | 60 days past due
Loans and Allowance for Loan Losses
Past due	6
Commercial loans
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	17,657,996
Commercial loans | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		6,280
Current		1,274,579
Total loans - ASU 2016-13		1,280,859
Commercial loans | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		5,531
Commercial loans | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		100
Commercial loans | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		649
Commercial loans | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		2,290
Current		304,903
Total loans - ASU 2016-13		307,193
Commercial loans | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		890
Commercial loans | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		702
Commercial loans | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		698
Commercial loans | Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		1,103
Current		5,926
Total loans - ASU 2016-13		7,029
Commercial loans | Acquired credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		118
Commercial loans | Acquired credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		910
Commercial loans | Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		75
Commercial loans | Construction and land development
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	1,238,265
Commercial loans | Construction and land development | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		615
Current		967,745
Total loans - ASU 2016-13		968,360
Commercial loans | Construction and land development | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		321
Commercial loans | Construction and land development | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		39
Commercial loans | Construction and land development | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		255
Commercial loans | Construction and land development | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		276
Current		33,293
Total loans - ASU 2016-13		33,569
Commercial loans | Construction and land development | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		20
Commercial loans | Construction and land development | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		256
Commercial loans | Construction and land development | Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		393
Current		24,639
Total loans - ASU 2016-13		25,032
Commercial loans | Construction and land development | Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		393
Commercial loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	5,931,323
Greater than 90 Days Accruing	471
Commercial loans | Commercial non-owner occupied | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		413
Current		1,810,725
Total loans - ASU 2016-13		1,811,138
Commercial loans | Commercial non-owner occupied | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		114
Commercial loans | Commercial non-owner occupied | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		299
Commercial loans | Commercial non-owner occupied | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		1,366
Current		446,075
Total loans - ASU 2016-13		447,441
Commercial loans | Commercial non-owner occupied | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		144
Commercial loans | Commercial non-owner occupied | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		1,146
Commercial loans | Commercial non-owner occupied | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		76
Commercial loans | Commercial non-owner occupied | Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		4,942
Current		125,996
Total loans - ASU 2016-13		130,938
Commercial loans | Commercial non-owner occupied | Acquired credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		2,283
Commercial loans | Commercial non-owner occupied | Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		2,659
Commercial loans | Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	4,842,092
Commercial loans | Commercial owner occupied real estate loan | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		6,949
Current		1,777,068
Total loans - ASU 2016-13		1,784,017
Commercial loans | Commercial owner occupied real estate loan | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		4,011
Commercial loans | Commercial owner occupied real estate loan | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		636
Commercial loans | Commercial owner occupied real estate loan | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		2,302
Commercial loans | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	35,137
Commercial loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	5,047,147
Greater than 90 Days Accruing	10,864
Commercial loans | Commercial and industrial | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		314
Current		101,566
Total loans - ASU 2016-13		101,880
Commercial loans | Commercial and industrial | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		93
Commercial loans | Commercial and industrial | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		204
Commercial loans | Commercial and industrial | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		17
Commercial loans | Other income producing property
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	546,039
Greater than 90 Days Accruing	278
Commercial loans | Other loans
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	17,993
Consumer
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	7,006,138
Consumer | 30 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	49,578
Consumer | 60 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	7,456
Consumer | 90 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	14,622
Consumer | Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		1,637
Current		33,851
Total loans - ASU 2016-13		35,488
Consumer | Acquired credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		820
Consumer | Acquired credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		283
Consumer | Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		534
Consumer | Construction and land development
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	660,801
Consumer | Construction and land development | 30 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	12,432
Consumer | Construction and land development | 60 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	720
Consumer | Construction and land development | 90 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	52
Consumer | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	4,072,905
Greater than 90 Days Accruing	34
Consumer | Consumer Owner Occupied Loans | 30 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	31,907
Consumer | Consumer Owner Occupied Loans | 60 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	5,364
Consumer | Consumer Owner Occupied Loans | 90 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	7,858
Consumer | Consumer Owner Occupied Loans | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		3,866
Current		2,114,973
Total loans - ASU 2016-13		2,118,839
Consumer | Consumer Owner Occupied Loans | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		1,157
Consumer | Consumer Owner Occupied Loans | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		285
Consumer | Consumer Owner Occupied Loans | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		2,424
Consumer | Consumer Owner Occupied Loans | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		1,333
Current		495,098
Total loans - ASU 2016-13		496,431
Consumer | Consumer Owner Occupied Loans | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		768
Consumer | Consumer Owner Occupied Loans | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		151
Consumer | Consumer Owner Occupied Loans | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		414
Consumer | Home equity loans
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	1,336,689
Consumer | Home equity loans | 30 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	2,861
Consumer | Home equity loans | 60 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	534
Consumer | Home equity loans | 90 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	4,123
Consumer | Home equity loans | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		1,944
Current		516,684
Total loans - ASU 2016-13		518,628
Consumer | Home equity loans | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		1,343
Consumer | Home equity loans | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		39
Consumer | Home equity loans | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		562
Consumer | Home equity loans | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		1,578
Current		187,154
Total loans - ASU 2016-13		188,732
Consumer | Home equity loans | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		369
Consumer | Home equity loans | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		55
Consumer | Home equity loans | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		1,154
Consumer | Other income producing property
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	41,409
Consumer | Other income producing property | 30 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	27
Consumer | Other income producing property | 60 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	13
Consumer | Other income producing property | 90 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	1
Consumer | Consumer
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	894,334
Greater than 90 Days Accruing	4
Consumer | Consumer | 30 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	2,351
Consumer | Consumer | 60 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	825
Consumer | Consumer | 90 days past due
Loans and Allowance for Loan Losses
Total loans - ASU 2016-13	$ 2,588
Consumer | Consumer | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		1,936
Current		536,545
Total loans - ASU 2016-13		538,481
Consumer | Consumer | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		825
Consumer | Consumer | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		285
Consumer | Consumer | Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		826
Consumer | Consumer | Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		1,521
Current		87,963
Total loans - ASU 2016-13		89,484
Consumer | Consumer | Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		485
Consumer | Consumer | Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		613
Consumer | Consumer | Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		423
Consumer | Other loans | Non-acquired loans
Loans and Allowance for Loan Losses
Past due		28
Current		13,864
Total loans - ASU 2016-13		13,892
Consumer | Other loans | Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		25
Consumer | Other loans | Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		$ 3

Loans - Aging analysis of pas_2

Loans - Aging analysis of past due loans Prior to adoption of ASU 2016-13 (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans and Allowance for Loan Losses
Past due	$ 61,216
Current	24,507,730
Non-Accruing	95,188
Total loans	24,664,134	$ 11,375,104
30 days past due
Loans and Allowance for Loan Losses
Past due	20,185
60 days past due
Loans and Allowance for Loan Losses
Past due	29,380
90 days past due
Loans and Allowance for Loan Losses
Past due	11,651
Construction and land development
Loans and Allowance for Loan Losses
Past due	1,662
Current	1,894,983
Non-Accruing	2,421
Construction and land development | 30 days past due
Loans and Allowance for Loan Losses
Past due	520
Construction and land development | 60 days past due
Loans and Allowance for Loan Losses
Past due	1,142
Commercial non-owner occupied
Loans and Allowance for Loan Losses
Past due	1,031
Current	5,925,696
Non-Accruing	4,596
Commercial non-owner occupied | 30 days past due
Loans and Allowance for Loan Losses
Past due	188
Commercial non-owner occupied | 60 days past due
Loans and Allowance for Loan Losses
Past due	372
Commercial non-owner occupied | 90 days past due
Loans and Allowance for Loan Losses
Past due	471
Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Past due	3,740
Current	4,812,293
Non-Accruing	26,059
Commercial owner occupied real estate loan | 30 days past due
Loans and Allowance for Loan Losses
Past due	2,900
Commercial owner occupied real estate loan | 60 days past due
Loans and Allowance for Loan Losses
Past due	840
Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Past due	5,041
Current	4,072,255
Non-Accruing	30,746
Consumer Owner Occupied Loans | 30 days past due
Loans and Allowance for Loan Losses
Past due	1,375
Consumer Owner Occupied Loans | 60 days past due
Loans and Allowance for Loan Losses
Past due	3,632
Consumer Owner Occupied Loans | 90 days past due
Loans and Allowance for Loan Losses
Past due	34
Home equity loans
Loans and Allowance for Loan Losses
Past due	2,286
Current	1,324,459
Non-Accruing	9,944
Home equity loans | 30 days past due
Loans and Allowance for Loan Losses
Past due	1,805
Home equity loans | 60 days past due
Loans and Allowance for Loan Losses
Past due	481
Commercial and industrial
Loans and Allowance for Loan Losses
Past due	43,932
Current	4,993,997
Non-Accruing	9,218
Commercial and industrial | 30 days past due
Loans and Allowance for Loan Losses
Past due	10,979
Commercial and industrial | 60 days past due
Loans and Allowance for Loan Losses
Past due	22,089
Commercial and industrial | 90 days past due
Loans and Allowance for Loan Losses
Past due	10,864
Other income producing property
Loans and Allowance for Loan Losses
Past due	965
Current	580,353
Non-Accruing	6,130
Other income producing property | 30 days past due
Loans and Allowance for Loan Losses
Past due	687
Other income producing property | 90 days past due
Loans and Allowance for Loan Losses
Past due	278
Consumer
Loans and Allowance for Loan Losses
Past due	2,540
Current	885,720
Non-Accruing	6,074
Consumer | 30 days past due
Loans and Allowance for Loan Losses
Past due	1,718
Consumer | 60 days past due
Loans and Allowance for Loan Losses
Past due	818
Consumer | 90 days past due
Loans and Allowance for Loan Losses
Past due	4
Other loans
Loans and Allowance for Loan Losses
Past due	19
Current	17,974
Other loans | 30 days past due
Loans and Allowance for Loan Losses
Past due	13
Other loans | 60 days past due
Loans and Allowance for Loan Losses
Past due	6
Commercial loans | Construction and land development
Loans and Allowance for Loan Losses
Total loans	1,899,066	1,017,261
Commercial loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Total loans	5,931,323	2,323,967
Commercial loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans	5,047,147	1,386,327
Commercial loans | Other income producing property
Loans and Allowance for Loan Losses
Total loans	587,448	346,554
Consumer | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Total loans	4,108,042	2,706,960
Consumer | Home equity loans
Loans and Allowance for Loan Losses
Total loans	1,336,689	758,020
Consumer | Consumer
Loans and Allowance for Loan Losses
Total loans	894,334	663,422
Consumer | Other loans
Loans and Allowance for Loan Losses
Total loans	$ 17,993	13,892
Non-acquired loans
Loans and Allowance for Loan Losses
Past due		22,696
Current		9,230,135
Total loans		9,252,831	$ 7,933,286
Non-acquired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		13,535
Non-acquired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		1,387
Non-acquired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		7,774
Non-acquired loans | Construction and land development
Loans and Allowance for Loan Losses
Total loans		968,360	841,445
Non-acquired loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Total loans		1,811,138	1,415,551
Non-acquired loans | Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Total loans		1,784,017	1,517,551
Non-acquired loans | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Total loans		2,118,839	1,936,265
Non-acquired loans | Home equity loans
Loans and Allowance for Loan Losses
Total loans		518,628	495,148
Non-acquired loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans		1,280,859	1,054,952
Non-acquired loans | Other income producing property
Loans and Allowance for Loan Losses
Past due		665
Current		217,952
Total loans		218,617	214,353
Non-acquired loans | Other income producing property | 30 days past due
Loans and Allowance for Loan Losses
Past due		208
Non-acquired loans | Other income producing property | 90 days past due
Loans and Allowance for Loan Losses
Past due		457
Non-acquired loans | Consumer
Loans and Allowance for Loan Losses
Total loans		538,481	448,664
Non-acquired loans | Other loans
Loans and Allowance for Loan Losses
Total loans		13,892	9,357
Non-acquired loans | Commercial loans
Loans and Allowance for Loan Losses
Past due		6,280
Current		1,274,579
Total loans		6,062,991
Non-acquired loans | Commercial loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		5,531
Non-acquired loans | Commercial loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		100
Non-acquired loans | Commercial loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		649
Non-acquired loans | Commercial loans | Construction and land development
Loans and Allowance for Loan Losses
Past due		615
Current		967,745
Total loans		968,360
Non-acquired loans | Commercial loans | Construction and land development | 30 days past due
Loans and Allowance for Loan Losses
Past due		321
Non-acquired loans | Commercial loans | Construction and land development | 60 days past due
Loans and Allowance for Loan Losses
Past due		39
Non-acquired loans | Commercial loans | Construction and land development | 90 days past due
Loans and Allowance for Loan Losses
Past due		255
Non-acquired loans | Commercial loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Past due		413
Current		1,810,725
Total loans		1,811,138
Non-acquired loans | Commercial loans | Commercial non-owner occupied | 30 days past due
Loans and Allowance for Loan Losses
Past due		114
Non-acquired loans | Commercial loans | Commercial non-owner occupied | 90 days past due
Loans and Allowance for Loan Losses
Past due		299
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Past due		6,949
Current		1,777,068
Total loans		1,784,017
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan | 30 days past due
Loans and Allowance for Loan Losses
Past due		4,011
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan | 60 days past due
Loans and Allowance for Loan Losses
Past due		636
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan | 90 days past due
Loans and Allowance for Loan Losses
Past due		2,302
Non-acquired loans | Commercial loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans		1,280,859
Non-acquired loans | Commercial loans | Other income producing property
Loans and Allowance for Loan Losses
Total loans		218,617
Non-acquired loans | Consumer
Loans and Allowance for Loan Losses
Total loans		3,189,840
Non-acquired loans | Consumer | Real estate
Loans and Allowance for Loan Losses
Total loans		2,637,467
Non-acquired loans | Consumer | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Past due		3,866
Current		2,114,973
Total loans		2,118,839
Non-acquired loans | Consumer | Consumer Owner Occupied Loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		1,157
Non-acquired loans | Consumer | Consumer Owner Occupied Loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		285
Non-acquired loans | Consumer | Consumer Owner Occupied Loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		2,424
Non-acquired loans | Consumer | Home equity loans
Loans and Allowance for Loan Losses
Past due		1,944
Current		516,684
Total loans		518,628
Non-acquired loans | Consumer | Home equity loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		1,343
Non-acquired loans | Consumer | Home equity loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		39
Non-acquired loans | Consumer | Home equity loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		562
Non-acquired loans | Consumer | Consumer
Loans and Allowance for Loan Losses
Past due		1,936
Current		536,545
Total loans		538,481
Non-acquired loans | Consumer | Consumer | 30 days past due
Loans and Allowance for Loan Losses
Past due		825
Non-acquired loans | Consumer | Consumer | 60 days past due
Loans and Allowance for Loan Losses
Past due		285
Non-acquired loans | Consumer | Consumer | 90 days past due
Loans and Allowance for Loan Losses
Past due		826
Non-acquired loans | Consumer | Other loans
Loans and Allowance for Loan Losses
Past due		28
Current		13,864
Total loans		13,892
Non-acquired loans | Consumer | Other loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		25
Non-acquired loans | Consumer | Other loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		3
Acquired non-credit impaired loans
Loans and Allowance for Loan Losses
Past due		13,916
Current		1,746,511
Total loans		1,760,427	2,594,826
Acquired non-credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		3,147
Acquired non-credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		7,180
Acquired non-credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		3,589
Acquired non-credit impaired loans | Construction and land development
Loans and Allowance for Loan Losses
Total loans		33,569	165,070
Acquired non-credit impaired loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Total loans		447,441	679,253
Acquired non-credit impaired loans | Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Total loans		307,193	421,841
Acquired non-credit impaired loans | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Total loans		496,431	628,813
Acquired non-credit impaired loans | Home equity loans
Loans and Allowance for Loan Losses
Total loans		188,732	242,425
Acquired non-credit impaired loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans		101,880	212,537
Acquired non-credit impaired loans | Other income producing property
Loans and Allowance for Loan Losses
Past due		5,238
Current		90,459
Total loans		95,697	133,110
Acquired non-credit impaired loans | Other income producing property | 30 days past due
Loans and Allowance for Loan Losses
Past due		378
Acquired non-credit impaired loans | Other income producing property | 60 days past due
Loans and Allowance for Loan Losses
Past due		4,309
Acquired non-credit impaired loans | Other income producing property | 90 days past due
Loans and Allowance for Loan Losses
Past due		551
Acquired non-credit impaired loans | Consumer
Loans and Allowance for Loan Losses
Total loans		89,484	111,777
Acquired non-credit impaired loans | Commercial loans
Loans and Allowance for Loan Losses
Past due		2,290
Current		304,903
Total loans		985,780
Acquired non-credit impaired loans | Commercial loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		890
Acquired non-credit impaired loans | Commercial loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		702
Acquired non-credit impaired loans | Commercial loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		698
Acquired non-credit impaired loans | Commercial loans | Construction and land development
Loans and Allowance for Loan Losses
Past due		276
Current		33,293
Total loans		33,569
Acquired non-credit impaired loans | Commercial loans | Construction and land development | 30 days past due
Loans and Allowance for Loan Losses
Past due		20
Acquired non-credit impaired loans | Commercial loans | Construction and land development | 90 days past due
Loans and Allowance for Loan Losses
Past due		256
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Past due		1,366
Current		446,075
Total loans		447,441
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied | 30 days past due
Loans and Allowance for Loan Losses
Past due		144
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied | 60 days past due
Loans and Allowance for Loan Losses
Past due		1,146
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied | 90 days past due
Loans and Allowance for Loan Losses
Past due		76
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Total loans		307,193
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial
Loans and Allowance for Loan Losses
Past due		314
Current		101,566
Total loans		101,880
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial | 30 days past due
Loans and Allowance for Loan Losses
Past due		93
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial | 60 days past due
Loans and Allowance for Loan Losses
Past due		204
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial | 90 days past due
Loans and Allowance for Loan Losses
Past due		17
Acquired non-credit impaired loans | Commercial loans | Other income producing property
Loans and Allowance for Loan Losses
Total loans		95,697
Acquired non-credit impaired loans | Consumer
Loans and Allowance for Loan Losses
Total loans		774,647
Acquired non-credit impaired loans | Consumer | Real estate
Loans and Allowance for Loan Losses
Total loans		685,163
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Past due		1,333
Current		495,098
Total loans		496,431
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		768
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		151
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		414
Acquired non-credit impaired loans | Consumer | Home equity loans
Loans and Allowance for Loan Losses
Past due		1,578
Current		187,154
Total loans		188,732
Acquired non-credit impaired loans | Consumer | Home equity loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		369
Acquired non-credit impaired loans | Consumer | Home equity loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		55
Acquired non-credit impaired loans | Consumer | Home equity loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		1,154
Acquired non-credit impaired loans | Consumer | Consumer
Loans and Allowance for Loan Losses
Past due		1,521
Current		87,963
Total loans		89,484
Acquired non-credit impaired loans | Consumer | Consumer | 30 days past due
Loans and Allowance for Loan Losses
Past due		485
Acquired non-credit impaired loans | Consumer | Consumer | 60 days past due
Loans and Allowance for Loan Losses
Past due		613
Acquired non-credit impaired loans | Consumer | Consumer | 90 days past due
Loans and Allowance for Loan Losses
Past due		423
Acquired credit impaired loans
Loans and Allowance for Loan Losses
Past due		17,460
Current		344,386
Total loans		361,846	489,723
Acquired credit impaired loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		6,059
Acquired credit impaired loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		2,169
Acquired credit impaired loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		9,232
Acquired credit impaired loans | Construction and land development
Loans and Allowance for Loan Losses
Total loans		25,032	32,942
Acquired credit impaired loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans		7,029	10,043
Acquired credit impaired loans | Consumer
Loans and Allowance for Loan Losses
Total loans		35,488	42,492
Acquired credit impaired loans | Commercial loans
Loans and Allowance for Loan Losses
Past due		1,103
Current		5,926
Acquired credit impaired loans | Commercial loans | 30 days past due
Loans and Allowance for Loan Losses
Past due		118
Acquired credit impaired loans | Commercial loans | 60 days past due
Loans and Allowance for Loan Losses
Past due		910
Acquired credit impaired loans | Commercial loans | 90 days past due
Loans and Allowance for Loan Losses
Past due		75
Acquired credit impaired loans | Commercial loans | Real estate
Loans and Allowance for Loan Losses
Total loans		130,938	196,764
Acquired credit impaired loans | Commercial loans | Construction and land development
Loans and Allowance for Loan Losses
Past due		393
Current		24,639
Total loans		25,032
Acquired credit impaired loans | Commercial loans | Construction and land development | 90 days past due
Loans and Allowance for Loan Losses
Past due		393
Acquired credit impaired loans | Commercial loans | Commercial non-owner occupied
Loans and Allowance for Loan Losses
Past due		4,942
Current		125,996
Acquired credit impaired loans | Commercial loans | Commercial non-owner occupied | 30 days past due
Loans and Allowance for Loan Losses
Past due		2,283
Acquired credit impaired loans | Commercial loans | Commercial non-owner occupied | 90 days past due
Loans and Allowance for Loan Losses
Past due		2,659
Acquired credit impaired loans | Commercial loans | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans		7,029
Acquired credit impaired loans | Consumer
Loans and Allowance for Loan Losses
Past due		1,637
Current		33,851
Acquired credit impaired loans | Consumer | 30 days past due
Loans and Allowance for Loan Losses
Past due		820
Acquired credit impaired loans | Consumer | 60 days past due
Loans and Allowance for Loan Losses
Past due		283
Acquired credit impaired loans | Consumer | 90 days past due
Loans and Allowance for Loan Losses
Past due		534
Acquired credit impaired loans | Consumer | Real estate
Loans and Allowance for Loan Losses
Total loans		163,359	$ 207,482
Acquired credit impaired loans | Consumer | Commercial and industrial
Loans and Allowance for Loan Losses
Total loans		7,029
Acquired credit impaired loans | Consumer | Consumer
Loans and Allowance for Loan Losses
Total loans		$ 35,488

