First Financial Bancorp. (FFBC) 10-K 19 Feb 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 18, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-34762
Entity Registrant Name	FIRST FINANCIAL BANCORP.
Entity Incorporation, State or Country Code	OH
Entity Tax Identification Number	31-1042001
Entity Address, Address Line One	255 East Fifth Street, Suite 800
Entity Address, City or Town	Cincinnati
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	45202
City Area Code	877
Local Phone Number	322-9530
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	true
Entity Shell Company	false
Entity Public Float			$ 1,334,086,000
Entity Common Stock, Shares Outstanding		97,374,512
Entity Central Index Key	0000708955
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false
Document Information [Line Items]
Title of 12(g) Security	None
NASDAQ/NMS (GLOBAL MARKET) [Member]
Document Information [Line Items]
Title of 12(b) Security	Common stock, No par value
Trading Symbol	FFBC
Security Exchange Name	NASDAQ

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Cash and due from banks	$ 231,054	$ 200,691
Interest-bearing deposits with other banks	20,305	56,948
Investment securities available-for-sale, at fair value (amortized cost $3,330,029 at December 31, 2020 and $2,798,298 at December 31, 2019)	3,424,580	2,852,084
Investment securities held-to-maturity (fair value $136,698 at December 31, 2020 and $142,821 at December 31, 2019)	131,687	142,862
Other investments	133,198	125,020
Loans held for sale	41,103	13,680
Loans and leases
Total loans and leases	9,900,970	9,201,665
Loans and Leases Receivable, Allowance	175,679	57,650
Net loans and leases	9,725,291	9,144,015
Premises and equipment	207,211	214,506
Goodwill	937,771	937,771
Other intangibles	64,552	76,201
Accrued interest and other assets	1,056,382	747,847
Deposits
Interest-bearing demand	2,914,787	2,364,881
Savings	3,680,774	2,960,979
Time	1,872,733	2,240,441
Total interest-bearing deposits	8,468,294	7,566,301
Total assets	15,973,134	14,511,625
Noninterest-bearing	3,763,709	2,643,928
Total deposits	12,232,003	10,210,229
Federal funds purchased and securities sold under agreements to repurchase	166,594	165,181
FHLB short-term borrowings	0	1,151,000
Total short-term borrowings	166,594	1,316,181
Long-term debt	776,202	414,376
Total borrowed funds	942,796	1,730,557
Accrued interest and other liabilities	516,265	323,134
Total liabilities	13,691,064	12,263,920
Shareholders' equity
Common stock - no par value	1,638,947	1,640,771
Retained earnings	720,429	711,249
Accumulated other comprehensive income (loss)	48,664	13,323
Treasury stock, at cost, 6,259,865 shares in 2020 and 5,790,796 shares in 2019	(125,970)	(117,638)
Total shareholders' equity	2,282,070	2,247,705
Total liabilities and shareholders’ equity	15,973,134	14,511,625
Commercial & industrial
Loans and leases
Total loans and leases	3,007,509	2,465,877
Lease financing
Loans and leases
Total loans and leases	72,987	88,364
Construction real estate
Loans and leases
Total loans and leases	636,096	493,182
Commercial real estate
Loans and leases
Total loans and leases	4,307,858	4,194,651
Residential real estate
Loans and leases
Total loans and leases	1,003,086	1,055,949
Home equity
Loans and leases
Total loans and leases	743,099	771,869
Installment
Loans and leases
Total loans and leases	81,850	82,589
Credit card
Loans and leases
Total loans and leases	$ 48,485	$ 49,184

CONSOLIDATED BALANCE SHEETS CON

CONSOLIDATED BALANCE SHEETS CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Investment securities available-for-sale, cost	$ 3,330,029	$ 2,798,298
Investment securities held-to-maturity, market value	$ 136,698	$ 142,821
Common Stock, No Par Value	$ 0	$ 0
Common Stock, Shares Authorized	160,000,000	160,000,000
Common Stock, Shares, Issued	104,281,794	104,281,794
Treasury Stock, Shares	6,259,865	5,790,796

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Intangible assets amortization	$ 11,126	$ 9,671	$ 7,359
Interest income
Loans and leases, including fees	431,657	499,009	447,187
Investment securities
Taxable	73,789	90,168	79,076
Tax-exempt	19,242	17,596	13,428
Total interest on investment securities	93,031	107,764	92,504
Other earning assets	275	805	691
Total interest income	524,963	607,578	540,382
Interest expense
Deposits	41,922	79,032	56,962
Short-term borrowings	6,442	25,235	18,033
Long-term borrowings	20,088	19,057	16,152
Total interest expense	68,452	123,324	91,147
Net interest income	456,511	484,254	449,235
Provision for loan and lease losses	70,796	30,598	14,586
Provision for Other Credit Losses	(237)	(165)	273
Net interest income after provision for credit losses	385,952	453,821	434,376
Noninterest income
Service charges on deposit accounts	29,446	37,939	35,108
Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions	16,531	15,644	15,082
Bankcard income	11,726	18,804	20,245
Client derivative fees	10,313	15,662	7,682
Foreign exchange income	39,377	7,739	0
Net gain from sales of loans	51,176	14,851	6,071
Net gain (loss) on sales/transfers of investment securities	4,563	(406)	(161)
Equity Securities, FV-NI, Unrealized Gain (Loss)	9,045	575	(208)
Other	16,946	20,565	19,563
Total noninterest income	189,123	131,373	103,382
Noninterest expenses
Salaries and employee benefits	236,779	209,061	188,990
Net occupancy	23,266	24,069	24,215
Furniture and equipment	14,968	15,903	14,908
Data processing	27,514	21,881	28,077
Marketing	6,414	6,908	7,598
Communication	3,492	3,267	3,167
Professional services	9,961	11,254	12,272
Gain (Loss) on Extinguishment of Debt	7,257	0	0
State intangible tax	6,058	5,829	4,152
FDIC assessments	5,110	1,973	3,969
Other	38,719	32,516	28,830
Total noninterest expenses	390,664	342,332	323,537
Income before income taxes	184,411	242,862	214,221
Income tax expense	28,601	44,787	41,626
Net income	$ 155,810	$ 198,075	$ 172,595
Earnings per common share
Basic	$ 1.60	$ 2.01	$ 1.95
Diluted	$ 1.59	$ 2	$ 1.93
Average common shares outstanding - basic	97,363,952	98,305,570	88,582,090
Average common shares outstanding - diluted	98,093,098	98,851,471	89,614,205

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 155,810	$ 198,075	$ 172,595
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) on debt securities arising during the period	32,312	51,959	(11,229)
Change in retirement obligation	3,029	4,649	(8,180)
Unrealized gain (loss) on derivatives	0	217	484
Other comprehensive income (loss)	35,341	56,825	(18,925)
Comprehensive income	$ 191,151	$ 254,900	$ 153,670

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Retained earnings	Retained earningsCumulative Effect, Period of Adoption, Adjustment	Accumulated other comprehensive income (loss)	Accumulated other comprehensive income (loss)Cumulative Effect, Period of Adoption, Adjustment	Treasury stock
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ 0			$ 5,093		$ (5,093)
Balances at January 1, 2018 at Dec. 31, 2017	$ 930,664		$ 573,109	$ 491,847		$ (20,390)		$ (113,902)
Balances at January 1, 2018 at Dec. 31, 2017			68,730,731					(6,661,644)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	172,595			172,595
Other comprehensive loss	(18,925)					(18,925)
Cash dividends declared:
Common Stock at $0.78 per share in 2018, $0.90 per share in 2019, and $0.92 per share in 2020	(69,521)			(69,521)
Stock Issued During Period, Shares, Acquisitions			35,551,063
Common stock issued in connection with business combinations	$ 1,043,424		$ 1,043,424
Treasury Stock, Shares, Acquired	0
Stock Options and Warrants Acquired And Converted Pursuant To Acquisition	$ 16,037		16,037
Adjustments to Additional Paid in Capital, Other	0		(1,120)					$ 1,120
Stock Issued During Period, Shares, Other								65,354
Exercise of stock options, net of shares purchased (in shares)								32,941
Exercise of stock options, net of shares purchased	(284)		(282)					$ (566)
Restricted stock awards, net of forfeitures (in shares)								175,841
Restricted stock awards, net of forfeitures	(2,528)		(4,131)					$ 1,603
Share-based compensation expense	6,219		$ 6,219
Ending Balances (in shares) at Dec. 31, 2018			104,281,794					(6,387,508)
Ending Balances at Dec. 31, 2018	2,078,249		$ 1,633,256	600,014		(44,408)		$ (110,613)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		3,542			2,636		$ 906
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	198,075			198,075
Other comprehensive loss	56,825					56,825
Cash dividends declared:
Common Stock at $0.78 per share in 2018, $0.90 per share in 2019, and $0.92 per share in 2020	(89,476)			(89,476)
Stock Issued During Period, Shares, Acquisitions								2,601,823
Common stock issued in connection with business combinations	$ 60,934		13,658					$ 47,276
Treasury Stock, Shares, Acquired	(2,753,272)							(2,753,272)
Treasury Stock, Value, Acquired, Cost Method	$ (66,218)							$ (66,218)
Adjustments to Additional Paid in Capital, Other	0		(7,830)					$ 7,830
Stock Issued During Period, Shares, Other								452,134
Exercise of stock options, net of shares purchased (in shares)								20,424
Exercise of stock options, net of shares purchased	(90)		(264)					$ (354)
Restricted stock awards, net of forfeitures (in shares)								275,603
Restricted stock awards, net of forfeitures	(2,285)		(6,018)					$ 3,733
Share-based compensation expense	7,969		$ 7,969
Ending Balances (in shares) at Dec. 31, 2019			104,281,794					(5,790,796)
Ending Balances at Dec. 31, 2019	2,247,705		$ 1,640,771	711,249		13,323		$ (117,638)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ (56,882)			(56,882)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	155,810			155,810
Other comprehensive loss	35,341					35,341
Cash dividends declared:
Common Stock at $0.78 per share in 2018, $0.90 per share in 2019, and $0.92 per share in 2020	(89,748)			(89,748)
Common stock issued in connection with business combinations	$ 0
Treasury Stock, Shares, Acquired	(880,000)							(880,000)
Treasury Stock, Value, Acquired, Cost Method	$ (16,686)							$ (16,686)
Exercise of stock options, net of shares purchased (in shares)	10,405							10,405
Exercise of stock options, net of shares purchased	$ (72)		(140)					$ (212)
Restricted stock awards, net of forfeitures (in shares)								400,526
Restricted stock awards, net of forfeitures	(1,220)		(9,362)					$ 8,142
Share-based compensation expense	7,678		$ 7,678
Ending Balances (in shares) at Dec. 31, 2020			104,281,794					(6,259,865)
Ending Balances at Dec. 31, 2020	$ 2,282,070		$ 1,638,947	$ 720,429		$ 48,664		$ (125,970)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest					$ 56,900