Loans - Nonaccrual loans (Detai

Loans - Nonaccrual loans (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2020
Loans
Total loans on nonaccrual status		$ 95,188,000	$ 33,141,000
Greater than 90 Days Accruing		11,651,000
Non-accrual with no allowance		11,253,000
Addition of loans formerly accounted for as credit impaired loans		21,000,000
Loans		$ 24,206,825,000	11,313,113,000
Number of months generally required to return to accruing status		6 months
Decrease in overall collateral dependent loans			(14,900,000)
Loans individually evaluated for impairment	$ 1,000,000			$ 500,000
CSFL
Loans
Increase in overall collateral dependent loans	$ 17,600,000
Acquired credit impaired loans | CSFL
Loans
Loans		$ 69,300,000
Commercial loans | Construction and land development
Loans
Total loans on nonaccrual status		2,421,000	1,193,000
Non-accrual with no allowance		533,000
Commercial loans | Commercial non-owner occupied
Loans
Total loans on nonaccrual status		4,596,000	1,154,000
Greater than 90 Days Accruing		471,000
Commercial loans | Commercial non-owner occupied real estate
Loans
Total loans on nonaccrual status		26,059,000	4,385,000
Non-accrual with no allowance		9,351,000
Commercial loans | Commercial and industrial
Loans
Total loans on nonaccrual status		9,218,000	6,913,000
Greater than 90 Days Accruing		10,864,000
Non-accrual with no allowance		585,000
Commercial loans | Other income producing property
Loans
Total loans on nonaccrual status		6,130,000	1,947,000
Greater than 90 Days Accruing		278,000
Non-accrual with no allowance		349,000
Consumer | Consumer Owner Occupied Loans
Loans
Total loans on nonaccrual status		30,746,000	9,718,000
Greater than 90 Days Accruing		34,000
Non-accrual with no allowance		383,000
Consumer | Home equity loans
Loans
Total loans on nonaccrual status		9,944,000	4,640,000
Non-accrual with no allowance		52,000
Consumer | Consumer
Loans
Total loans on nonaccrual status		6,074,000	$ 3,191,000
Greater than 90 Days Accruing		$ 4,000

Loans - Nonaccrual loans prior

Loans - Nonaccrual loans prior to Adoption of ASU 2016-13 (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans
Nonaccrual loans	$ 95,188	$ 33,141
Commercial loans | Construction and land development
Loans
Nonaccrual loans	2,421	1,193
Commercial loans | Commercial non-owner occupied
Loans
Nonaccrual loans	4,596	1,154
Commercial loans | Commercial non-owner occupied real estate
Loans
Nonaccrual loans	26,059	4,385
Commercial loans | Commercial and industrial
Loans
Nonaccrual loans	9,218	6,913
Commercial loans | Other income producing property
Loans
Nonaccrual loans	6,130	1,947
Consumer | Consumer Owner Occupied Loans
Loans
Nonaccrual loans	30,746	9,718
Consumer | Home equity loans
Loans
Nonaccrual loans	9,944	4,640
Consumer | Consumer
Loans
Nonaccrual loans	$ 6,074	3,191
Non-acquired loans
Loans
Nonaccrual loans		22,302
Non-acquired loans | Other income producing property
Loans
Nonaccrual loans		798
Non-acquired loans | Restructured loans
Loans
Nonaccrual loans		2,578
Non-acquired loans | Commercial loans | Construction and land development
Loans
Nonaccrual loans		363
Non-acquired loans | Commercial loans | Commercial non-owner occupied
Loans
Nonaccrual loans		732
Non-acquired loans | Commercial loans | Commercial non-owner occupied real estate
Loans
Nonaccrual loans		1,095
Non-acquired loans | Commercial loans | Commercial owner occupied real estate loan
Loans
Nonaccrual loans		3,482
Non-acquired loans | Commercial loans | Commercial and industrial
Loans
Nonaccrual loans		4,092
Non-acquired loans | Consumer | Consumer Owner Occupied Loans
Loans
Nonaccrual loans		7,202
Non-acquired loans | Consumer | Home equity loans
Loans
Nonaccrual loans		1,468
Non-acquired loans | Consumer | Real estate
Loans
Nonaccrual loans		8,670
Non-acquired loans | Consumer | Consumer
Loans
Nonaccrual loans		1,587
Acquired non-credit impaired loans
Loans
Nonaccrual loans		10,839
Acquired non-credit impaired loans | Commercial loans | Construction and land development
Loans
Nonaccrual loans		699
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied
Loans
Nonaccrual loans		393
Acquired non-credit impaired loans | Commercial loans | Commercial non-owner occupied real estate
Loans
Nonaccrual loans		1,092
Acquired non-credit impaired loans | Commercial loans | Commercial owner occupied real estate loan
Loans
Nonaccrual loans		903
Acquired non-credit impaired loans | Commercial loans | Commercial and industrial
Loans
Nonaccrual loans		722
Acquired non-credit impaired loans | Consumer | Consumer Owner Occupied Loans
Loans
Nonaccrual loans		2,350
Acquired non-credit impaired loans | Consumer | Home equity loans
Loans
Nonaccrual loans		3,067
Acquired non-credit impaired loans | Consumer | Real estate
Loans
Nonaccrual loans		5,417
Acquired non-credit impaired loans | Consumer | Other income producing property
Loans
Nonaccrual loans		1,101
Acquired non-credit impaired loans | Consumer | Consumer
Loans
Nonaccrual loans		$ 1,604

Loans - Collateral Dependent Lo

Loans - Collateral Dependent Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Loans
Collateral dependent loans	$ 6,935	$ 21,847
Collateral Coverage	8,050	46,256
Commercial non-owner occupied | Church
Loans
Collateral dependent loans		245
Collateral Coverage		$ 846
Collateral Coverage (as a percent)		345.00%
Commercial non-owner occupied | Office
Loans
Collateral dependent loans		$ 1,045
Collateral Coverage		$ 1,800
Collateral Coverage (as a percent)		172.00%
Commercial non-owner occupied | Other
Loans
Collateral dependent loans		$ 398
Collateral Coverage		$ 648
Collateral Coverage (as a percent)		163.00%
Commercial non-owner occupied | Retail
Loans
Collateral dependent loans		$ 299
Collateral Coverage		$ 1,269
Collateral Coverage (as a percent)		424.00%
Commercial owner occupied real estate loan | Industrial
Loans
Collateral dependent loans		$ 738
Collateral Coverage		$ 1,103
Collateral Coverage (as a percent)		149.00%
Commercial owner occupied real estate loan | Office
Loans
Collateral dependent loans	1,076	$ 1,076
Collateral Coverage	$ 1,485	$ 1,485
Collateral Coverage (as a percent)	138.00%	138.00%
Commercial owner occupied real estate loan | Other
Loans
Collateral dependent loans	$ 1,010	$ 3,303
Collateral Coverage	$ 1,075	$ 7,285
Collateral Coverage (as a percent)	106.00%	221.00%
Commercial owner occupied real estate loan | Retail
Loans
Collateral dependent loans	$ 4,849
Collateral Coverage	$ 5,490
Collateral Coverage (as a percent)	113.00%
Consumer Owner Occupied Loans | Other
Loans
Collateral dependent loans		$ 5,413
Collateral Coverage		$ 9,286
Collateral Coverage (as a percent)		172.00%
Home equity loans | Other
Loans
Collateral dependent loans		$ 1,768
Collateral Coverage		$ 2,679
Collateral Coverage (as a percent)		152.00%
Commercial and industrial | Industrial
Loans
Collateral dependent loans		$ 291
Collateral Coverage		$ 702
Collateral Coverage (as a percent)		241.00%
Commercial and industrial | Other
Loans
Collateral dependent loans		$ 3,696
Collateral Coverage		$ 8,442
Collateral Coverage (as a percent)		228.00%
Other income producing property | Other
Loans
Collateral dependent loans		$ 3,212
Collateral Coverage		$ 10,186
Collateral Coverage (as a percent)		317.00%
Consumer | Other
Loans
Collateral dependent loans		$ 363
Collateral Coverage		$ 525
Collateral Coverage (as a percent)		145.00%

Loans - Loans Designated as TDR

Loans - Loans Designated as TDRs (Details)	12 Months Ended
	Dec. 31, 2020USD ($)loan
Loans Designated as TDRs
Number of loans | loan	26
Pre-Modification Amortized Cost	$ 9,075,000
Post-Modification Amortized Cost	9,075,000
Balance of accruing TDRs	14,600,000
Remaining availability under commitments to lend additional funds on restructured loans	576,493
Specific reserve associated with restructured loans that subsequently defaulted	$ 1,200,000
Interest rate modification
Loans Designated as TDRs
Number of loans | loan	13
Pre-Modification Amortized Cost	$ 7,524,000
Post-Modification Amortized Cost	$ 7,524,000
Term modification
Loans Designated as TDRs
Number of loans | loan	13
Pre-Modification Amortized Cost	$ 1,551,000
Post-Modification Amortized Cost	$ 1,551,000
Commercial and industrial | Term modification
Loans Designated as TDRs
Number of loans | loan	2
Pre-Modification Amortized Cost	$ 284,000
Post-Modification Amortized Cost	$ 284,000
Consumer | Term modification
Loans Designated as TDRs
Number of loans | loan	3
Pre-Modification Amortized Cost	$ 120,000
Post-Modification Amortized Cost	$ 120,000
Commercial loans | Construction and land development | Interest rate modification
Loans Designated as TDRs
Number of loans | loan	2
Pre-Modification Amortized Cost	$ 96,000
Post-Modification Amortized Cost	$ 96,000
Commercial loans | Commercial owner occupied real estate loan | Interest rate modification
Loans Designated as TDRs
Number of loans | loan	4
Pre-Modification Amortized Cost	$ 6,905,000
Post-Modification Amortized Cost	$ 6,905,000
Commercial loans | Commercial owner occupied real estate loan | Term modification
Loans Designated as TDRs
Number of loans | loan	1
Pre-Modification Amortized Cost	$ 180,000
Post-Modification Amortized Cost	$ 180,000
Commercial loans | Commercial and industrial | Interest rate modification
Loans Designated as TDRs
Number of loans | loan	3
Pre-Modification Amortized Cost	$ 372,000
Post-Modification Amortized Cost	$ 372,000
Commercial loans | Other income producing property | Interest rate modification
Loans Designated as TDRs
Number of loans | loan	2
Pre-Modification Amortized Cost	$ 71,000
Post-Modification Amortized Cost	$ 71,000
Commercial loans | Other income producing property | Term modification
Loans Designated as TDRs
Number of loans | loan	1
Pre-Modification Amortized Cost	$ 338,000
Post-Modification Amortized Cost	$ 338,000
Consumer | Consumer Owner Occupied Loans | Interest rate modification
Loans Designated as TDRs
Number of loans | loan	1
Pre-Modification Amortized Cost	$ 28,000
Post-Modification Amortized Cost	$ 28,000
Consumer | Consumer Owner Occupied Loans | Term modification
Loans Designated as TDRs
Number of loans | loan	5
Pre-Modification Amortized Cost	$ 579,000
Post-Modification Amortized Cost	$ 579,000
Consumer | Home equity loans | Interest rate modification
Loans Designated as TDRs
Number of loans | loan	1
Pre-Modification Amortized Cost	$ 52,000
Post-Modification Amortized Cost	$ 52,000
Consumer | Home equity loans | Term modification
Loans Designated as TDRs
Number of loans | loan	1
Pre-Modification Amortized Cost	$ 50,000
Post-Modification Amortized Cost	$ 50,000

Loans - Changes in Status of Lo

Loans - Changes in Status of Loans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)loan
Loans Designated as TDRs
Paying under restructured terms - Number of Loans | loan	25
Paying under restructured terms - Amortized Cost | $	$ 8,775
Foreclosures and Defaults - Number of Loans | loan	1
Foreclosures and Defaults - Amortized Cost | $	$ 300
Interest rate modification
Loans Designated as TDRs
Paying under restructured terms - Number of Loans | loan	12
Paying under restructured terms - Amortized Cost | $	$ 7,224
Foreclosures and Defaults - Number of Loans | loan	1
Foreclosures and Defaults - Amortized Cost | $	$ 300
Term modification
Loans Designated as TDRs
Paying under restructured terms - Number of Loans | loan	13
Paying under restructured terms - Amortized Cost | $	$ 1,551