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
Common Stock, Dividends, Per Share, Declared	$ 0.92	$ 0.90	$ 0.78

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net income	$ 155,810	$ 198,075	$ 172,595
Adjustments to reconcile net income to net cash provided by operating activities
Provision for credit losses	70,559	30,598	14,586
Depreciation and amortization	33,337	28,138	24,171
Stock-based compensation expense	7,678	7,969	6,219
Pension expense (income)	2,484	1,041	859
Net amortization (accretion) on investment securities	21,053	11,430	10,846
Net (gain) loss on sales/transfers of investments securities	(4,563)	406	161
Equity Securities, FV-NI, Unrealized Gain (Loss)	(9,045)	(575)	208
Originations of loans held for sale	(942,207)	(390,578)	(157,771)
Net (gains) losses on sales of loans held for sale	(51,176)	(14,851)	(6,071)
Proceeds from sales of loans held for sale	965,960	396,121	167,374
Deferred income taxes	(8,380)	12,590	6,267
Operating Lease, Expense	7,897	7,324	0
Operating Lease, Payments	(8,196)	(7,335)	0
Life Insurance, Corporate or Bank Owned, Change in Value	1,506	3,748	5,454
Decrease (increase) in interest receivable	(9,697)	2,117	(3,808)
(Decrease) increase in interest payable	(7,431)	1,545	5,207
Decrease (increase) in other assets	(288,857)	(165,902)	35,000
(Decrease) increase in other liabilities	176,168	71,964	(10,043)
Net cash provided by (used in) operating activities	109,888	186,329	260,346
Investing activities
Proceeds from sales of investment securities available-for-sale	122,248	519,136	290,745
Proceeds from calls, paydowns and maturities of securities available-for-sale	904,821	557,034	387,351
Purchases of securities available-for-sale	(1,551,952)	(834,743)	(852,131)
Proceeds from calls, paydowns and maturities of securities held-to-maturity	41,736	18,062	36,671
Purchases of securities held-to-maturity	(30,250)	0	(14,014)
Proceeds from Maturities, Prepayments and Calls of Other Investments	29,526	0	1,052
Purchases of other investment securities	(28,659)	(12,120)	(31,385)
Net decrease (increase) in interest-bearing deposits with other banks	36,643	(19,210)	(3,764)
Net decrease (increase) in loans and leases	(714,594)	(409,557)	(28,577)
Proceeds from Sale of Other Real Estate	2,076	1,453	3,797
Purchases of premises and equipment	(16,466)	(20,934)	(18,228)
Net cash acquired (paid) in business combinations	0	(51,663)
Cash Acquired from Acquisition			64,895
(Payments for) Proceeds from Branch Divestitures	0	(118)	41,197
Net cash provided by (used in) investing activities	(1,204,871)	(252,424)	(204,785)
Financing activities
Net (decrease) increase in total deposits	2,021,774	69,953	(18,690)
Net (decrease) increase in short-term borrowings	(1,149,587)	275,490	30,531
Payments on long-term borrowings	(681,511)	(159,653)	(52,460)
Proceeds from FHLBank Borrowings, Financing Activities	1,040,975	0	150,000
Cash dividends paid on common stock	(89,691)	(89,097)	(79,655)
Treasury stock purchase	(16,686)	(66,218)	0
Proceeds from exercise of stock options	72	90	284
Net cash provided by (used in) financing activities	1,125,346	30,565	30,010
Cash and due from banks
Net (decrease) increase in Cash and due from banks	30,363	(35,530)	85,571
Cash and due from banks at beginning of year	200,691	236,221	150,650
Cash and due from banks at end of year	231,054	200,691	236,221
Supplemental disclosures
Interest paid	75,884	121,779	84,125
Income taxes paid	32,579	27,497	16,004
Acquisition of other real estate owned through foreclosure	1,017	2,448	3,182
Issuance of restricted stock awards	9,370	10,488	8,797
Securities transferred from HTM to AFS	0	268,703	372,128
Common stock issued in bank acquisitions	0	60,934	1,043,424
us-gaap_OperatingLeaseRightOfUseAsset	0	60,249	0
us-gaap_OperatingLeaseLiability	0	65,799	0
Supplemental schedule for investing activities
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Assets, Net Of Purchase Consideration	0	(39,140)	3,342,781
Total liabilities assumed	0	18,380	4,018,948
Goodwill	$ 0	$ 57,520	$ 676,167