Allowance for Credit Losses (_3

Allowance for Credit Losses (ACL) - Disaggregated analysis of the changes in allowance for credit losses (Details) - USD ($) $ in Thousands	Jun. 07, 2020	Dec. 31, 2020
Allowance for credit losses
Balance at beginning of period		$ 56,927
Charge-offs		(14,602)
Recoveries		11,777
Net charge-offs		(2,825)
Provision (benefit)		89,923
Balance at end of period		457,309
Quantitative allowance
Collectively evaluated		415,929
Individually evaluated		1,249
Total quantitative allowance		417,178
Qualitative allowance		40,131
Provision for loan losses charged to operations		89,923
Unfunded Commitment
Allowance for credit losses
Provision (benefit)		43,400
Quantitative allowance
Provision for loan losses charged to operations		43,400
Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		3,408
Balance at end of period		149,404
Adjustments
Allowance for credit losses
Balance at beginning of period		111,365
Balance at end of period
Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		51,030
Balance at end of period		109,442
Residential Mortgage Sr.
Allowance for credit losses
Balance at beginning of period		6,128
Charge-offs		(528)
Recoveries		1,143
Net charge-offs		615
Provision (benefit)		4,310
Balance at end of period		63,561
Quantitative allowance
Collectively evaluated		54,656
Individually evaluated		82
Total quantitative allowance		54,738
Qualitative allowance		8,823
Provision for loan losses charged to operations		4,310
Residential Mortgage Sr. | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		406
Balance at end of period		29,935
Residential Mortgage Sr. | Adjustments
Allowance for credit losses
Balance at beginning of period		11,989
Balance at end of period
Residential Mortgage Sr. | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		5,455
Balance at end of period		16,712
Residential Mortgage Jr.
Allowance for credit losses
Balance at beginning of period		15
Charge-offs		(24)
Recoveries		455
Net charge-offs		431
Provision (benefit)		(252)
Balance at end of period		1,238
Quantitative allowance
Collectively evaluated		1,238
Total quantitative allowance		1,238
Provision for loan losses charged to operations		(252)
Residential Mortgage Jr. | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		3
Balance at end of period		804
Residential Mortgage Jr. | Adjustments
Allowance for credit losses
Balance at beginning of period		29
Balance at end of period
Residential Mortgage Jr. | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		11
Balance at end of period		226
HELOC
Allowance for credit losses
Balance at beginning of period		4,327
Charge-offs		(1,053)
Recoveries		1,251
Net charge-offs		198
Provision (benefit)		(1,311)
Balance at end of period		16,698
Quantitative allowance
Collectively evaluated		14,625
Individually evaluated		77
Total quantitative allowance		14,702
Qualitative allowance		1,996
Provision for loan losses charged to operations		(1,311)
HELOC | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		289
Balance at end of period		5,119
HELOC | Adjustments
Allowance for credit losses
Balance at beginning of period		8,465
Balance at end of period
HELOC | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		3,849
Balance at end of period		4,227
Residential Construction
Allowance for credit losses
Balance at beginning of period		815
Charge-offs		(32)
Recoveries		111
Net charge-offs		79
Provision (benefit)		(2,954)
Balance at end of period		4,914
Quantitative allowance
Collectively evaluated		4,733
Total quantitative allowance		4,733
Qualitative allowance		181
Provision for loan losses charged to operations		(2,954)
Residential Construction | Initial PCD Allowance
Allowance for credit losses
Balance at end of period		1,302
Residential Construction | Adjustments
Allowance for credit losses
Balance at beginning of period		1,594
Balance at end of period
Residential Construction | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		779
Balance at end of period		4,893
Other C&D
Allowance for credit losses
Balance at beginning of period		6,211
Charge-offs		(347)
Recoveries		1,407
Net charge-offs		1,060
Provision (benefit)		40,279
Balance at end of period		67,197
Quantitative allowance
Collectively evaluated		67,188
Individually evaluated		9
Total quantitative allowance		67,197
Provision for loan losses charged to operations		40,279
Other C&D | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		351
Balance at end of period		6,035
Other C&D | Adjustments
Allowance for credit losses
Balance at beginning of period		12,150
Balance at end of period
Other C&D | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		5,588
Balance at end of period		7,673
Consumer
Allowance for credit losses
Balance at beginning of period		4,350
Charge-offs		(6,158)
Recoveries		1,922
Net charge-offs		(4,236)
Provision (benefit)		12,333
Balance at end of period		26,562
Quantitative allowance
Collectively evaluated		18,435
Individually evaluated		120
Total quantitative allowance		18,555
Qualitative allowance		8,007
Provision for loan losses charged to operations		12,333
Consumer | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		669
Balance at end of period		6,120
Consumer | Adjustments
Allowance for credit losses
Balance at beginning of period		8,509
Balance at end of period
Consumer | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		3,490
Balance at end of period		3,836
Multifamily
Allowance for credit losses
Balance at beginning of period		1,557
Recoveries		71
Net charge-offs		71
Provision (benefit)		2,657
Balance at end of period		7,887
Quantitative allowance
Collectively evaluated		7,887
Total quantitative allowance		7,887
Provision for loan losses charged to operations		2,657
Multifamily | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		97
Balance at end of period		902
Multifamily | Adjustments
Allowance for credit losses
Balance at beginning of period		3,045
Balance at end of period
Multifamily | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		1,391
Balance at end of period		1,212
Municipal
Allowance for credit losses
Balance at beginning of period		956
Provision (benefit)		(2,282)
Balance at end of period		1,510
Quantitative allowance
Collectively evaluated		685
Total quantitative allowance		685
Qualitative allowance		825
Provision for loan losses charged to operations		(2,282)
Municipal | Initial PCD Allowance
Allowance for credit losses
Balance at end of period		1,003
Municipal | Adjustments
Allowance for credit losses
Balance at beginning of period		1,870
Balance at end of period
Municipal | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		914
Balance at end of period		919
CRE Owner Occupied
Allowance for credit losses
Balance at beginning of period		10,879
Charge-offs		(1,205)
Recoveries		1,089
Net charge-offs		(116)
Provision (benefit)		16,468
Balance at end of period		97,104
Quantitative allowance
Collectively evaluated		91,106
Individually evaluated		948
Total quantitative allowance		92,054
Qualitative allowance		5,050
Provision for loan losses charged to operations		16,468
CRE Owner Occupied | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		898
Balance at end of period		34,077
CRE Owner Occupied | Adjustments
Allowance for credit losses
Balance at beginning of period		21,282
Balance at end of period
CRE Owner Occupied | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		9,505
Balance at end of period		25,393
Non Owner Occupied CRE
Allowance for credit losses
Balance at beginning of period		15,219
Charge-offs		(601)
Recoveries		518
Net charge-offs		(83)
Provision (benefit)		13,877
Balance at end of period		124,421
Quantitative allowance
Collectively evaluated		116,571
Individually evaluated		6
Total quantitative allowance		116,577
Qualitative allowance		7,844
Provision for loan losses charged to operations		13,877
Non Owner Occupied CRE | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		656
Balance at end of period		45,787
Non Owner Occupied CRE | Adjustments
Allowance for credit losses
Balance at beginning of period		29,773
Balance at end of period
Non Owner Occupied CRE | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		13,898
Balance at end of period		35,067
C & I
Allowance for credit losses
Balance at beginning of period		6,470
Charge-offs		(4,654)
Recoveries		3,810
Net charge-offs		(844)
Provision (benefit)		6,798
Balance at end of period		46,217
Quantitative allowance
Collectively evaluated		38,805
Individually evaluated		7
Total quantitative allowance		38,812
Qualitative allowance		7,405
Provision for loan losses charged to operations		6,798
C & I | Initial PCD Allowance
Allowance for credit losses
Balance at beginning of period		39
Balance at end of period		18,320
C & I | Adjustments
Allowance for credit losses
Balance at beginning of period		12,659
Balance at end of period
C & I | Adjustments | ASU 2016-13
Allowance for credit losses
Balance at beginning of period		6,150
Balance at end of period		9,284
CSFL
Allowance for credit losses
Charge-offs	$ (158,200)
CSFL | Unfunded Commitment
Allowance for credit losses
Provision (benefit)		9,600
Quantitative allowance
Provision for loan losses charged to operations		$ 9,600

Allowance for Credit Losses (_4

Allowance for Credit Losses (ACL) - Aggregated analysis of the changes in allowance for loan losses Summary (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for credit losses
Balance at beginning of period	$ 56,927
Loans charged-off	(14,602)
Recoveries of loans previously charged off	11,777
Net charge-offs	(2,825)
Provision for loan losses charged to operations	89,923
Balance at end of period	457,309	$ 56,927
Previous Accounting Guidance [Member]
Allowance for credit losses
Balance at beginning of period	61,991	55,798	$ 48,075
Loans charged-off		(9,775)	(8,226)
Recoveries of loans previously charged off		3,914	3,300
Net charge-offs		(5,861)	(4,926)
Provision for loan losses charged to operations		12,777	13,783
Reduction due to loan removals		(723)	(1,134)
Balance at end of period		61,991	55,798
Non-acquired loans
Allowance for credit losses
Balance at beginning of period	56,927	51,194	43,448
Loans charged-off		(6,917)	(6,012)
Recoveries of loans previously charged off		3,367	2,995
Provision for loan losses charged to operations		9,283	10,763
Balance at end of period		56,927	51,194
Non-acquired loans | Previous Accounting Guidance [Member]
Allowance for credit losses
Balance at beginning of period	56,927	51,194	43,448
Loans charged-off		(6,917)	(6,012)
Recoveries of loans previously charged off		3,367	2,995
Net charge-offs		(3,550)	(3,017)
Provision for loan losses charged to operations		9,283	10,763
Balance at end of period		56,927	51,194
Acquired non-credit impaired loans
Allowance for credit losses
Loans charged-off		(2,858)	(2,214)
Recoveries of loans previously charged off		547	305
Provision for loan losses charged to operations		2,311	1,909
Acquired non-credit impaired loans | Previous Accounting Guidance [Member]
Allowance for credit losses
Loans charged-off		(2,858)	(2,214)
Recoveries of loans previously charged off		547	305
Net charge-offs		(2,311)	(1,909)
Provision for loan losses charged to operations		2,311	1,909
Acquired credit impaired loans
Allowance for credit losses
Balance at beginning of period	5,064	4,604	4,627
Provision for loan losses charged to operations		1,183	1,111
Balance at end of period		5,064	4,604
Acquired credit impaired loans | Previous Accounting Guidance [Member]
Allowance for credit losses
Balance at beginning of period	$ 5,064	4,604	4,627
Provision for loan losses charged to operations		1,183	1,111
Reduction due to loan removals		(723)	(1,134)
Balance at end of period		$ 5,064	$ 4,604

Allowance for Credit Losses (_5

Allowance for Credit Losses (ACL) - Aggregated analysis of the changes in allowance for loan losses Details (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2020	Mar. 31, 2020
Allowance for loan losses:
Balance at beginning of period	$ 56,927,000
Charge-offs	(14,602,000)
Recoveries	11,777,000
Provision (benefit)	89,923,000
Balance at end of period	457,309,000	$ 56,927,000
Loans individually evaluated for impairment	1,249,000
Loans collectively evaluated for impairment	415,929,000
Loans
Loans individually evaluated for impairment				$ 1,000,000	$ 500,000
Total loans	24,664,134,000	11,375,104,000
Construction and land development | Commercial loans
Loans
Total loans	1,899,066,000	1,017,261,000
Commercial non-owner occupied | Commercial loans
Loans
Total loans	5,931,323,000	2,323,967,000
Consumer Owner Occupied Loans | Consumer
Loans
Total loans	4,108,042,000	2,706,960,000
Home equity loans | Consumer
Loans
Total loans	1,336,689,000	758,020,000
Commercial and industrial | Commercial loans
Loans
Total loans	5,047,147,000	1,386,327,000
Other income producing property | Commercial loans
Loans
Total loans	587,448,000	346,554,000
Consumer | Consumer
Loans
Total loans	894,334,000	663,422,000
Other loans | Consumer
Loans
Total loans	17,993,000	13,892,000
Non-acquired loans
Allowance for loan losses:
Balance at beginning of period	56,927,000	51,194,000	$ 43,448,000
Charge-offs		(6,917,000)	(6,012,000)
Recoveries		3,367,000	2,995,000
Provision (benefit)		9,283,000	10,763,000
Balance at end of period		56,927,000	51,194,000
Loans individually evaluated for impairment		1,346,000	1,628,000
Loans collectively evaluated for impairment		55,581,000	49,566,000
Loans
Loans individually evaluated for impairment		58,532,000	57,018,000
Loans collectively evaluated for impairment		9,194,299,000	7,876,268,000
Total loans		9,252,831,000	7,933,286,000
Non-acquired loans | Commercial loans
Loans
Total loans		6,062,991,000
Non-acquired loans | Consumer
Loans
Total loans		3,189,840,000
Non-acquired loans | Real estate | Consumer
Loans
Total loans		2,637,467,000
Non-acquired loans | Construction and land development
Allowance for loan losses:
Balance at beginning of period	6,104,000	5,682,000	5,921,000
Charge-offs		(78,000)	(76,000)
Recoveries		1,016,000	1,340,000
Provision (benefit)		(516,000)	(1,503,000)
Balance at end of period		6,104,000	5,682,000
Loans individually evaluated for impairment		617,000	788,000
Loans collectively evaluated for impairment		5,487,000	4,894,000
Loans
Loans individually evaluated for impairment		35,201,000	37,913,000
Loans collectively evaluated for impairment		933,159,000	803,532,000
Total loans		968,360,000	841,445,000
Non-acquired loans | Construction and land development | Commercial loans
Loans
Total loans		968,360,000
Non-acquired loans | Commercial non-owner occupied
Allowance for loan losses:
Balance at beginning of period	10,699,000	8,754,000	6,525,000
Charge-offs		(3,000)
Recoveries		76,000	11,000
Provision (benefit)		1,872,000	2,218,000
Balance at end of period		10,699,000	8,754,000
Loans individually evaluated for impairment			70,000
Loans collectively evaluated for impairment		10,699,000	8,684,000
Loans
Loans individually evaluated for impairment		379,000	1,025,000
Loans collectively evaluated for impairment		1,810,759,000	1,414,526,000
Total loans		1,811,138,000	1,415,551,000
Non-acquired loans | Commercial non-owner occupied | Commercial loans
Loans
Total loans		1,811,138,000
Non-acquired loans | Commercial owner occupied real estate loan
Allowance for loan losses:
Balance at beginning of period	10,581,000	9,369,000	8,128,000
Charge-offs		(87,000)	(659,000)
Recoveries		174,000	145,000
Provision (benefit)		1,125,000	1,755,000
Balance at end of period		10,581,000	9,369,000
Loans individually evaluated for impairment		24,000	27,000
Loans collectively evaluated for impairment		10,557,000	9,342,000
Loans
Loans individually evaluated for impairment		6,575,000	4,142,000
Loans collectively evaluated for impairment		1,777,442,000	1,513,409,000
Total loans		1,784,017,000	1,517,551,000
Non-acquired loans | Commercial owner occupied real estate loan | Commercial loans
Loans
Total loans		1,784,017,000
Non-acquired loans | Consumer Owner Occupied Loans
Allowance for loan losses:
Balance at beginning of period	12,596,000	11,913,000	9,668,000
Charge-offs		(50,000)	(80,000)
Recoveries		213,000	132,000
Provision (benefit)		520,000	2,193,000
Balance at end of period		12,596,000	11,913,000
Loans individually evaluated for impairment		102,000	41,000
Loans collectively evaluated for impairment		12,494,000	11,872,000
Loans
Loans individually evaluated for impairment		5,141,000	6,761,000
Loans collectively evaluated for impairment		2,113,698,000	1,929,504,000
Total loans		2,118,839,000	1,936,265,000
Non-acquired loans | Consumer Owner Occupied Loans | Consumer
Loans
Total loans		2,118,839,000
Non-acquired loans | Home equity loans
Allowance for loan losses:
Balance at beginning of period	3,188,000	3,434,000	3,250,000
Charge-offs		(203,000)	(215,000)
Recoveries		265,000	279,000
Provision (benefit)		(308,000)	120,000
Balance at end of period		3,188,000	3,434,000
Loans individually evaluated for impairment		132,000	142,000
Loans collectively evaluated for impairment		3,056,000	3,292,000
Loans
Loans individually evaluated for impairment		2,461,000	2,826,000
Loans collectively evaluated for impairment		516,167,000	492,322,000
Total loans		518,628,000	495,148,000
Non-acquired loans | Home equity loans | Consumer
Loans
Total loans		518,628,000
Non-acquired loans | Commercial and industrial
Allowance for loan losses:
Balance at beginning of period	8,339,000	7,454,000	5,488,000
Charge-offs		(622,000)	(500,000)
Recoveries		351,000	256,000
Provision (benefit)		1,156,000	2,210,000
Balance at end of period		8,339,000	7,454,000
Loans individually evaluated for impairment		366,000	416,000
Loans collectively evaluated for impairment		7,973,000	7,038,000
Loans
Loans individually evaluated for impairment		6,578,000	1,291,000
Loans collectively evaluated for impairment		1,274,281,000	1,053,661,000
Total loans		1,280,859,000	1,054,952,000
Non-acquired loans | Commercial and industrial | Commercial loans
Loans
Total loans		1,280,859,000
Non-acquired loans | Other income producing property
Allowance for loan losses:
Balance at beginning of period	1,336,000	1,446,000	1,375,000
Charge-offs		(31,000)	(2,000)
Recoveries		94,000	21,000
Provision (benefit)		(173,000)	52,000
Balance at end of period		1,336,000	1,446,000
Loans individually evaluated for impairment		50,000	142,000
Loans collectively evaluated for impairment		1,286,000	1,304,000
Loans
Loans individually evaluated for impairment		2,024,000	2,872,000
Loans collectively evaluated for impairment		216,593,000	211,481,000
Total loans		218,617,000	214,353,000
Non-acquired loans | Other income producing property | Commercial loans
Loans
Total loans		218,617,000
Non-acquired loans | Consumer
Allowance for loan losses:
Balance at beginning of period	3,947,000	3,101,000	2,788,000
Charge-offs		(5,843,000)	(4,480,000)
Recoveries		1,178,000	811,000
Provision (benefit)		5,511,000	3,982,000
Balance at end of period		3,947,000	3,101,000
Loans individually evaluated for impairment		55,000	2,000
Loans collectively evaluated for impairment		3,892,000	3,099,000
Loans
Loans individually evaluated for impairment		173,000	188,000
Loans collectively evaluated for impairment		538,308,000	448,476,000
Total loans		538,481,000	448,664,000
Non-acquired loans | Consumer | Consumer
Loans
Total loans		538,481,000
Non-acquired loans | Other loans
Allowance for loan losses:
Balance at beginning of period	137,000	41,000	305,000
Provision (benefit)		96,000	(264,000)
Balance at end of period		137,000	41,000
Loans collectively evaluated for impairment		137,000	41,000
Loans
Loans collectively evaluated for impairment		13,892,000	9,357,000
Total loans		13,892,000	9,357,000
Non-acquired loans | Other loans | Consumer
Loans
Total loans		13,892,000
Acquired non-credit impaired loans
Allowance for loan losses:
Charge-offs		(2,858,000)	(2,214,000)
Recoveries		547,000	305,000
Provision (benefit)		2,311,000	1,909,000
Loans
Loans collectively evaluated for impairment		1,760,427,000	2,594,826,000
Total loans		1,760,427,000	2,594,826,000
Acquired non-credit impaired loans | Commercial loans
Loans
Total loans		985,780,000
Acquired non-credit impaired loans | Consumer
Loans
Total loans		774,647,000
Acquired non-credit impaired loans | Real estate | Consumer
Loans
Total loans		685,163,000
Acquired non-credit impaired loans | Construction and land development
Allowance for loan losses:
Charge-offs		(44,000)	(107,000)
Recoveries		3,000	8,000
Provision (benefit)		41,000	99,000
Loans
Loans collectively evaluated for impairment		33,569,000	165,070,000
Total loans		33,569,000	165,070,000
Acquired non-credit impaired loans | Construction and land development | Commercial loans
Loans
Total loans		33,569,000
Acquired non-credit impaired loans | Commercial non-owner occupied
Loans
Loans collectively evaluated for impairment		447,441,000	679,253,000
Total loans		447,441,000	679,253,000
Acquired non-credit impaired loans | Commercial non-owner occupied | Commercial loans
Loans
Total loans		447,441,000
Acquired non-credit impaired loans | Commercial owner occupied real estate loan
Allowance for loan losses:
Charge-offs		(786,000)	(28,000)
Provision (benefit)		786,000	28,000
Loans
Loans collectively evaluated for impairment		307,193,000	421,841,000
Total loans		307,193,000	421,841,000
Acquired non-credit impaired loans | Commercial owner occupied real estate loan | Commercial loans
Loans
Total loans		307,193,000
Acquired non-credit impaired loans | Consumer Owner Occupied Loans
Allowance for loan losses:
Charge-offs		(6,000)	(70,000)
Recoveries		26,000	64,000
Provision (benefit)		(20,000)	6,000
Loans
Loans collectively evaluated for impairment		496,431,000	628,813,000
Total loans		496,431,000	628,813,000
Acquired non-credit impaired loans | Consumer Owner Occupied Loans | Consumer
Loans
Total loans		496,431,000
Acquired non-credit impaired loans | Home equity loans
Allowance for loan losses:
Charge-offs		(263,000)	(436,000)
Recoveries		206,000	102,000
Provision (benefit)		57,000	334,000
Loans
Loans collectively evaluated for impairment		188,732,000	242,425,000
Total loans		188,732,000	242,425,000
Acquired non-credit impaired loans | Home equity loans | Consumer
Loans
Total loans		188,732,000
Acquired non-credit impaired loans | Commercial and industrial
Allowance for loan losses:
Charge-offs		(1,289,000)	(1,108,000)
Recoveries		190,000	63,000
Provision (benefit)		1,099,000	1,045,000
Loans
Loans collectively evaluated for impairment		101,880,000	212,537,000
Total loans		101,880,000	212,537,000
Acquired non-credit impaired loans | Commercial and industrial | Commercial loans
Loans
Total loans		101,880,000
Acquired non-credit impaired loans | Other income producing property
Allowance for loan losses:
Charge-offs		(26,000)
Recoveries		71,000
Provision (benefit)		(45,000)
Loans
Loans collectively evaluated for impairment		95,697,000	133,110,000
Total loans		95,697,000	133,110,000
Acquired non-credit impaired loans | Other income producing property | Commercial loans
Loans
Total loans		95,697,000
Acquired non-credit impaired loans | Consumer
Allowance for loan losses:
Charge-offs		(444,000)	(465,000)
Recoveries		51,000	68,000
Provision (benefit)		393,000	397,000
Loans
Loans collectively evaluated for impairment		89,484,000	111,777,000
Total loans		89,484,000	111,777,000
Acquired non-credit impaired loans | Consumer | Consumer
Loans
Total loans		89,484,000
Acquired credit impaired loans
Allowance for loan losses:
Balance at beginning of period	5,064,000	4,604,000	4,627,000
Provision (benefit)		1,183,000	1,111,000
Reduction due to loan removals		(723,000)	(1,134,000)
Balance at end of period		5,064,000	4,604,000
Loans collectively evaluated for impairment		5,064,000	4,604,000
Loans
Loans collectively evaluated for impairment		361,846,000	489,723,000
Total loans		361,846,000	489,723,000
Acquired credit impaired loans | Real estate | Commercial loans
Allowance for loan losses:
Balance at beginning of period	1,377,000	801,000	288,000
Provision (benefit)		577,000	532,000
Reduction due to loan removals		(1,000)	(19,000)
Balance at end of period		1,377,000	801,000
Loans collectively evaluated for impairment		1,377,000	801,000
Loans
Loans collectively evaluated for impairment		130,938,000	196,764,000
Total loans		130,938,000	196,764,000
Acquired credit impaired loans | Real estate | Consumer
Allowance for loan losses:
Balance at beginning of period	2,555,000	2,246,000	3,553,000
Provision (benefit)		716,000	(892,000)
Reduction due to loan removals		(407,000)	(415,000)
Balance at end of period		2,555,000	2,246,000
Loans collectively evaluated for impairment		2,555,000	2,246,000
Loans
Loans collectively evaluated for impairment		163,359,000	207,482,000
Total loans		163,359,000	207,482,000
Acquired credit impaired loans | Construction and land development
Allowance for loan losses:
Balance at beginning of period	569,000	717,000	180,000
Provision (benefit)		(148,000)	657,000
Reduction due to loan removals			(120,000)
Balance at end of period		569,000	717,000
Loans collectively evaluated for impairment		569,000	717,000
Loans
Loans collectively evaluated for impairment		25,032,000	32,942,000
Total loans		25,032,000	32,942,000
Acquired credit impaired loans | Construction and land development | Commercial loans
Loans
Total loans		25,032,000
Acquired credit impaired loans | Commercial and industrial
Allowance for loan losses:
Balance at beginning of period	24,000	79,000	145,000
Provision (benefit)		260,000	511,000
Reduction due to loan removals		(315,000)	(577,000)
Balance at end of period		24,000	79,000
Loans collectively evaluated for impairment		24,000	79,000
Loans
Loans collectively evaluated for impairment		7,029,000	10,043,000
Total loans		7,029,000	10,043,000
Acquired credit impaired loans | Commercial and industrial | Commercial loans
Loans
Total loans		7,029,000
Acquired credit impaired loans | Commercial and industrial | Consumer
Loans
Total loans		7,029,000
Acquired credit impaired loans | Consumer
Allowance for loan losses:
Balance at beginning of period	$ 539,000	761,000	461,000
Provision (benefit)		(222,000)	303,000
Reduction due to loan removals			(3,000)
Balance at end of period		539,000	761,000
Loans collectively evaluated for impairment		539,000	761,000
Loans
Loans collectively evaluated for impairment		35,488,000	42,492,000
Total loans		35,488,000	$ 42,492,000
Acquired credit impaired loans | Consumer | Consumer
Loans
Total loans		$ 35,488,000

Other Real Estate Owned and B_3

Other Real Estate Owned and Bank Premises Held for Sale (Details)	12 Months Ended
	Dec. 31, 2020USD ($)property	Dec. 31, 2019USD ($)property	Dec. 31, 2018USD ($)
OREO and Bank Premises
Other Real Estate Owned	$ 6,539,000	$ 6,153,000
Bank Premises Held for Sale	5,425,000	5,257,000
Balance at the beginning of the period	11,964,000	11,410,000	$ 11,203,000
Additions, net	27,340,000	10,373,000	13,391,000
Writedowns	(1,085,000)	(1,192,000)	(1,420,000)
Sold	(18,610,000)	(8,627,000)	(11,974,000)
Balance at the end of the period	47,920,000	11,964,000	11,410,000
Other Real Estate Owned	11,914,000	6,539,000	6,153,000
Bank Premises Held for Sale	$ 36,006,000	$ 5,425,000	5,257,000
Number of properties held | property	42	47
Number of properties premises held for sale | property	33	12
Residential real estate consumer mortgage loans in foreclosure, carrying value	$ 5,000,000
Residential real estate
OREO and Bank Premises
Other Real Estate In Foreclosure	804,000
Park Sterling Corporation
OREO and Bank Premises
Acquired			$ 210,000
CSFL
OREO and Bank Premises
Acquired	$ 28,311,000

Premises and Equipment (Details

Premises and Equipment (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2020	Jun. 07, 2020
Premises and equipment
Total	$ 836,390,000	$ 497,725,000
Less accumulated depreciation	(257,151,000)	(180,404,000)
Net premises and equipment	579,239,000	317,321,000
Depreciation expense charged to operations	25,300,000	18,200,000	$ 18,700,000
Capitalized implementation costs related to new digital banking platform	2,100,000
Capitalized implementation costs related to new public website	743,000
2018-15
Premises and equipment
Capitalized implementation costs related to internal use software		2,900,000
CSFL
Premises and equipment
Premises and equipment				$ 330,300,000	$ 313,435,000
Land
Premises and equipment
Total	152,263,000	74,913,000
Buildings and leasehold improvements
Premises and equipment
Total	$ 406,078,000	226,750,000
Buildings and leasehold improvements | Minimum
Premises and equipment
Useful Life	15 years
Buildings and leasehold improvements | Maximum
Premises and equipment
Useful Life	40 years
Equipment and furnishings
Premises and equipment
Total	$ 161,009,000	106,696,000
Equipment and furnishings | Minimum
Premises and equipment
Useful Life	3 years
Equipment and furnishings | Maximum
Premises and equipment
Useful Life	10 years
Construction in process
Premises and equipment
Total	$ 3,618,000	1,977,000
Computer software
Premises and equipment
Useful Life	36 months
Total	$ 37,400,000	13,700,000
Depreciation expense charged to operations	2,400,000	1,200,000	$ 2,100,000
Lease right of use assets
Premises and equipment
Total	$ 113,422,000	$ 87,389,000

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Summary of changes (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Dec. 31, 2020
Goodwill and Other Intangible Assets
Impairment of goodwill	$ 0	$ 0
Goodwill
Goodwill, Beginning Balance		1,002,900
Goodwill from CenterState acquisition		561,042
Goodwill, Ending Balance		$ 1,563,942

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Summary of gross carrying amounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other intangible assets
Gross carrying amount	$ 258,554	$ 119,501
Accumulated amortization	(95,962)	(69,685)
Net carrying amount	162,592	49,816
Amortization expense	26,992	13,084	$ 14,209
Estimated amortization expense for other intangibles for each of the next five years
2021	33,845
2022	30,056
2023	24,634
2024	19,790
2025	16,480
Thereafter	37,787
Net carrying amount	$ 162,592	$ 49,816
Minimum
Other intangible assets
Estimated useful lives	2 years
Maximum
Other intangible assets
Estimated useful lives	15 years

Deposits - Total deposits (Deta

Deposits - Total deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deposits
Certificates of deposit	$ 3,743,271	$ 1,651,399
Interest-bearing demand deposits	14,539,928	5,966,496
Non-interest bearing demand deposits	9,711,338	3,245,306
Savings deposits	2,694,011	1,309,896
Other time deposits	5,334	3,999
Total deposits	$ 30,693,882	$ 12,177,096

Deposits - Certificates of depo

Deposits - Certificates of deposits and Scheduled maturities of time deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deposits
Aggregate amounts of certificates of deposits in denominations of $250,000 or more	$ 814,200	$ 303,200
Traditional, out-of-market brokered deposits	600,000	0
Other Time Deposits	5,334	$ 3,999
Scheduled maturities of time deposits of all denominations
2021	2,704,310
2022	610,282
2023	210,321
2024	97,640
2025	123,218
Thereafter	2,834
Time deposits	$ 3,748,605

Federal Funds Purchased and S_3

Federal Funds Purchased and Securities Sold Under Agreements to Repurchase (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Rate
Repurchase agreement	$ 394,900	$ 242,200
Carrying amount of the securities pledged to collateralize repurchase agreements	515,900	242,200
Federal funds purchased and securities sold under repurchase agreements
Amount
At period-end	779,666	298,741	$ 270,649
Average for the year	553,110	282,172	312,768
Maximum month-end balance	$ 779,666	$ 321,833	$ 362,047
Rate
At period-end (as a percent)	0.17%	0.90%	1.08%
Average for the year (as a percent)	0.35%	0.93%	0.75%
Federal funds purchased and securities sold under repurchase agreements | Minimum
Information concerning federal funds purchased and securities sold under repurchase agreements
Maturity period from the transaction date	1 day
Federal funds purchased and securities sold under repurchase agreements | Maximum
Information concerning federal funds purchased and securities sold under repurchase agreements
Maturity period from the transaction date	3 days
Maturity period as per policies	9 months

Other Borrowings (Details)