RESTRICTIONS ON CASH AND DIVIDE

RESTRICTIONS ON CASH AND DIVIDENDS	12 Months Ended
	Dec. 31, 2020
Subsidiaries [Member]
Restrictions on Subsidiary Dividends, Loans or Advances [Line Items]
Restrictions On Cash And Dividends [Text Block]	Restrictions on Cash and Dividends In 2019, First Financial was required by the FRB to hold cash in reserve against deposit liabilities when total reservable deposit liabilities exceed the regulatory exemption known as the reserve requirement. The reserve requirement was calculated based on a two-week average of daily net transaction account deposits as defined by the FRB and may be satisfied with average vault cash during the following two-week maintenance period. When vault cash was not sufficient to meet the reserve requirement, the remaining amount was satisfied with average funds held at the FRB. First Financial's deposit at the FRB was recorded in Interest-bearing deposits with other banks on the Consolidated Balance Sheets. The average required reserve balances, based upon the average level of First Financial's transaction deposits was $84.1 million for 2019. Effective March 2020, the FRB eliminated reserve requirements for all depository institutions. Therefore, for 2020, First Financial had no required reserves. Additionally, as of December 31, 2020 and 2019, First Financial had $38.0 million and $15.8 million, respectively, in cash restricted for withdrawal and usage due to the centrally cleared derivative initial margin requirement. Dividends paid by First Financial to its shareholders are principally funded through dividends paid to the Company by its subsidiaries; however, certain restrictions exist regarding the ability of the Bank to transfer funds to First Financial in the form of cash dividends, loans or advances. The approval of the Federal Reserve Board and the ODFI is required for the Bank to pay dividends in excess of the regulatory limit, which is equal to the net income of the current year through the dividend date combined with the Bank's retained net income from the two preceding years. As of December 31, 2020, First Financial's subsidiaries had retained earnings of $700.0 million, of which $198.0 million was available for distribution to First Financial without prior regulatory approval.

DEPOSITS

DEPOSITS	12 Months Ended
	Dec. 31, 2020
Deposits [Abstract]
Deposit Liabilities Disclosures [Text Block]	Deposits Time deposits that meet or exceed the FDIC insurance limit of $250,000 at December 31, 2020 and 2019 were $220.5 million and $285.0 million, respectively. Scheduled maturities of all time deposits for the next five years were as follows: (Dollars in thousands) Time deposits 2021 $ 1,544,131 2022 215,855 2023 56,882 2024 32,978 2025 22,210 Thereafter 677 Total $ 1,872,733

FIRST FINANCIAL BANCORP. (PAREN

FIRST FINANCIAL BANCORP. (PARENT COMPANY ONLY) FINANCIAL INFORMATION	12 Months Ended
	Dec. 31, 2020
Condensed Financial Information Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure [Text Block]	First Financial Bancorp. (Parent Company Only) Financial Information Balance Sheets December 31, (Dollars in thousands) 2020 2019 Assets Cash $ 172,902 $ 55,869 Investment securities 1,388 1,116 Subordinated notes from subsidiaries 7,500 7,500 Investment in subsidiaries Commercial bank 2,346,009 2,272,991 Non-banks 9,559 8,260 Total investment in subsidiaries 2,355,568 2,281,251 Premises and equipment 1,328 1,344 Other assets 68,812 77,572 Total assets $ 2,607,498 $ 2,424,652 Liabilities Subordinated notes $ 320,615 $ 171,983 Dividends payable 674 849 Other liabilities 4,139 4,115 Total liabilities 325,428 176,947 Shareholders’ equity 2,282,070 2,247,705 Total liabilities and shareholders’ equity $ 2,607,498 $ 2,424,652 Statements of Income and Comprehensive Income Years Ended December 31, (Dollars in thousands) 2020 2019 2018 Income Interest income $ 27 $ 30 $ 23 Noninterest income 272 191 0 Dividends from subsidiaries 81,725 196,800 107,340 Total income 82,024 197,021 107,363 Expenses Interest expense 14,172 9,552 8,798 Salaries and employee benefits 8,004 8,169 6,413 Professional services 1,160 1,040 5,130 Other 5,163 6,599 5,648 Total expenses 28,499 25,360 25,989 Income before income taxes and equity in undistributed net earnings of subsidiaries 53,525 171,661 81,374 Income tax expense (benefit) (6,145) (5,975) (6,687) Equity in undistributed earnings (loss) of subsidiaries 96,140 20,439 84,534 Net income $ 155,810 $ 198,075 $ 172,595 Comprehensive income $ 191,151 $ 254,900 $ 153,670 Statements of Cash Flows Years Ended December 31, (Dollars in thousands) 2020 2019 2018 Operating activities Net income $ 155,810 $ 198,075 $ 172,595 Adjustments to reconcile net income to net cash provided by operating activities Equity in undistributed (earnings) loss of subsidiaries (96,140) (20,439) (84,534) Depreciation and amortization 712 584 194 Stock-based compensation expense 7,678 7,969 6,219 Deferred income taxes (158) 1,255 739 (Decrease) increase in dividends payable (175) 384 (10,500) (Decrease) increase in other liabilities (22) (244) 9,979 Decrease (increase) in other assets 8,635 (7,187) 16,346 Net cash provided by (used in) operating activities 76,340 180,397 111,038 Investing activities Capital contributions to subsidiaries 0 0 (3,000) Net cash acquired (paid) in business combinations 0 (53,660) 11,353 Proceeds from sales and maturities of investment securities 0 264 0 Purchases of investment securities 0 (500) 0 Net cash (used in) provided by investing activities 0 (53,896) 8,353 Financing activities (Decrease) increase in short-term borrowings 0 0 (8,333) Proceeds from long-term borrowings 150,000 0 0 Cash dividends paid on common stock (89,691) (89,097) (79,655) Purchases of common stock (16,686) (66,218) 0 Proceeds from exercise of stock options, net of shares purchased 72 90 284 Other (3,002) (2,285) (2,528) Net cash provided by (used in) financing activities 40,693 (157,510) (90,232) Net increase (decrease) in cash 117,033 (31,009) 29,159 Cash at beginning of year 55,869 86,878 57,719 Cash at end of year $ 172,902 $ 55,869 $ 86,878

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Notes)	12 Months Ended
	Dec. 31, 2020
Summary of Significant Accounting Policies [Abstract]
BASIS OF PRESENTATION	Summary of Significant Accounting Policies Basis of presentation. The Consolidated Financial Statements of First Financial Bancorp., a financial holding company, principally serving Ohio, Indiana, Kentucky and Illinois, include the accounts and operations of First Financial and its wholly owned subsidiary, First Financial Bank. All significant intercompany transactions and accounts have been eliminated in consolidation. Certain reclassifications of prior years' amounts have been made to conform to current year presentation. Such reclassifications had no effect on net earnings. Use of estimates. The preparation of financial statements in conformity with GAAP requires management to make estimates, assumptions and judgments that affect the amounts reported in the Consolidated Financial Statements and accompanying Notes. These estimates, assumptions and judgments are inherently subjective and my Actual realized amounts could differ materially from those estimates. COVID-19. In the majority of 2020, First Financial's operations and financial results were significantly impacted by the COVID-19 pandemic. The spread of COVID-19 has caused significant economic disruption throughout the United States as state and local governments issued stay at home orders and temporarily closed non-essential businesses. The full financial impact from the pandemic is unknown at this time, however prolonged disruption may adversely impact several industries within the Company's geographic footprint and impair the ability of First Financial's customers to fulfill their contractual obligations to the Company. This could cause First Financial to experience a material adverse effect on business operations, asset valuations, financial condition and results of operations. Material adverse impacts may include all or a combination of valuation impairments on First Financial's intangible assets, investments, loans, mortgage servicing rights or counter-party risk derivatives. Cash and due from banks. Cash and due from banks consist of currency, coin and cash items due from banks. Cash items due from banks include noninterest-bearing balances that are on deposit at other depository institutions. Investment securities. First Financial classifies debt securities into three categories: HTM, trading and AFS. Management classifies investment securities into the appropriate category at the time of purchase and re-evaluates that classification as deemed appropriate. Investment securities are classified as HTM when First Financial has the positive intent and ability to hold the securities to maturity. HTM securities are recorded at amortized cost. Investment securities classified as trading are held principally for resale in the near-term and are recorded at fair value. Fair value is determined using quoted market prices. Gains or losses on trading securities, both realized and unrealized, are reported in noninterest income. Investment securities not classified as either HTM or trading are classified as AFS. AFS securities are recorded at fair value, with the unrealized gains and losses, net of tax, reported as a separate component of accumulated other comprehensive income (loss) in shareholders' equity. The amortized cost of investment securities classified as either HTM or AFS is adjusted for amortization of premiums and accretion of discounts to maturity, or in the case of mortgage-backed securities, over the estimated life of the security. Such amortization and accretion are considered an adjustment to the yield on the security and included in interest income from investments. Interest and dividends are also included in interest income from investment securities in the Consolidated Statements of Income. Realized gains and losses are based on the amortized cost of the security sold using the specific identification method. Other investments. Other investments include holdings in FRB and FHLB stock, which are both carried at cost as well as equity securities, including class B Visa shares which are carried at fair value. Changes in the fair value of equity securities are recorded in Unrealized gain (loss) on securities in the Consolidated Statements of Income. Loans held for sale. Loans held for sale consist of residential real estate loans newly originated for the purpose of sale to third parties, and in certain circumstances, loans previously originated that have been specifically identified by management for sale based on predetermined criteria. Loans held for sale are carried at fair value. Any subsequent change in the carrying value of transferred loans, not to exceed original cost, is recorded in the Consolidated Statements of Income. First Financial sells loans with servicing retained or released depending on pricing and market conditions. Loans and leases. Loans and leases for which First Financial has the intent and ability to hold for the foreseeable future, or until maturity or payoff, are classified in the Consolidated Balance Sheets as loans and leases. Loans and leases are carried at the principal amount outstanding, net of unamortized deferred loan origination fees and costs, and net of unearned income. Loan origination and commitment fees received, as well as certain direct loan origination costs paid, are deferred, and the net amount is amortized as an adjustment to the related loan's yield. Interest income on loans and leases is recorded on an accrual basis. When a loan is classified as nonaccrual, the accrual of interest income is discontinued and previously accrued, but unpaid interest is reversed. Any payments received while a loan is classified as nonaccrual are applied as a reduction to the carrying value of the loan. A loan may return to accrual status if collection of future principal and interest payments is no longer doubtful. Allowance for credit losses - held-to-maturity securities . Management measures expected credit losses on held-to-maturity debt securities on a collective basis by security type. The estimate of expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Management classifies the held-to-maturity portfolio into the following major security types: Mortgage-backed, CMOs and Obligations of state and other political subdivisions. Nearly all of the HTM