Other Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Borrowings
Shot-term borrowings	$ 0	$ 700,000
Long term borrowings	390,179	115,936
Total borrowings	390,179	815,936
Short term borrowings, Average balance	745,939	538,627
Long term borrowings, Average balance	271,493	116,126
Total borrowings, Average balance	$ 1,017,432	$ 654,753
Fixed interest rate (as a percent)	4.40%	2.00%
Weighted average interest rate (as a percent)	1.58%	2.57%
Junior subordinated debt securities	$ 144,300	$ 115,800
Federal Home Loan Bank Rate Credit maturing 3/4/2020
Other Borrowings
Shot-term borrowings		$ 200,000
Fixed interest rate (as a percent)		1.75%
Federal Home Loan Bank Rate Credit maturing 3/19/2020
Other Borrowings
Shot-term borrowings		$ 350,000
Fixed interest rate (as a percent)		1.73%
Federal Home Loan Bank Rate Credit Maturing Three 3/30/2020
Other Borrowings
Shot-term borrowings		$ 150,000
Fixed interest rate (as a percent)		1.72%
Short term borrowings
Other Borrowings
Fixed interest rate (as a percent)		1.73%
Weighted average interest rate (as a percent)	0.63%	2.35%
SCBT Capital Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 12,372	$ 12,372
Fixed interest rate (as a percent)	2.01%	3.68%
SCBT Capital Trust II junior subordinated debt
Other Borrowings
Long term borrowings	$ 8,248	$ 8,248
Fixed interest rate (as a percent)	2.01%	3.68%
SCBT Capital Trust III junior subordinated debt
Other Borrowings
Long term borrowings	$ 20,619	$ 20,619
Fixed interest rate (as a percent)	1.81%	3.48%
SAVB Capital Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 6,186	$ 6,186
Fixed interest rate (as a percent)	3.09%	4.84%
SAVB Capital Trust II junior subordinated debt
Other Borrowings
Long term borrowings	$ 4,124	$ 4,124
Fixed interest rate (as a percent)	2.42%	4.09%
TSB Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 3,093	$ 3,093
Fixed interest rate (as a percent)	1.94%	3.61%
Southeastern Bank Financial Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 10,310	$ 10,310
Fixed interest rate (as a percent)	1.62%	3.29%
Southeastern Bank Financial Statutory Trust II junior subordinated debt
Other Borrowings
Long term borrowings	$ 10,310	$ 10,310
Fixed interest rate (as a percent)	1.62%	3.29%
CSBC Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 15,464	$ 15,464
Fixed interest rate (as a percent)	1.79%	3.46%
Community Capital Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 10,310	$ 10,310
Fixed interest rate (as a percent)	1.77%	3.44%
FCRV Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 5,155	$ 5,155
Fixed interest rate (as a percent)	1.92%	3.59%
Provident Community Bancshares Capital Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 4,124	$ 4,124
Fixed interest rate (as a percent)	1.97%	3.84%
Provident Community Bancshares Capital Trust II junior subordinated debt
Other Borrowings
Long term borrowings	$ 8,248	$ 8,248
Fixed interest rate (as a percent)	1.97%	3.65%
CenterState Banks of Florida Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 10,310
Fixed interest rate (as a percent)	3.30%
Valrico Capital Statutory Trust junior subordinated debt
Other Borrowings
Long term borrowings	$ 2,577
Fixed interest rate (as a percent)	2.93%
Federal Trust Statutory Trust I Junior Subordinated Debt [Member]
Other Borrowings
Long term borrowings	$ 5,155
Fixed interest rate (as a percent)	3.18%
Gulfstream Bancshares Capital Trust II junior subordinated debt
Other Borrowings
Long term borrowings	$ 3,093
Fixed interest rate (as a percent)	1.93%
Homestead Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 10,495
Fixed interest rate (as a percent)	1.88%
BSA Financial Statutory Trust I junior subordinated debt
Other Borrowings
Long term borrowings	$ 5,155
Fixed interest rate (as a percent)	1.77%
MRCB Statutory Trust II junior subordinated debt
Other Borrowings
Long term borrowings	$ 3,093
Fixed interest rate (as a percent)	1.82%
Fair Market Value Discount Trust Preferred Debt Acquired
Other Borrowings
Other long term debt acquired	$ (14,116)	$ (2,730)
Junior Subordinated Debt
Other Borrowings
Long term borrowings	144,325	115,833
Long term borrowings, Average balance	$ 131,817	$ 115,490
Fixed interest rate (as a percent)	2.05%	3.60%
Weighted average interest rate (as a percent)	2.51%	4.20%
Junior Subordinated Debt | LIBOR | Minimum
Other Borrowings
Spread on variable rate basis (as a percent)	140.00%
Junior Subordinated Debt | LIBOR | Maximum
Other Borrowings
Spread on variable rate basis (as a percent)	305.00%
Residential Warranty Corp. subordinated note
Other Borrowings
Long term borrowings	$ 7,000
Fixed interest rate (as a percent)	5.00%
Messiah College subordinated note
Other Borrowings
Long term borrowings	$ 4,000
Fixed interest rate (as a percent)	5.00%
National Bank of Commerce subordinated debt
Other Borrowings
Long term borrowings	$ 25,000
Fixed interest rate (as a percent)	6.00%
National Bank of Commerce subordinated debt | LIBOR
Other Borrowings
Spread on variable rate basis (as a percent)	479.00%
Landmark Bancshares subordinated debt
Other Borrowings
Long term borrowings	$ 13,000
Fixed interest rate (as a percent)	6.50%
Landmark Bancshares subordinated debt | LIBOR
Other Borrowings
Spread on variable rate basis (as a percent)	467.00%
CenterState Bank Corporation subordinated debt
Other Borrowings
Long term borrowings	$ 200,000
Debt issuance cost	$ (3,100)
Fixed interest rate (as a percent)	5.75%
Junior subordinated debt securities	$ 196,900
CenterState Bank Corporation subordinated debt | LIBOR
Other Borrowings
Fixed interest rate (as a percent)	5.75%
Spread on variable rate basis (as a percent)	562.00%
Subordinated Debt
Other Borrowings
Long term borrowings	$ 245,854
Debt issuance cost	(3,146)
Long term borrowings, Average balance	$ 139,584
Fixed interest rate (as a percent)	5.78%
Weighted average interest rate (as a percent)	5.69%
Other
Other Borrowings
Long term borrowings		$ 103
Long term borrowings, Average balance	$ 92	$ 636
Fixed interest rate (as a percent)		0.50%
Weighted average interest rate (as a percent)	0.50%	6.02%
Long term borrowings
Other Borrowings
Fixed interest rate (as a percent)		3.60%
Weighted average interest rate (as a percent)	3.60%	3.60%

Other Borrowings - Short-Term B

Other Borrowings - Short-Term Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
FHLB Advances
Outstanding advances	$ 0	$ 0	$ 700,000
Shot-term borrowings	0	$ 0	$ 700,000
Short term borrowings
FHLB Advances
Long-term Debt, Weighted Average Interest Rate, over Time		0.63%
FHLB Advances
FHLB Advances
Loans pledged via a blanket lien to the FHLB for advances and letters of credit	3,600,000	$ 3,600,000
Investment securities pledged	346,600	346,600
Total borrowing capacity at FHLB	2,800,000	2,800,000
Letter of credit borrowed	12,200	12,200
Unused net credit available with the FHLB	2,800,000	2,800,000
Long-term Debt, Weighted Average Interest Rate, at Point in Time			1.73%
Long-term Debt, Weighted Average Interest Rate, over Time			2.35%
Average amount of FHLB advances outstanding		745,900	$ 538,600
Payments of FHLB advances	700,000
FHLB Advances | Interest rate swap
FHLB Advances
Non- interest expense	38,800
FRB Borrowings
FHLB Advances
Letter of credit borrowed	0	0
Maximum borrowing capacity	1,200,000	1,200,000
Loans secured by blanket lien	$ 2,000,000	$ 2,000,000

Other Borrowings - Junior Subor

Other Borrowings - Junior Subordinated Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Junior Subordinated Debt
Junior subordinated debt securities	$ 144.3	$ 115.8
Discount	$ 14.1	$ 2.7
Junior Subordinated Debt
Junior Subordinated Debt
Debt instrument term	5 years
Long-term Debt, Weighted Average Interest Rate, at Point in Time	2.05%	3.60%
Long-term Debt, Weighted Average Interest Rate, over Time	2.51%	4.20%
Junior Subordinated Debt net of discount
Junior Subordinated Debt
Long-term Debt, Weighted Average Interest Rate, over Time	3.56%	4.88%
Trusts | Junior Subordinated Debt
Junior Subordinated Debt
Junior subordinated debt securities	$ 144.3
Discount amortization period	1 year 6 months
Amount of trust preferred securities excluded from Tier 1 capital	$ 158.4
SAVB Capital Trust I and II and FFCH Capital Trust I | Junior Subordinated Debt
Junior Subordinated Debt
Liability for the junior subordinated debt securities recorded on SAVB Capital Trust I and II	144.3
Discount	14.1
Amount paid to holders, if the entity call backs the subordinated debt securities	$ 158.4
Discount amortization period	5 years
SAVB Capital Trust I and II | Junior Subordinated Debt
Junior Subordinated Debt
Discount amortization period	14 years 6 months

Other Borrowings - Subordinated

Other Borrowings - Subordinated Debt and Notes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CenterState Bank Corporation subordinated debt
Other Borrowings
Subordinated Debt	$ 200,000
Debt issuance cost	3,100
Subordinated Debt
Other Borrowings
Subordinated Debt	245,900	$ 0
Debt issuance cost	$ 3,146
Discount amortization period	8 years 6 months
Weighted average cost of the subordinated debt	5.78%
Weighted average cost year to date	5.69%
Subordinated debt qualify for Tier 2	$ 238,000
Subordinated debt do not qualify for Tier 2	$ 11,000
Subordinated Debt net of discount
Other Borrowings
Weighted average cost year to date	5.93%

Other Borrowings - Lines of Cre

Other Borrowings - Lines of Credit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Nov. 15, 2019
Principal maturities of other borrowings
2020	$ 11,000
Thereafter	379,179
Total borrowings	$ 390,179	$ 700,103
Unsecured line of credit
Other Borrowings
Maximum borrowing capacity			$ 100,000
Interest rate	2.00%
Letter of credit outstanding	$ 0	$ 0
Junior Subordinated Debt
Principal maturities of other borrowings
Thereafter	144,325
Total borrowings	144,325
FHLB Advances
Other Borrowings
Letter of credit outstanding	12,200
Subordinated Debt
Principal maturities of other borrowings
2020	11,000
Thereafter	234,854
Total borrowings	$ 245,854
LIBOR | Unsecured line of credit
Other Borrowings
Spread on variable rate basis (as a percent)	0.00%

Income Taxes - Provision for in

Income Taxes - Provision for income taxes breakup (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ 16,245	$ 40,375	$ 25,275
State	13,296	4,965	6,783
Total current tax expense	29,541	45,340	32,058
Deferred:
Federal	(36,801)	(1,598)	12,557
State	(9,400)	200	769
Total deferred tax (benefit) expense	(46,201)	(1,398)	13,326
(Benefit) provision for income taxes	$ (16,660)	$ 43,942	$ 45,384
Federal statutory income tax rate (as a percent)	21.00%	21.00%	21.00%	35.00%

Income Taxes - Provision for _2

Income Taxes - Provision for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Difference between the provision for income taxes and taxes computed by applying the federal statutory income tax rate to income before provision for income taxes
Income taxes at federal statutory rate	$ 21,834	$ 48,389	$ 47,094
Increase (reduction) of taxes resulting from:
State income taxes, net of federal tax benefit	3,077	4,080	5,916
Non- deductible merger expenses	1,344
Increase in cash surrender value of BOLI policies	(2,389)	(1,210)	(1,261)
Tax-exempt interest	(2,257)	(1,877)	(2,037)
Income tax credits	(7,138)	(6,881)	(3,118)
Non-deductible FDIC premiums	1,364	133	191
Non-deductible executive compensation	1,016	315	305
Revaluation of net deferred tax asset due to tax law change			(991)
Benefit of tax loss carryback under CARES Act	(31,468)
Other, net	(2,043)	993	(715)
(Benefit) provision for income taxes	(16,660)	43,942	$ 45,384
Components of the net deferred tax asset
Allowance for loan losses	119,602	14,468
Other-than-temporary impairment on securities	268	250
Share-based compensation	2,807	4,975
Pension plan and post-retirement benefits	516	494
Deferred compensation	13,671	12,475
Purchase accounting adjustments	11,772	24,530
Other real estate owned	899	380
Net operating loss and tax credit carryforwards	26,229	10,347
Deferred loan fees and costs	12,826
Nonaccrual Interest	3,141
Lease liability	28,179	19,146
Cash flow hedge		3,034
Other	603	1,040
Total deferred tax assets	220,513	91,139
Unrealized gains on investment securities available for sale	13,026	2,373
Depreciation	18,326	6,585
Intangible assets	34,648	9,979
Net deferred loan costs		9,082
Right of use assets	27,012	19,465
Prepaid expense	1,950	474
Tax deductible goodwill	1,302	810
Mortgage servicing rights	6,134	6,688
Other	1,534	480
Total deferred tax liabilities	103,932	55,936
Net deferred tax assets before valuation allowance	116,581	35,203
Less, valuation allowance	(5,635)	(3,887)
Net deferred tax assets	$ 110,946	$ 31,316

Income Taxes - Additional infor

Income Taxes - Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
Provisional income tax expense	$ 26,600
Benefit of tax loss carryback under CARES Act	(31,468)
Change in valuation allowance relating to operating loss carryforwards	3,200
Combined impact of expense (Benefit)	48,800
Unrecognized tax benefits	0
Accrued interest and penalties	0
CSFL
Income Taxes
Provisional income tax expense	119,100
Federal
Income Taxes
Operating loss carryforwards	91,900	$ 31,500
Federal | CSFL
Income Taxes
Operating loss carryforwards	62,900
Annual limitation on operating loss carryforwards	16,000
Valuation allowance relating to operating loss carryforwards	20,700
State
Income Taxes
Operating loss carryforwards	222,900	$ 108,600
Valuation allowance relating to operating loss carryforwards	$ 7,100

Other Expense (Details)

Other Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Expense
Business development and staff related	$ 8,721	$ 8,837	$ 9,536
Bankcard expense	2,224	2,331	1,783
Other loan expense	5,105	2,087	2,028
Director and shareholder expense	4,175	1,859	2,065
Armored carrier and courier expense	2,449	1,874	2,102
Property and sales tax	3,936	2,131	1,760
Low income housing tax credit partnership amortization	12,977	6,141	3,829
Donation	2,121	999	960
Other	11,137	5,234	5,312
Total other noninterest expense	$ 52,845	$ 31,493	$ 29,375

Earnings Per Common Share - Com

Earnings Per Common Share - Computation of basic and diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Basic earnings per common share:
Net income	$ 120,632	$ 186,483	$ 178,871
Weighted-average basic common shares	54,756	34,561	36,530
Basic earnings per common share (in dollars per share)	$ 2.20	$ 5.40	$ 4.90
Diluted earnings per share:
Net income	$ 120,632	$ 186,483	$ 178,871
Weighted-average basic common shares	54,756	34,561	36,530
Effect of dilutive securities (in shares)	307	236	246
Weighted-average dilutive shares	55,063	34,797	36,776
Diluted earnings per common share (in dollars per share)	$ 2.19	$ 5.36	$ 4.86

Earnings Per Common Share - Cal

Earnings Per Common Share - Calculation of diluted EPS under Treasury method (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share
Number of shares	136,844	62,235	62,235
Range of exercise prices, low end of range (in dollars per share)	$ 61.42	$ 87.30	$ 87.30
Range of exercise prices, high end of range (in dollars per share)	$ 91.35	$ 91.35	$ 91.35

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) - Changes in components of AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss)
Balance at the beginning of the period	$ 1,017
Other comprehensive income (loss), net of tax	46,572	$ 25,898	$ (11,507)
Balance at the end of the period	47,589	1,017
Benefit Plans
Accumulated Other Comprehensive Income (Loss)
Balance at the beginning of the period	(149)	(6,450)	(5,998)
Other comprehensive income (loss) before reclassifications	(119)	20	382
Amounts reclassified from accumulated other comprehensive income	117	6,281	926
Other comprehensive income (loss), net of tax	(2)	6,301	1,308
AOCI reclassification to retained earnings from adoption of ASU 2018-02			(1,760)
Balance at the end of the period	(151)	(149)	(6,450)
Unrealized Gains and Losses on Securities Available for Sale
Accumulated Other Comprehensive Income (Loss)
Balance at the beginning of the period	11,922	(18,394)	(4,278)
Other comprehensive income (loss) before reclassifications	35,857	28,245	(13,479)
Amounts reclassified from accumulated other comprehensive income	(39)	2,071	510
Other comprehensive income (loss), net of tax	35,818	30,316	(12,969)
AOCI reclassification to retained earnings from adoption of ASU 2018-02			(1,147)
Balance at the end of the period	47,740	11,922	(18,394)
Gains and Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss)
Balance at the beginning of the period	(10,756)	(37)	(151)
Other comprehensive income (loss) before reclassifications	(26,140)	(10,447)	33
Amounts reclassified from accumulated other comprehensive income	36,896	(272)	121
Other comprehensive income (loss), net of tax	10,756	(10,719)	154
AOCI reclassification to retained earnings from adoption of ASU 2018-02			(40)
Balance at the end of the period		(10,756)	(37)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss)
Balance at the beginning of the period	1,017	(24,881)	(10,427)
Other comprehensive income (loss) before reclassifications	9,598	17,818	(13,064)
Amounts reclassified from accumulated other comprehensive income	36,974	8,080	1,557
Other comprehensive income (loss), net of tax	46,572	25,898	(11,507)
AOCI reclassification to retained earnings from adoption of ASU 2018-02			(2,947)
Balance at the end of the period	$ 47,589	$ 1,017	$ (24,881)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Loss) - Reclassifications out of AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reclassifications out of accumulated other comprehensive income, net of tax
Interest expense	$ (83,564)	$ (86,552)	$ (53,992)
Other-than-temporary impairment losses	0		991
Provision for income taxes	16,660	(43,942)	(45,384)
Net income	120,632	186,483	178,871
Amount Reclassified from Accumulated Other Comprehensive Loss
Reclassifications out of accumulated other comprehensive income, net of tax
Net income	36,974	8,080	1,557
Gains and Losses on Cash Flow Hedges | Amount Reclassified from Accumulated Other Comprehensive Loss | Interest rate contracts
Reclassifications out of accumulated other comprehensive income, net of tax
Interest expense	47,303	(349)	155
Provision for income taxes	(10,407)	77	(34)
Net income	36,896	(272)	121
Unrealized Gains and Losses on Securities Available for Sale | Amount Reclassified from Accumulated Other Comprehensive Loss
Reclassifications out of accumulated other comprehensive income, net of tax
Securities (gains) losses, net	(50)	2,655	655
Provision for income taxes	11	(584)	(145)
Net income	(39)	2,071	510
Benefit Plans | Amount Reclassified from Accumulated Other Comprehensive Loss
Reclassifications out of accumulated other comprehensive income, net of tax
Salaries and employee benefits /Pension Plan Termination Expense	152	8,053	1,187
Provision for income taxes	(35)	(1,772)	(261)
Net income	$ 117	$ 6,281	$ 926

Restrictions on Subsidiary Di_2

Restrictions on Subsidiary Dividends, Loans, or Advances (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2020	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019
Cost of shares repurchased				$ 7,716	$ 2,486	$ 2,173
Special dividend for general operating liquidity				32,000
Amount available for special dividend distribution with approval from SCBFI					157,000		$ 60,000
Maximum amount available for transfer in the form of loans or advances				479,500	246,400
Covid 19
Special dividend for general operating liquidity	$ 33,000
Announced stock repurchase program
Amount available for special dividend distribution without approval from SCBFI	24,700	$ 66,600				$ 66,600
Cost of shares repurchased	$ 24,700	$ 68,400	$ 68,400	$ 24,700	$ 156,900

Retirement Plans - Additional I

Retirement Plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Pension plan termination expense	$ 9,500		$ 9,526
Recognition of pre-tax losses from pension plan		$ 7,700
Write-off of pension plan asset		1,800
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Net loss		$ 0	$ 0
Non-contributory defined benefit pension plan | Employees hired on or before December 31, 2005
Defined Benefit Plan Disclosure [Line Items]
Requisite age of employees for receiving retirement benefits under the plan		21 years
Requisite age of employees for receiving retirement benefits under the new benefit formula		1 year

Retirement Plans - Pension Plan

Retirement Plans - Pension Plan Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Change in benefit obligation:
Benefit obligation at beginning of year	$ 0
Benefit obligation at end of year	$ 0	$ 0
Non-contributory defined benefit pension plan
Change in benefit obligation:
Benefit obligation at beginning of year		28,906	$ 31,500
Service cost		121	77
Interest cost		1,158	1,080
Actuarial (gain) loss		2,471	(2,442)
Expenses		318	121
Plan termination settlements		(31,800)
Benefit obligation at end of year			28,906
Change in plan assets:
Fair value of plan assets at beginning of year		30,545	31,387
Actual return on plan assets		2,111	467
Benefits paid		(538)	(1,188)
Expenses		318	121
Plan termination settlements		$ (31,800)
Fair value of plan assets at end of year			30,545
Funded (unfunded) status			$ 1,639

Retirement Plans - Components O

Retirement Plans - Components Of Net Periodic Pension Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Net periodic pension expense		$ (309)
Other Comprehensive Income
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Interest cost	$ 1,157	1,079
Service cost	121	78
Expected return on plan assets	(2,361)	(2,328)
Recognized net actuarial loss	483	775
Net periodic pension expense	(600)	(396)
Plan termination settlements	10,126
Net periodic pension cost with settlement	9,526
Net (gain) loss	2,722	(581)
Amortization of gain (loss)	(483)	(775)
Plan termination settlement adjustment	(10,126)
Total amount recognized in other comprehensive income	(7,887)	(1,356)
Total recognized in net periodic benefit cost and other comprehensive income	$ 1,639	$ (1,752)

Retirement Plans - Measurement

Retirement Plans - Measurement Date (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Weighted-average assumptions used to determine net periodic pension cost
Discount rate (as a percent)		4.10%	3.50%
Defined Benefit Plan, Benefit Obligation	$ 0	$ 0
Non-contributory defined benefit pension plan
Weighted-average assumptions used to determine net periodic pension cost
Discount rate (as a percent)		4.10%	3.50%
Expected long-term return on plan assets (as a percent)		7.75%	7.75%
Defined Benefit Plan, Benefit Obligation			$ 28,906	$ 31,500
Number of shares repurchased	0	0	0

Retirement Plans - Rate and sta

Retirement Plans - Rate and standard deviation assumptions (Details) - Non-contributory defined benefit pension plan	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Rate of Return Assumption (as a percent)	7.75%	7.75%
Cash equivalents
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Actual asset allocation (as a percent)	2.00%
Cash equivalents | Maximum
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Allowable allocation percentages			35.00%
Cash equivalents | Minimum
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Allowable allocation percentages			0.00%
Equities | Maximum
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Allowable allocation percentages			65.00%
Equities | Minimum
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Allowable allocation percentages			55.00%
Fixed income
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Actual asset allocation (as a percent)	98.00%
Fixed income | Maximum
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Allowable allocation percentages			40.00%
Fixed income | Minimum
Long-term rate of return and standard deviation assumptions used in developing long-term rate of return assumption for the pension plan
Allowable allocation percentages			20.00%

Retirement Plans - Expenses Inc

Retirement Plans - Expenses Incurred And Charged Against Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Pension			$ (309)
Pension plan termination expense		$ 9,526
Employee savings plan/ 401(k)	$ 10,962	6,659	7,948
Supplemental executive retirement plan	2,862	2,343	368
Post-retirement benefits	43	144	254
Non-contributory defined benefit pension plan
Defined Benefit Plan Disclosure [Line Items]
Expenses incurred and charged against operations	$ 13,867	$ 18,672	$ 8,261

Retirement Plans - Safe Harbor

Retirement Plans - Safe Harbor plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Employees' savings plan
Matching contribution by the company (as a percent)	100.00%
Expenses recognized under 401(K) plan	$ 10,962	$ 6,659	$ 7,948
Minimum
Employees' savings plan
Age of employees to be eligible to participate in the defined contribution plan	18 years
Percentage of annual base compensation that participants may elect to contribute	1.00%
Maximum
Employees' savings plan
Percentage of annual base compensation that participants may elect to contribute	50.00%
Percentage of employees salary for which the company contributes a matching contribution	4.00%
Discretionary matching contribution (as a percent)			2.00%

Post-Retirement Benefits (Detai

Post-Retirement Benefits (Details)	12 Months Ended
	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Post-Retirement Benefits
Number of post-retirement health and life insurance benefit plans | item	2
Change in benefit obligation:
Benefit obligation at beginning of year	$ 0
Benefit obligation at end of year	0	$ 0
Weighted-average assumptions used to determine net periodic pension cost
Discount rate (as a percent)		4.10%	3.50%
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Net periodic pension expense			$ (309,000)
Other Comprehensive Income
Change in benefit obligation:
Interest cost		$ 1,157,000	1,079,000
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Interest cost		1,157,000	1,079,000
Recognized net actuarial loss		483,000	775,000
Net periodic pension expense		(600,000)	(396,000)
Net loss		2,722,000	(581,000)
Amortization of gain (loss)		(483,000)	(775,000)
Total amount recognized in other comprehensive income		(7,887,000)	(1,356,000)
Total recognized in net periodic benefit cost and other comprehensive income		1,639,000	(1,752,000)
SCBT Post-retirement Benefit Plan
Change in benefit obligation:
Benefit obligation at beginning of year	254,000	309,000	337,000
Interest cost	6,000	11,000	11,000
Actuarial (gain) loss	(19,000)	(33,000)	2,000
Benefits paid	(32,000)	(33,000)	(41,000)
Benefit obligation at end of year	209,000	254,000	309,000
Change in plan assets:
Employer contribution	32,000	33,000	41,000
Benefits paid	(32,000)	(33,000)	(41,000)
Funded (unfunded) status	$ (209,000)	$ (254,000)	$ (309,000)
Weighted-average assumptions used to determine the benefit obligation
Discount rate (as a percent)	1.60%	2.70%	3.80%
Weighted-average assumptions used to determine net periodic pension cost
Discount rate (as a percent)	2.70%	3.80%	3.20%
Assumed health care cost trend rates
Health care cost trend rate assumed for next fiscal year (as a percent)	5.00%	5.00%	5.00%
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Interest cost	$ 6,000	$ 11,000	$ 11,000
Estimated net loss for the retiree medical plan that will be amortized from other comprehensive income into periodic benefit cost over the next fiscal year
Estimated net loss for the plan that will be amortized from other comprehensive income into periodic benefit cost over the next fiscal year	0
Effects of one-percentage point change in assumed health care cost trend rates
One-Percentage Point Increase, Effect on aggregate service and interest cost	1,000
One-Percentage Point Decrease, Effect on aggregate service and interest cost	(1,000)
One-Percentage Point Increase, Effect on postretirement benefit obligation	10,000
One-Percentage Point Decrease, Effect on postretirement benefit obligation	(10,000)
Estimated future benefit payments (including expected future service as appropriate)
2021	27,000
2022	25,000
2023	24,000
2024	22,000
2025	20,000
2026-2030	71,000
Estimated future benefit payments	189,000
Expected contributions in the next fiscal year
Amount of expected contributions in the next fiscal year	27,000
SCBT Post-retirement Benefit Plan | Other Comprehensive Income
Change in benefit obligation:
Interest cost	6,000	11,000	10,000
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Interest cost	6,000	11,000	10,000
Recognized net actuarial loss	2,000	6,000	6,000
Net periodic pension expense	8,000	17,000	16,000
Net loss	(19,000)	(33,000)	2,000
Amortization of gain (loss)	(2,000)	(6,000)	(6,000)
Total amount recognized in other comprehensive income	(21,000)	(39,000)	(4,000)
Total recognized in net periodic benefit cost and other comprehensive income	(13,000)	(22,000)	12,000
FFCH Post-retirement Benefit Plan
Change in benefit obligation:
Benefit obligation at beginning of year	2,109,000	2,281,000	2,392,000
Interest cost	54,000	82,000	73,000
Actuarial (gain) loss	180,000	7,000	89,000
Benefits paid	(285,000)	(273,000)	(286,000)
less: federal subsidy on benefits paid	12,000	12,000	13,000
Benefit obligation at end of year	2,070,000	2,109,000	2,281,000
Change in plan assets:
Employer contribution	273,000	261,000	286,000
Participants' contributions	12,000	12,000
Benefits paid	(285,000)	(273,000)	(286,000)
Funded (unfunded) status	$ (2,070,000)	$ (2,109,000)	$ (2,281,000)
Weighted-average assumptions used to determine the benefit obligation
Discount rate (as a percent)	1.60%	2.70%	3.80%
Weighted-average assumptions used to determine net periodic pension cost
Discount rate (as a percent)	2.70%	3.80%	3.20%
Assumed health care cost trend rates
Health care cost trend rate assumed for next fiscal year (as a percent)	5.00%	5.00%	5.00%
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Interest cost	$ 54,000	$ 82,000	$ 73,000
Estimated net loss for the retiree medical plan that will be amortized from other comprehensive income into periodic benefit cost over the next fiscal year
Estimated net loss for the plan that will be amortized from other comprehensive income into periodic benefit cost over the next fiscal year	174,000
Effects of one-percentage point change in assumed health care cost trend rates
One-Percentage Point Increase, Effect on aggregate service and interest cost	4,000
One-Percentage Point Decrease, Effect on aggregate service and interest cost	(3,000)
One-Percentage Point Increase, Effect on postretirement benefit obligation	125
One-Percentage Point Decrease, Effect on postretirement benefit obligation	(114)
Estimated future benefit payments (including expected future service as appropriate)
2021	243,000
2022	229,000
2023	213,000
2024	198,000
2025	181,000
2026-2030	671,000
Estimated future benefit payments	1,735,000
Expected contributions in the next fiscal year
Amount of expected contributions in the next fiscal year	243,000
FFCH Post-retirement Benefit Plan | Other Comprehensive Income
Change in benefit obligation:
Interest cost	54,000	82,000	73,000
Components of net periodic pension cost and other amounts recognized in other comprehensive income
Interest cost	54,000	82,000	73,000
Recognized net actuarial loss	151,000	160,000	154,000
Net periodic pension expense	205,000	242,000	227,000
Net loss	180,000	7,000	89,000
Amortization of gain (loss)	151,000	160,000	154,000
Total amount recognized in other comprehensive income	29,000	(153,000)	(65,000)
Total recognized in net periodic benefit cost and other comprehensive income	$ 234,000	$ 89,000	$ 162,000

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended			192 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Number of shares
Exercisable at the end of the period (in shares)		131,216		131,216
Stock Options
Number of shares
Outstanding at the beginning of the period (in shares)	176,888	213,866	218,689
Granted (in shares)			34,407
Assumed stock options and warrants from CSFL merger (in shares)	136,831
Exercised (in shares)	(52,331)	(36,978)	(33,424)
Forfeited (in shares)	(4,963)		(5,806)
Outstanding at the end of the period (in shares)	256,425	176,888	213,866	176,888
Exercisable at the end of the period (in shares)	256,425	131,216	140,115	131,216
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 67.14	$ 61.28	$ 52.75
Granted (in dollars per share)			91.05
Assumed stock options and warrants from CSFL merger (in dollars per share)	37.85
Exercised (in dollars per share)	32.12	33.26	30.88
Forfeited (in dollars per share)	48.89		91.35
Outstanding at the end of the period (in dollars per share)	59.01	67.14	61.28	$ 67.14
Exercisable at the end of the period (in dollars per share)	$ 59.01	$ 60.12	49.41	$ 60.12
Weighted-average fair value of options granted during the year (in dollars per share)			$ 28.01
Aggregate Intrinsic Value
Outstanding at the end of the period	$ 4.6	$ 3.7	$ 1.9	$ 3.7
Exercisable at the end of the period	4.6	3.6	1.9	$ 3.6
Exercised at the end of the period	$ 2	$ 1.4	$ 2
Incentive stock options | Maximum
Share-Based Compensation
Vesting period	4 years
Restricted Stock
Number of shares
Assumed stock options and warrants from CSFL merger (in shares)	9,755
Weighted-Average Exercise Price
Assumed stock options and warrants from CSFL merger (in dollars per share)	$ 60.27
Restricted Stock | Maximum
Share-Based Compensation
Vesting period	12 months
Restricted Stock | Minimum | Employees
Share-Based Compensation
Vesting period	4 years
2012 plan
Share-Based Compensation
Options granted (in shares)	0
2019 plan
Share-Based Compensation
Options granted (in shares)	0
2020 plan
Share-Based Compensation
Number of shares registered	2,072,245
2004 plan
Number of shares
Granted (in shares)				0
Plan 2004 And 2012 | Incentive stock options
Share-Based Compensation
Vesting percentage	25.00%
Expiration period	10 years

Share-Based Compensation - Info

Share-Based Compensation - Information pertaining to options outstanding (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation
Range of exercise prices, low end of range (in dollars per share)	$ 61.42	$ 87.30	$ 87.30
Range of exercise prices, high end of range (in dollars per share)	$ 91.35	$ 91.35	$ 91.35
Options Outstanding
Number outstanding (in shares)	256,425
Weighted Average Remaining Contractual Life	4 years 6 months
Weighted Average Exercise Price (in dollars per share)	$ 59.01
Options Exercisable
Number outstanding (in shares)	256,425
Weighted Average Exercise Price (in dollars per share)	$ 59.01
Weighted Average Remaining Contractual Life	4 years 6 months
Restricted Stock
Vesting schedule of shares
2021	7,935
2022	751
2023	751
2024	1,567
Total	11,004	69,450
19.16 To 40.00
Share Based Compensation
Range of exercise prices, low end of range (in dollars per share)	$ 19.16
Range of exercise prices, high end of range (in dollars per share)	$ 40
Options Outstanding
Number outstanding (in shares)	45,002
Weighted Average Remaining Contractual Life	3 years 1 month 6 days
Weighted Average Exercise Price (in dollars per share)	$ 31.11
Options Exercisable
Number outstanding (in shares)	45,002
Weighted Average Exercise Price (in dollars per share)	$ 31.11
Weighted Average Remaining Contractual Life	3 years 1 month 6 days
40.01 To 55.00
Share Based Compensation
Range of exercise prices, low end of range (in dollars per share)	$ 40.01
Range of exercise prices, high end of range (in dollars per share)	$ 55
Options Outstanding
Number outstanding (in shares)	74,579
Weighted Average Remaining Contractual Life	7 years 8 months 12 days
Weighted Average Exercise Price (in dollars per share)	$ 44.46
Options Exercisable
Number outstanding (in shares)	74,579
Weighted Average Exercise Price (in dollars per share)	$ 44.46
Weighted Average Remaining Contractual Life	7 years 8 months 12 days
55.01 To 70.00
Share Based Compensation
Range of exercise prices, low end of range (in dollars per share)	$ 55.01
Range of exercise prices, high end of range (in dollars per share)	$ 70
Options Outstanding
Number outstanding (in shares)	74,609
Weighted Average Remaining Contractual Life	4 years 1 month 6 days
Weighted Average Exercise Price (in dollars per share)	$ 63.61
Options Exercisable
Number outstanding (in shares)	74,609
Weighted Average Exercise Price (in dollars per share)	$ 63.61
Weighted Average Remaining Contractual Life	4 years 1 month 6 days
70.01 To 85.00
Share Based Compensation
Range of exercise prices, low end of range (in dollars per share)	$ 70.01
Range of exercise prices, high end of range (in dollars per share)	85
85.01 To 91.35
Share Based Compensation
Range of exercise prices, low end of range (in dollars per share)	85.01
Range of exercise prices, high end of range (in dollars per share)	$ 91.35
Options Outstanding
Number outstanding (in shares)	62,235
Weighted Average Remaining Contractual Life	6 years 7 months 6 days
Weighted Average Exercise Price (in dollars per share)	$ 91.12
Options Exercisable
Number outstanding (in shares)	62,235
Weighted Average Exercise Price (in dollars per share)	$ 91.12
Weighted Average Remaining Contractual Life	6 years 7 months 6 days