securities held by the Company are issued by U.S. government entities and agencies. These securities are either explicitly or implicitly guaranteed by the U.S. government, are highly rated by major rating agencies and have a long history of no credit losses. The remainder of the Company's HTM securities are non-agency collateralized mortgage obligations and obligations of state and other political subdivisions which currently carry ratings no lower than A+. Accrued interest receivable on held-to maturity debt securities, which totaled $0.3 million as of December 31, 2020, is excluded by policy election from the estimate of credit losses. Allowance for credit losses - available-for-sale securities. For available-for-sale debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For debt securities available-for-sale that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that has not been recorded through an allowance for credit loss is recognized in other comprehensive income. Changes in the allowance for credit losses are recorded as provision for credit loss expense. Losses are charged against the allowance when management believes the uncollectibility of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. Accrued interest receivable on available-for-sale debt securities, which totaled $12.9 million as of December 31, 2020, is excluded from the estimate of credit losses. Allowance for credit losses - loans and leases. T he allowance for credit losses is a valuation account that is deducted from the loans’ amortized cost basis to present the net amount expected to be collected on the loans. Management's determination of the adequacy of the ACL is based on an assessment of the expected credit losses on loan and leases over the expected life of the loan. The ACL is increased by provision expense and decreased by charge-offs, net of recoveries of amounts previously charged-off. Loans are charged off when management believes that the collection of the princ ipal amount owed in full, either through payments from the borrower or a guarantor or from the liquidation of collateral, is unlikely. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged-off. Any interest that is accrued bu t not collected is reversed against interest income when a loan is placed on nonaccrual status, which typically occurs prior to charging off all, or a portion, of a loan. The Company made the policy election to exclude accrued interest receivable on loans and leases from the estimate of credit losses. Management estimates the allowance balance using relevant available information from both internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience paired with economic forecasts provide the basis for the quantitatively modeled estimation of expected credit losses. First Financial adjusts its quantitative model, as necessary, to reflect conditions not already considered by the quantitative model. These adjustments are commonly known as the Qualitative Framework. First Financial quantitatively models expected credit loss using PD, LGD and EAD over the R&S forecast period, reversion and post-reversion periods. Utilizing third-party software, the Bank forecasts PD by using a parameterized transition matrix approach. Average transition matrices are calculated over the TTC period, which was defined as the period from December 2007 to December 2016. TTC transition matrices are adjusted under forward-looking macroeconomic expectations to obtain R&S forecasts. First Financial is not required to develop forecasts over full the contractual term of the financial asset or group of financial assets. Rather, for periods beyond which the entity is able to make or obtain R&S forecasts of expected credit losses, the Company reverts in a straight line manner over a one year period to an average TTC loss level that is reflective of the prepayment adjusted contractual term of the financial asset or group of financial assets. The R&S period, elected by the bank to be two years, is forecasted using econometric data sourced from Moody's, an industry-leading independent third party. FFB utilizes a non-parametric loss curve approach embedded within a third-party software for estimating LGD. The PD multiplied by LGD produces an expected loss rate that, when calculating the ACL, is applied to contractual loan cash flows, adjusted for expected future rates of principal prepayments. The Company adjusts its quantitative model for certain qualitative factors to reflect the extent to which management expects current conditions and R&S forecasts to differ from the conditions that existed for the period over which historical information was evaluated. The Qualitative Framework reflects changes related to relevant data, such as changes in asset quality trends, portfolio growth and composition, national and local economic factors, credit policy and administration and other factors not considered in the base quantitative model. Loans that do not share risk characteristics are evaluated on an individual basis. First Financial will typically evaluate on an individual basis any loans that are on nonaccrual, designated as a TDR, or reasonably expected to be designated as a TDR. When management determines that foreclosure is probable or when repayment is expected to be provided substantially through the operation or sale of underlying collateral, expected credit losses are based on the fair value of the collateral at the reporting date, adjusted for selling costs. For loans evaluated on an individual basis that are not determined to be collateral dependent, a discounted cash flow analysis is performed to determine expected credit losses. Expected credit losses are estimated over the contractual term of the loans, adjusted for expected prepayments when appropriate. The contractual term excludes expected extensions, renewals and modifications unless either of the following applies: management has a reasonable expectation at the reporting date that a troubled debt restructuring will be executed with an individual borrower or the extension or renewal options are included in the original or modified contract at the reporting date and are not unconditionally cancellable by the Company. Credit card receivables do not have stated maturities. In determining the estimated life of a credit card receivable, management first estimates the future cash flows expected to be received and then applies those expected future cash flows to the credit card balance. Allowance for credit losses - unfunded commitments . Effective January 1, 2020, First Financial adopted ASC 326, at which time First Financial estimated expected credit losses over the contractual period in which the Company is exposed to credit risk via a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by the Company. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on commitments expected to be funded over its estimated life consistent with the Company's ACL methodology for loans and leases. A djustments to the reserve for unfunded commitments are recorded in Provision for credit losses - unfunded commitments in the Consolidated Statements of Income. The reserve for unfunded commitments is included in Accrued interest and other liabilities on the Consolidated Balance Sheets. Prior to the adoption of ASC 326, First Financial maintained its reserve to absorb probable losses incurred in standby letters of credit and outstanding loan commitments. First Financial determined the adequacy of this reserve based upon an evaluation of the unfunded credit facilities, which included consideration of historical commitment utilization experience, credit risk ratings and historical loss rates, consistent with the Company's ALLL methodology at the time. Premises and equipment. Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation and amortization are principally computed on the straight-line method over the estimated useful lives of the assets. Useful lives generally range from 10 to 40 years for building and building improvements; 3 to 10 years for furniture, fixtures and equipment; and 3 to 5 years for software, hardware and data handling equipment. Land improvements are depreciated over 20 years and leasehold improvements are depreciated over the lesser of the term of the respective lease or the useful life of the asset. Premises and equipment are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Maintenance and repairs are expensed as incurred. Bank-owned life insurance. First Financial purchases life insurance policies on the lives of certain employees and is the owner and beneficiary of the policies. The Bank invests in these policies to provide an efficient form of funding for long-term retirement and other employee benefits costs. The policies are included within Accrued interest and other assets in the Consolidated Balance Sheets at each policy’s respective cash surrender value with changes recorded in Other noninterest income in the Consolidated Statements of Income. Goodwill. Under accounting for business combinations, the net assets of entities acquired by First Financial are recorded at their estimated fair value at the date of acquisition. The excess cost of the acquisition over the fair value of net assets acquired is recorded as goodwill. Goodwill and other intangible assets deemed to have indefinite lives are not amortized, but are subject to annual impairment tests. The Company is required to evaluate goodwill for impairment on an annual basis or whenever events or changes in circumstances indicate that the carrying value may not be recoverable. First Financial performs its annual impairment test effective October 1, absent events or changes in circumstances that indicate the carrying value of goodwill may not be recoverable. The Company’s goodwill is accounted for in a single reporting unit representing the consolidated entity. Our quantitative impairment analysis utilized the discounted cash flow model for the income approach and the market multiple methodology and comparable transaction methodology as the market approach. These valuation methodologies utilize key assumptions that include forecasts of revenues and expenses derived from internal management projections for a period of five years, changes in working capital estimates, company specific discount rate derived from a rate build up approach, externally sourced bank peer group market multiples and externally sourced bank peer group change in control premium, all of which are highly subjective and require significant management judgment. Changes in these key assumptions could materially affect our estimate of the reporting unit fair value and could affect our conclusion regarding the existence of potential impairment. Other intangible assets. Other intangible assets consist primarily of core deposit, customer list and other miscellaneous intangibles. CDI represent the estimated value of acquired customer deposit relationships. CDI are recorded at fair value at the date of acquisition and are based on a discounted cash flow methodology that gives appropriate consideration to expected customer attrition rates, cost of the deposit base, reserve requirements and the net maintenance cost attributable to customer deposits. Core deposit intangibles are recorded in Other intangibles on the Consolidated Balance Sheets and are amortized on an accelerated basis over their estimated useful lives. First Financial recorded a customer list intangible asset in conjunction with the Bannockburn merger to account for the obligation or advantage on the part of either the Company or the customer to continue the pre-existing relationship subsequent to the merger. The customer list intangible asset is amortized on a straight-line basis over its estimated useful life. Other miscellaneous intangibles include purchase commissions, non-compete agreements and trade name intangibles. Other intangible assets are included in Other intangibles in the Consolidated Balance Sheets. Other real estate owned. OREO consists of properties acquired by the Company primarily through the loan foreclosure or repossession process, or other resolution activity that results in partial or total satisfaction of problem loans. OREO properties are recorded at fair value, less estimated disposal costs (net realizable value). Losses arising at the time of acquisition of such properties are charged against the ACL. Management performs periodic valuations to assess the adequacy of recorded OREO balances and subsequent changes in the carrying value of OREO properties are recorded in the Consolidated Statements of Income. Improvements to OREO properties may be capitalized if the improvements contribute to the overall value of the property, but may not be capitalized in excess of the net realizable value of the property. When