Share-Based Compensation - Weig

Share-Based Compensation - Weighted average assumptions used in valuing options (Details) - USD ($)	Jun. 07, 2020	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2009	Oct. 29, 2020
Employee Stock Purchase Plan
Additional disclosures
Compensation expense			$ 81,000	$ 75,000	$ 82,000
Employee Stock Purchase Plan
Number of shares of common stock registered in connection with the establishment of an Employee Stock Purchase Plan			363,825				1,400,000
Requisite age of employees to be eligible to participate in the plan			21 years
Requisite service period to be eligible to participate in the plan			6 months
Discount rate for eligible employees to purchase company stock (as a percent)			5.00%			15.00%
Minimum | Employee Stock Purchase Plan
Employee Stock Purchase Plan
Shares available for issuance under the plan			1,400,000
Maximum | Employee Stock Purchase Plan
Employee Stock Purchase Plan
Estimated subscription date fair value (as a percent)			95.00%
Stock Options
Weighted-average assumptions
Dividend yield (as a percent)					1.46%
Expected life					8 years 6 months
Expected volatility (as a percent)					28.00%
Risk-free interest rate (as a percent)					2.54%
Additional disclosures
Total unrecognized compensation cost related to non vested stock option grants			$ 0
Total fair value of shares vested during the period			1,400,000	799,000	$ 700,000
Compensation expense			$ 720,000	641,000	751,000
Restricted Stock Activity and RSUs
Assumed restricted stock shares from CSFL merger (in shares)			136,831
Weighted-Average Grant-Date Fair Value
Assumed restricted stock shares from CSFL merger (in dollars per share)			$ 37.85
Stock Options | CSFL
Additional disclosures
Vesting of stock options		$ 481,000
Restricted Stock
Share-Based Compensation
Options vested (in shares)			61,123
Additional disclosures
Weighted-average period over which unrecognized compensation cost is expected to be recognized			1 year 7 months 9 days
Compensation expense			$ 1,500,000	$ 1,700,000	$ 2,500,000
Options vested (in shares)			61,123
Vesting period hold			2 years
Restricted Stock Activity and RSUs
Nonvested at the beginning of the period (in shares)			69,450
Assumed restricted stock shares from CSFL merger (in shares)			9,755
Granted (in shares)			9,145	8,934	7,836
Vested (in shares)			(77,029)
Forfeited (in shares)			(317)
Nonvested at the end of the period (in shares)			11,004	69,450
Weighted-Average Grant-Date Fair Value
Nonvested at the beginning of the period (in dollars per share)			$ 58.96
Assumed restricted stock shares from CSFL merger (in dollars per share)			60.27
Granted (in dollars per share)			55.96	$ 73.34	$ 87.37
Vested (in dollars per share)			58.67
Forfeited (in dollars per share)			65.86
Nonvested at the end of the period (in dollars per share)			$ 59.42	$ 58.96
Additional disclosures
Total unrecognized compensation cost related to nonvested restricted stock and RSUs granted			$ 537,000,000
Total fair value of shares vested during the period			4,600,000	$ 3,000,000	$ 2,500,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 4,600,000	3,000,000	2,500,000
Restricted Stock | Maximum
Additional disclosures
Vesting period			12 months
Restricted Stock | Employees | Minimum
Additional disclosures
Vesting period			4 years
Restricted Stock | CSFL
Additional disclosures
Vesting of stock options		704,000
Restricted Stock Activity and RSUs
Vested (in shares)	(29,303)
Restricted Stock Units
Additional disclosures
Weighted-average period over which unrecognized compensation cost is expected to be recognized			2 years 9 months 18 days
Compensation expense			$ 21,000,000	$ 6,400,000	$ 5,500,000
Vesting period			3 years
Restricted Stock Activity and RSUs
Nonvested at the beginning of the period (in shares)			324,601
Assumed restricted stock shares from CSFL merger (in shares)			388,381
Granted (in shares)			382,205	159,521	113,270
Vested (in shares)			(275,661)
Forfeited (in shares)			(68,705)
Nonvested at the end of the period (in shares)			750,821	324,601
Weighted-Average Grant-Date Fair Value
Nonvested at the beginning of the period (in dollars per share)			$ 76.44
Assumed restricted stock shares from CSFL merger (in dollars per share)			60.27
Granted (in dollars per share)			61.27
Vested (in dollars per share)			75.63
Forfeited (in dollars per share)			74.09
Nonvested at the end of the period (in dollars per share)			$ 60.88	$ 76.44
Additional disclosures
Total unrecognized compensation cost related to nonvested restricted stock and RSUs granted			$ 27,700,000
Total fair value of shares vested during the period			$ 23,600,000	$ 5,800,000	$ 5,700,000
Target RSU award level (as a percent)			1.00%
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 23,600,000	$ 5,800,000	$ 5,700,000
Restricted Stock Units | CSFL
Additional disclosures
Vesting of stock options		$ 7,500,000
Restricted Stock Activity and RSUs
Vested (in shares)	(242,018)
Performance based restricted stock units
Additional disclosures
Performance period			3 years
Other Performance based restricted stock units
Additional disclosures
Performance period			1 year
Timed based restricted stock units
Additional disclosures
Performance period			4 years

Stock Repurchase Program (Detai

Stock Repurchase Program (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2020	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019	Jan. 31, 2019	Mar. 31, 2017	Feb. 29, 2004
Stock repurchase program
Stock Repurchased During Period, Value				$ 7,716	$ 2,486	$ 2,173
CSFL
Stock repurchase program
Stock Repurchased During Period, Shares				86,263
Stock Repurchased During Period, Value				$ 5,200
Announced stock repurchase program
Stock repurchase program
Shares authorized under repurchase program										250,000
Stock Repurchased During Period, Shares				320,000	2,165,000
Average price per share				$ 77.23	$ 72.49
Stock Repurchased During Period, Value	$ 24,700	$ 68,400	$ 68,400	$ 24,700	$ 156,900
Other stock repurchase arrangements
Stock repurchase program
Stock Repurchased During Period, Shares				122,708	35,674	25,251
Stock Repurchased During Period, Value				$ 7,700	$ 2,500	$ 2,200
2019 Stock Repurchase Program
Stock repurchase program
Shares authorized under repurchase program							2,000,000	1,000,000
Stock Repurchased During Period, Shares				1,485,000
Average price per share							$ 75.26
Number of shares expired				515,000
2004 plan
Stock repurchase program
Shares authorized under repurchase program									1,000,000

Lease Commitments (Details)

Lease Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Right to use asset	$ 113,400	$ 87,400
Lease Liability	$ 118,321	$ 88,800
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other Liabilities	Other Liabilities
Existence of option to extend	true
Renewal term	25 years
ASU 2016- 02 | Adjustment for ASU
Right to use asset			$ 82,200
Lease Liability			$ 82,200

Lease Commitments - Lease cost

Lease Commitments - Lease cost and other information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lease Cost Components:
Amortization of ROU assets - finance leases	$ 289
Interest on lease liabilities - finance leases	44
Operating lease cost (cost resulting from lease payments)	14,266	$ 8,804
Short-term lease expense	404	494
Variable lease cost (cost excluded from lease payments)	1,081	430
Total lease cost	16,084	9,728
Supplemental Cash Flow and Other Information Related to Leases:
Finance lease - operating cash flows	42
Finance lease - financing cash flows	255
Operating lease - operating cash flows (fixed payments)	12,876	7,725
Operating lease - operating cash flows (net change asset/liability)	(9,123)	1,457
New ROU assets - operating leases	43,583	$ 10,239
New ROU assets - finance leases	$ 5,374
Weighted - average remaining lease term (years) - finance leases	7 years 4 months 24 days
Weighted - average remaining lease term (years) - Operating leases	11 years 6 months 3 days	14 years 1 month 20 days
Weighted - average discount rate - finance leases	1.70%
Weighted - average discount rate - Operating leases	3.30%	3.90%
Maturity Analysis of Lease Liabilities:
2021	$ 15,753
2022	14,508
2023	13,482
2024	12,212
2025	10,747
Thereafter	78,711
Total undiscounted cash flows	145,413
Discount on cash flows	(27,092)
Total operating lease liabilities	$ 118,321	$ 88,800

Lease Commitments - Leases not

Lease Commitments - Leases not yet commenced (Details) $ in Millions	Dec. 31, 2020USD ($)
Additional operating leases that not yet commenced	$ 3.5
Maximum
Lease term	10 years

Contingent Liabilities (Details

Contingent Liabilities (Details)	Dec. 31, 2020item
Contingent Liabilities
Number of pending or threatened litigation	0

Related Party Transactions (Det

Related Party Transactions (Details) - South State Bank (the Bank) - Directors and executive officers, their immediate families and their business interests - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Related Party Transactions
Loans outstanding	$ 28.7	$ 37.5
Additional loans made	12.4
Repayments received	17.7
Related party deposits	18.8	$ 21.8
CSFL
Related Party Transactions
Additional loans made	31.8
Loans reduced	$ 35.3

Financial Instruments with Of_3

Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Financial instruments, whose contract amounts represent credit risk
Liability recorded for expected credit losses on unfunded commitments		$ 6,400
Other Liabilities
Financial instruments, whose contract amounts represent credit risk
Liability recorded for expected credit losses on unfunded commitments	$ 43,400
Standby letters of credit
Financial instruments, whose contract amounts represent credit risk
Expiration period of standby letters of credit	1 year
South State Bank (the Bank)
Financial instruments, whose contract amounts represent credit risk
Off balance sheet financial instruments	$ 6,006,352		$ 2,934,869
South State Bank (the Bank) | Commitments to extend credit
Financial instruments, whose contract amounts represent credit risk
Off balance sheet financial instruments	5,929,845		2,902,000
South State Bank (the Bank) | Standby letters of credit and financial guarantees
Financial instruments, whose contract amounts represent credit risk
Off balance sheet financial instruments	$ 76,507		$ 32,869

Fair Value - Assets and liabili

Fair Value - Assets and liabilities measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jul. 07, 2020
Assets
Derivative financial instruments	$ 802,800	$ 15,300
Trading securities			$ 10,674
Securities available for sale	3,330,672	1,956,047
Liabilities
Derivative financial instruments	802,700	16,500
Changes in fair value of assets
Transfers of assets between Level 2 to Level 1	0	0
Transfers of liabilities between Level 1 to Level 2	0	0
Transfers of liabilities between Level 2 to Level 1	0	0
Government-sponsored entities debt
Assets
Securities available for sale	29,256	25,941
State and municipal obligations
Assets
Securities available for sale	520,039	208,415
Corporate securities.
Assets
Securities available for sale	13,702
Significant Other Observable Inputs (Level 2)
Assets
Loans held for sale	290,467	59,363
Trading securities	10,674
Significant Unobservable Inputs (Level 3)
Assets
Mortgage servicing rights	43,820	30,525
Changes in fair value of assets
Changes in hierarchy classifications of Level 3 assets	0
Changes in hierarchy classifications of Level 3 liabilities	0
Recurring basis
Assets
Derivative financial instruments	813,899	16,252
Loans held for sale	290,467	59,363
Trading securities	10,674
Securities available for sale	3,330,672	1,956,047
Mortgage servicing rights	43,820	30,525
Fair value of Assets, Total	4,489,532	2,062,187
Liabilities
Derivative financial instruments	804,832	31,273
Changes in fair value of assets
Transfers of assets between Level 1 to Level 2	0	0
Recurring basis | Government-sponsored entities debt
Assets
Securities available for sale	29,256	25,941
Recurring basis | State and municipal obligations
Assets
Securities available for sale	520,039	208,415
Recurring basis | Mortgage-backed securities
Assets
Securities available for sale	2,767,675	1,721,691
Recurring basis | Corporate securities.
Assets
Securities available for sale	13,702
Recurring basis | Significant Other Observable Inputs (Level 2)
Assets
Derivative financial instruments	813,899	16,252
Loans held for sale	290,467	59,363
Trading securities	10,674
Securities available for sale	3,330,672	1,956,047
Fair value of Assets, Total	4,445,712	2,031,662
Liabilities
Derivative financial instruments	804,832	31,273
Recurring basis | Significant Other Observable Inputs (Level 2) | Government-sponsored entities debt
Assets
Securities available for sale	29,256	25,941
Recurring basis | Significant Other Observable Inputs (Level 2) | State and municipal obligations
Assets
Securities available for sale	520,039	208,415
Recurring basis | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities
Assets
Securities available for sale	2,767,675	1,721,691
Recurring basis | Significant Other Observable Inputs (Level 2) | Corporate securities.
Assets
Securities available for sale	13,702
Recurring basis | Significant Unobservable Inputs (Level 3)
Assets
Mortgage servicing rights	43,820	30,525
Fair value of Assets, Total	43,820	30,525
Changes in fair value of assets
Fair value of assets at the beginning of the period	30,525	34,727
Servicing assets that resulted from transfers of financial assets	28,456	7,363
Changes in fair value assets due to valuation inputs or assumptions	(6,991)	(6,976)
Changes in fair value due to decay	(8,170)	(4,589)
Fair value of assets at the end of the period	43,820	30,525
Unrealized losses included in accumulated other comprehensive income related to Level 3 financial assets and liabilities	$ 0	$ 0

Fair Value - Assets and liabi_2

Fair Value - Assets and liabilities measured at fair value on a nonrecurring basis (Details) - Nonrecurring basis $ in Thousands	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)item
OREO | Fair Value
Fair Value
Other Real Estate	$ 11,914	$ 6,539
Bank property held for sale | Fair Value
Fair Value
Bank property held for sale	36,006	5,425
Non-acquired impaired loans | Fair Value
Fair Value
Other Real Estate	$ 17,609	$ 15,444
Significant Unobservable Inputs (Level 3) | Impaired loans
Quantitative Information about Level 3 Fair Value Measurements
Long-term Debt, Valuation Technique [Extensible List]	us-gaap:MarketApproachValuationTechniqueMember	us-gaap:MarketApproachValuationTechniqueMember
Long-term Debt, Measurement Input [Extensible List]	us-gaap:MeasurementInputDiscountRateMember	us-gaap:MeasurementInputDiscountRateMember
Significant Unobservable Inputs (Level 3) | Impaired loans | Weighted average
Quantitative Information about Level 3 Fair Value Measurements
Discount rate (as a percent) | item	0.05	0.02
Significant Unobservable Inputs (Level 3) | OREO
Fair Value
Other Real Estate	$ 11,914	$ 6,539
Quantitative Information about Level 3 Fair Value Measurements
Long-term Debt, Valuation Technique [Extensible List]	us-gaap:MarketApproachValuationTechniqueMember	us-gaap:MarketApproachValuationTechniqueMember
Long-term Debt, Measurement Input [Extensible List]	us-gaap:MeasurementInputCostToSellMember	us-gaap:MeasurementInputCostToSellMember
Significant Unobservable Inputs (Level 3) | OREO | Weighted average
Quantitative Information about Level 3 Fair Value Measurements
Discount rate (as a percent) | item	0.14	0.31
Significant Unobservable Inputs (Level 3) | Bank property held for sale
Fair Value
Bank property held for sale	$ 36,006	$ 5,425
Significant Unobservable Inputs (Level 3) | Non-acquired impaired loans
Fair Value
Other Real Estate	$ 17,609	$ 15,444

Fair Value - Estimated fair val

Fair Value - Estimated fair value and related carrying amount, of the Company's financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jul. 07, 2020	Dec. 31, 2019
Financial assets:
Trading securities		$ 10,674
Financial liabilities:
Other borrowings	$ 390,179		$ 700,103
Other derivative financial instruments (Mortgage banking related)	804,832		31,273
Carrying Amount
Financial assets:
Cash and cash equivalents	4,609,255		688,704
Trading securities	10,674
Investment securities	4,446,657		2,005,171
Loans held for sale	290,467		59,363
Loans, net of allowance for loan losses	24,206,825		11,313,113
Accrued interest receivable	107,601		36,774
Mortgage servicing rights	43,820		30,525
Interest rate swap - non-designated hedge	802,763		15,350
Other derivative financial instruments (mortgage banking related)	11,136		902
Financial liabilities:
Deposits	30,693,882		12,177,096
Federal funds purchased and securities sold under agreements to repurchase	779,666		298,741
Other borrowings	390,179		815,936
Accrued interest payable	7,103		4,916
Interest rate swap - non-designated hedge	804,832		16,693
Interest rate swap - cash flow hedge			13,791
Other derivative financial instruments (Mortgage banking related)			789
Fair Value
Financial assets:
Cash and cash equivalents	4,609,255		688,704
Trading securities	10,674
Investment securities	4,448,300		2,005,171
Loans held for sale	290,467		59,363
Loans, net of allowance for loan losses	24,757,859		11,452,003
Accrued interest receivable	107,601		36,774
Mortgage servicing rights	43,820		30,525
Interest rate swap - non-designated hedge	802,763		15,350
Other derivative financial instruments (mortgage banking related)	11,136		902
Financial liabilities:
Deposits	30,719,416		11,406,477
Federal funds purchased and securities sold under agreements to repurchase	779,666		298,741
Other borrowings	386,126		818,210
Accrued interest payable	7,103		4,916
Interest rate swap - non-designated hedge	804,832		16,693
Interest rate swap - cash flow hedge			13,791
Other derivative financial instruments (Mortgage banking related)			789
Commitments to extend credit | Fair Value
Financial liabilities:
Commitments to extend credit	136,726		36,031
Quoted Prices In Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and cash equivalents	4,609,255		688,704
Investment securities	160,443		49,124
Significant Other Observable Inputs (Level 2)
Financial assets:
Trading securities	10,674
Investment securities	4,287,857		1,956,047
Loans held for sale	290,467		59,363
Accrued interest receivable	12,952		8,500
Interest rate swap - non-designated hedge	802,763		15,350
Other derivative financial instruments (mortgage banking related)	11,136		902
Financial liabilities:
Deposits	30,719,416		11,406,477
Federal funds purchased and securities sold under agreements to repurchase	779,666		298,741
Other borrowings	386,126		818,210
Accrued interest payable	7,103		4,916
Interest rate swap - non-designated hedge	804,832		16,693
Interest rate swap - cash flow hedge			13,791
Other derivative financial instruments (Mortgage banking related)			789
Significant Other Observable Inputs (Level 2) | Commitments to extend credit
Financial liabilities:
Commitments to extend credit	136,726		36,031
Significant Unobservable Inputs (Level 3)
Financial assets:
Loans, net of allowance for loan losses	24,757,859		11,452,003
Accrued interest receivable	94,649		28,274
Mortgage servicing rights	$ 43,820		$ 30,525

Regulatory Matters (Details)

Regulatory Matters (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Jan. 01, 2019
Capital ratios
Capital conversion buffer common equity Tier 1 of risk-weighted assets (as a percent)				2.50%
Risk-weighted assets ratio	6
Tier One Risk Based Capital to Risk Weighted Assets	11.77		12.25
Capital to Risk Weighted Assets (as a percent)	14.24		12.78
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	8		8
Additional allowance for credit losses for loans	$ 457,309	$ 54,400	$ 56,927
Deferred tax assets	110,946		31,316
Additional reserve for unfunded commitments		6,400
Retained earnings	657,451		679,895
Common equity Tier 1 to risk-weighted assets
Actual, Capital Amount	$ 3,010,174		$ 1,326,725
Actual, Ratio (as a percent)	11.77%		11.30%
Minimum capital required, Ratio (as a percent)	4.50%
Required to be considered well capitalized, Capital Amount	$ 1,662,128		$ 763,495
Required to be considered well capitalized, Ratio (as a percent)	6.50%		6.50%
Tier I capital to risk-weighted assets
Actual, Capital Amount	$ 3,010,174		$ 1,438,995
Actual, Ratio (as a percent)	11.77		12.25
Minimum capital required, Ratio (as a percent)	4
Required to be considered well capitalized, Capital Amount	$ 2,045,696		$ 939,686
Required to be considered well capitalized, Ratio (as a percent)	8		8
Total capital to risk-weighted assets
Actual, Capital Amount	$ 3,642,039		$ 1,501,321
Actual, Ratio (as a percent)	14.24		12.78
Minimum capital required, Ratio (as a percent)	8
Required to be considered well capitalized, Capital Amount	$ 2,557,120		$ 1,174,607
Required to be considered well capitalized, Ratio (as a percent)	10		10
Tier I capital to average assets (leverage ratio)
Actual, Capital Amount	$ 3,010,174		$ 1,438,995
Actual, Ratio (as a percent)	8.27		9.73
Required to be considered well capitalized, Capital Amount	$ 1,818,919		$ 739,664
Required to be considered well capitalized, Ratio (as a percent)	5		5
ASU 2016-13
Capital ratios
Additional allowance for credit losses for loans		54,438
Deferred tax assets		12,639
Additional reserve for unfunded commitments		6,400
Retained earnings	$ 44,800	$ (44,820)
Fully Phased-In
Common equity Tier 1 to risk-weighted assets
Minimum capital required, Capital Amount	$ 1,789,984		$ 822,225
Minimum capital required, Ratio (as a percent)	7.00%		7.00%
Tier I capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 2,173,552		$ 998,416
Minimum capital required, Ratio (as a percent)	8.50		8.50
Total capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 2,684,976		$ 1,233,338
Minimum capital required, Ratio (as a percent)	10.50		10.50
Tier I capital to average assets (leverage ratio)
Minimum capital required, Capital Amount	$ 1,455,135		$ 591,731
Minimum capital required, Ratio (as a percent)	4		4
South State Bank (the Bank)
Capital ratios
Tier One Risk Based Capital to Risk Weighted Assets	12.39		12.07
Capital to Risk Weighted Assets (as a percent)	13.33		12.60
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	8		8
Common equity Tier 1 to risk-weighted assets
Actual, Capital Amount	$ 3,157,098		$ 1,417,616
Actual, Ratio (as a percent)	12.39%		12.07%
Required to be considered well capitalized, Capital Amount	$ 1,656,683		$ 763,488
Required to be considered well capitalized, Ratio (as a percent)	6.50%		6.50%
Tier I capital to risk-weighted assets
Actual, Capital Amount	$ 3,157,098		$ 1,417,616
Actual, Ratio (as a percent)	12.39		12.07
Required to be considered well capitalized, Capital Amount	$ 2,038,994		$ 939,677
Required to be considered well capitalized, Ratio (as a percent)	8		8
Total capital to risk-weighted assets
Actual, Capital Amount	$ 3,397,463		$ 1,479,942
Actual, Ratio (as a percent)	13.33		12.60
Required to be considered well capitalized, Capital Amount	$ 2,548,743		$ 1,174,597
Required to be considered well capitalized, Ratio (as a percent)	10		10
Tier I capital to average assets (leverage ratio)
Actual, Capital Amount	$ 3,157,098		$ 1,417,616
Actual, Ratio (as a percent)	8.71		9.59
Required to be considered well capitalized, Capital Amount	$ 1,813,250		$ 739,490
Required to be considered well capitalized, Ratio (as a percent)	5		5
South State Bank (the Bank) | Fully Phased-In
Common equity Tier 1 to risk-weighted assets
Minimum capital required, Capital Amount	$ 1,784,120		$ 822,218
Minimum capital required, Ratio (as a percent)	7.00%		7.00%
Tier I capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 2,166,432		$ 998,407
Minimum capital required, Ratio (as a percent)	8.50		8.50
Total capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 2,676,180		$ 1,233,327
Minimum capital required, Ratio (as a percent)	10.50		10.50
Tier I capital to average assets (leverage ratio)
Minimum capital required, Capital Amount	$ 1,450,600		$ 591,592
Minimum capital required, Ratio (as a percent)	4		4

Condensed Financial Statement_3

Condensed Financial Statements of Parent Company - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets:
Other Assets	$ 344,269	$ 160,869
Total assets	37,789,873	15,921,881
Corporate and subordinated debentures	390,179	115,833
Other Liabilities	430,054	225,487
Shareholders' equity	4,647,880	2,373,013	$ 2,366,296	$ 2,308,920
Total liabilities and shareholders' equity	37,789,873	15,921,881
Parent company | Reportable Legal Entities
Assets:
Cash	131,522	21,688
Investment in subsidiaries	4,802,993	2,467,466
Other Assets	108,086	204
Total assets	5,042,601	2,482,982
Corporate and subordinated debentures	390,179	115,833
Other Liabilities	4,542	512
Shareholders' equity	4,647,880	2,373,013
Total liabilities and shareholders' equity	$ 5,042,601	$ 2,482,982

Condensed Financial Statement_4

Condensed Financial Statements of Parent Company - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income:
Income before provision for income taxes	$ 103,972	$ 230,425	$ 224,255
Applicable income tax benefit	16,660	(43,942)	(45,384)
Net income	120,632	186,483	178,871
Parent company | Reportable Legal Entities
Income:
Dividends from subsidiary	90,404	214,852	117,298
Operating income	52	5,386	67
Total income	90,456	220,238	117,365
Operating expenses	45,574	15,409	15,302
Income before provision for income taxes	44,882	204,829	102,063
Applicable income tax benefit	8,960	1,883	3,055
Equity in undistributed earnings of subsidiary (excess distribution)	66,790	(20,229)	73,753
Net income	$ 120,632	$ 186,483	$ 178,871

Condensed Financial Statement_5

Condensed Financial Statements of Parent Company - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net income	$ 120,632	$ 186,483	$ 178,871
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	46,367	33,121	35,696
Share-based compensation	23,318	8,839	8,783
Gain on sale of securities available for sale	(50)	(2,711)	655
Decrease (increase) in other assets	27,365	(29,932)	8,962
Decrease in other liabilities	74,079	9,959	(1,186)
Net cash provided by operating activities	536,943	181,028	283,711
Cash flows from investing activities:
Net cash inflow from acquisitions	2,566,376
Net cash provided by (used in) investing activities	1,229,778	(795,053)	(282,149)
Cash flows from financing activities:
Common stock issuance	1,537	1,394	1,331
Common stock repurchased	(32,431)	(159,431)	(70,577)
Dividends paid on common stock	(98,256)	(57,696)	(50,557)
Stock options exercised	1,681	1,230	1,032
Net cash provided by financing activities	2,153,830	893,746	29,794
Net increase in cash and cash equivalents	3,920,551	279,721	31,356
Cash and cash equivalents at beginning of period	688,704	408,983	377,627
Cash and cash equivalents at end of period	4,609,255	688,704	408,983
Parent company | Reportable Legal Entities
Cash flows from operating activities:
Net income	120,632	186,483	178,871
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,528	666	666
Share-based compensation	23,316	8,839	8,783
Gain on sale of securities available for sale		(5,366)
Decrease (increase) in other assets	(11,710)	(159)	1,465
Decrease in other liabilities	(12,323)	(959)	(2,048)
Undistributed earnings of subsidiary	(66,790)	20,229	(73,753)
Net cash provided by operating activities	54,653	209,733	113,984
Cash flows from investing activities:
Proceeds from sales and calls of other investment securities		5,366
Repayment of investments in and advances to subsidiary	163,000
Net cash inflow from acquisitions	19,650
Net cash provided by (used in) investing activities	182,650	5,366
Cash flows from financing activities:
Common stock issuance	1,537	1,394	1,331
Common stock repurchased	(32,431)	(159,431)	(70,577)
Dividends paid on common stock	(98,256)	(57,696)	(50,557)
Stock options exercised	1,681	1,230	1,032
Net cash provided by financing activities	(127,469)	(214,503)	(118,771)
Net increase in cash and cash equivalents	109,834	596	(4,787)
Cash and cash equivalents at beginning of period	21,688	21,092	25,879
Cash and cash equivalents at end of period	$ 131,522	$ 21,688	$ 21,092

Derivative Financial Instrume_3

Derivative Financial Instruments (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019	Mar. 31, 2019
Derivative Financial Instruments
Notional Amount	$ 19,342,657,000	$ 2,051,663,000
Outstanding advances	0	700,000,000
Estimated Fair Value Gain	813,899,000	16,252,000
Estimated Fair Value Loss	804,832,000	31,273,000
Gains (losses) on cash flow hedge in other comprehensive income	10,800,000	(10,700,000)
Cash flow hedge liability	0	13,800,000
Cash flow hedge assets	30,300,000
Ineffectiveness in the cash flow hedge	0	0
Gain or loss recorded	0	0
Interest Rate Derivative Assets, at Fair Value	802,800,000	15,300,000
Interest Rate Derivative Liabilities, at Fair Value	802,700,000	16,500,000
Interest Rate Derivatives, at Fair Value, Net	17,000	1,100,000
Estimated gain (loss) on fair value of open contracts related to mortgage servicing rights	119,000	(789,000)
Termination value of obligations under agreement	38,800,000
Interest expense	83,564,000	86,552,000	$ 53,992,000
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Fair value of forward commitments	(804,832,000)	(31,273,000)
Mortgage loan pipeline
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	510,730,000	80,785,000
Expected closures
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	411,273,000	60,588,000
Cash flow hedge
Derivative Financial Instruments
Collateral provided	0
Cash flow hedge | Borrower
Derivative Financial Instruments
Collateral provided	663,500,000
Cash flow hedge | FHLB Advances - One
Derivative Financial Instruments
Outstanding advances					$ 350,000,000
Cash flow hedge | FHLB Advances - Two
Derivative Financial Instruments
Outstanding advances					150,000,000
Cash flow hedge | FHLB Advances - Three
Derivative Financial Instruments
Notional Amount				$ 200,000,000
Interest rate contracts
Derivative Financial Instruments
Notional Amount	18,600,000,000	1,100,000,000
Mortgage servicing rights hedging | Non-designated hedges
Derivative Financial Instruments
Notional Amount	149,000,000	133,000,000
Mortgage servicing rights hedging | Non-designated hedges | Other Assets and Other Liabilities
Derivative Financial Instruments
Notional Amount	149,000,000	133,000,000
Estimated Fair Value Gain	119,000
Estimated Fair Value Loss		789,000
Mortgage loan pipeline commitments hedging
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	15,328,000	1,160,000
Mortgage loan pipeline commitments hedging | Non-designated hedges | Other Assets
Derivative Financial Instruments
Notional Amount	528,500,000	87,773,000
Estimated Fair Value Gain	11,017,000	902,000
Forward commitments
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	528,500,000	87,773,000
Fair value of forward commitments	4,311,000	258,000
Customer swaps | Cash flow hedge | Investment securities - available for sale
Derivative Financial Instruments
Collateral provided	554,700,000
Interest rate swap
Derivative Financial Instruments
Termination cost	40,800,000
Interest expense	2,000,000
Interest rate swap | Cash flow hedge | FHLB Advances | Other Liabilities | Counterparty
Derivative Financial Instruments
Notional Amount		700,000,000
Estimated Fair Value Loss		13,791,000
Interest rate swap | Cash flow hedge | FHLB Advances - One
Derivative Financial Instruments
Notional Amount					350,000,000
Interest rate swap | Cash flow hedge | FHLB Advances - Two
Derivative Financial Instruments
Notional Amount					$ 150,000,000
Interest rate swap | Cash flow hedge | FHLB Advances - Three
Derivative Financial Instruments
Notional Amount				$ 200,000,000
Interest rate swap | Fair Value Hedging | Counterparty
Derivative Financial Instruments
Notional Amount	16,400,000	2,800,000
Interest rate swap | Fair Value Hedging | Other Assets and Other Liabilities | Counterparty
Derivative Financial Instruments
Notional Amount	16,439,000	2,754,000
Estimated Fair Value Loss	2,086,000	199,000
Interest rate swap | Non-designated hedges | Other Assets and Other Liabilities | Borrower
Derivative Financial Instruments
Notional Amount	9,324,359,000	564,068,000
Estimated Fair Value Gain	802,717,000	15,277,000
Estimated Fair Value Loss	46,000	1,019,000
Interest rate swap | Non-designated hedges | Other Assets and Other Liabilities | Counterparty
Derivative Financial Instruments
Notional Amount	9,324,359,000	564,068,000
Estimated Fair Value Gain	46,000	73,000
Estimated Fair Value Loss	802,700,000	15,475,000
Foreign exchange contract
Derivative Financial Instruments
Gain or loss recorded	$ 0	$ 0

Loan Servicing, Mortgage Orig_3

Loan Servicing, Mortgage Origination, and Loans Held for Sale (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
MSRs
Changes in the fair value of MSRs and its offsetting hedge.
Increase (decrease) in fair value of MSRs	$ (7,421)	$ (6,976)	$ 1,861
Decay of MSRs	(8,793)	(4,589)	(4,215)
Gain related to derivatives	10,177	3,967	(953)
Net effect on statements of income	$ (6,037)	$ (7,598)	$ (3,307)
Characteristics and sensitivity analysis of the MSR
Composition of residential loans serviced for others				100.00%	100.00%
Weighted average life (in years)	6 years 1 month 6 days	6 years 6 months 18 days
Constant Prepayment rate (CPR) (as a percent)	12.30%	10.30%
Weighted average discount rate (as a percent)	9.00%	9.40%
Effect on fair value due to change in interest rates:
25 basis point increase				$ 2,744	$ 2,477
50 basis point increase				5,520	4,452
25 basis point decrease				(2,497)	(2,938)
50 basis point decrease				(4,114)	(6,228)
Custodial escrow balances maintained in connection with the loan servicing				$ 26,600	$ 16,500
Fixed-rate mortgage loans
Characteristics and sensitivity analysis of the MSR
Composition of residential loans serviced for others				99.90%	99.80%
Adjustable-rate mortgage loans
Characteristics and sensitivity analysis of the MSR
Composition of residential loans serviced for others				0.10%	0.20%
First Financial Holdings, Inc. ("First Financial")
Loans held for sale, loan servicing and mortgage origination
Residential mortgages serviced for others				$ 5,100,000	$ 3,300,000
Contractually specified servicing fees earned	$ 9,800	$ 7,800
First Financial Holdings, Inc. ("First Financial") | MSRs
Loans held for sale, loan servicing and mortgage origination
Mortgage servicing rights	30,500	30,500		$ 43,800	$ 30,500
Analysis of the activity in the MSRs
Balance at beginning of the period	30,500
Balance at end of period	$ 43,800	$ 30,500

Loan Servicing, Mortgage Orig_4

Loan Servicing, Mortgage Origination, and Loans Held for Sale - Mandatory cash forwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loan sales	$ 3,200	$ 812,300
Loan securitizations and loan sales	$ 2,700,000	$ 660,600
Percentage of loan securitizations and loan sales	85.10%	81.30%
Loans held for sale	$ 290,467	$ 59,363
Residential mortgage loans awaiting sale in secondary market | Minimum
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, settlement period	15 days
Residential mortgage loans awaiting sale in secondary market | Maximum
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, settlement period	45 days

Investments in Qualified Affo_2

Investments in Qualified Affordable Housing Projects (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Investments in Qualified Affordable Housing Projects
Tax credits and other tax benefits	$ 11.2	$ 5.9
Amortization	12.9	6
Carrying value	105.6	76.9
Original investment value	137.1	137.1
Funding obligation	42.7	$ 35.7
Amount repaid	$ 0

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent event - New Repurchase Program shares in Millions	Jan. 27, 2021shares
Subsequent events
Shares authorized under repurchase program	3.5
Repurchase program, term	2 years