management disposes of an OREO property, any gains or losses realized at the time of disposal are reflected in the Consolidated Statements of Income. Affordable housing projects. First Financial has investments in certain qualified affordable housing projects. These projects are indirect federal subsidies that provide tax incentives to encourage investment in the development, acquisition and rehabilitation of affordable rental housing, and allow investors to claim tax credits and other tax benefits (such as deductions from taxable income for operating losses) on their federal income tax returns. The principal risk associated with qualified affordable housing investments is the potential for noncompliance with the tax code requirements, such as failure to rent properties to qualified tenants, resulting in unavailability or recapture of the tax credits and other tax benefits. Investments in affordable housing projects are included in Accrued interest and other assets in the Consolidated Balance Sheets and are accounted for under the proportional amortization method. Under the proportional amortization method, the initial cost of the investment is amortized in proportion to the tax credits and other benefits received and recognized as a component of Income tax expense in the Consolidated Statements of Income. Investments in historic tax credits. First Financial has noncontrolling financial investments in private investment funds and partnerships which are not consolidated. These investments may generate a return through the realization of federal and state income tax credits, as well as other tax benefits, such as tax deductions from net operating losses of the investments over a period of time. Investments in historic tax credits are accounted for under the equity method of accounting. The Company’s recorded investment in these entities is carried in Accrued interest and other assets on the Consolidated Balance Sheets. For historic tax credits, impairment is recorded in Other noninterest expense. These tax credits and other net tax benefits received are recognized as a component of income tax expense in the Consolidated Statements of Income. Investments in renewable energy credits . First Financial has investments in renewable energy projects where it has noncontrolling interest which is not consolidated. This investment may generate a return through the realization of federal and state income tax credits, as well as other tax benefits, such as tax deductions from net operating losses of the investments over a period of time. Investments in renewable energy tax credits are accounted for under the equity method of accounting and are included in Accrued interest and other assets on the Consolidated Balance Sheets. These tax credits and other net tax benefits received are recognized as a component of income tax expense in the Consolidated Statements of Income. Income taxes. First Financial and its subsidiaries file a consolidated federal income tax return. Each subsidiary provides for income taxes on a separate return basis, and remits to First Financial amounts determined to be currently payable. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Interest and penalties on income tax assessments or income tax refunds are recorded in Other noninterest expense in the Consolidated Statements of Income. Pension. First Financial sponsors a non-contributory defined benefit pension plan covering substantially all employees. The measurement of the accrued benefit liability and the annual pension expense involves actuarial and economic assumptions, which include the discount rate, the expected return on plan assets and the rate of compensation increase. Derivative instruments. First Financial accounts for its derivative financial instruments in accordance with FASB ASC Topic 815, Derivatives and Hedging. FASB ASC Topic 815 requires all derivative instruments to be carried at fair value on the balance sheet. The accounting for changes in the fair value of derivatives is based on the intended use of the derivative and the resulting designation. Derivatives used to hedge the exposure to changes in the fair value of an asset, liability or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivatives used to hedge the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Client derivatives - First Financial utilizes matched interest rate swaps as a means to offer commercial borrowers fixed rate funding while providing the Company with floating rate assets. Upon entering into an interest rate swap with a borrower, the Bank simultaneously enters into an offsetting swap agreement with an institutional counterparty, with substantially matching terms. These matched interest rate swap agreements generally involve the receipt by First Financial of floating rate amounts from the counterparties in exchange for payments to these counterparties by First Financial of fixed rate amounts received from commercial borrowers over the life of the agreements. First Financial's matched interest rate swaps qualify as derivatives, but are not designated as hedging instruments. The net interest receivable or payable on matched interest rate swaps is accrued and recognized as an adjustment to interest income. The fair values of client derivatives are included within Accrued interest and other assets and Accrued interest and other liabilities in the Consolidated Balance Sheets. First Financial may enter into foreign exchange derivative contracts for the benefit of commercial customers to hedge their exposure to foreign currency fluctuations. Similar to the hedging of interest rate risk from interest rate derivative contracts, First Financial also enters into foreign exchange contracts with major financial institutions to economically hedge a substantial portion of the exposure from client driven foreign exchange activity. These derivatives are classified as free-standing instruments with the revaluation gain or loss recorded in Foreign exchange income in the Consolidated Statements of Income. Credit derivatives - In conjunction with participating interests in commercial loans, First Financial periodically enters into risk participation agreements with counterparties whereby First Financial assumes a portion of the credit exposure associated with an interest rate swap on the participated loan in exchange for a fee. Under these agreements, First Financial will make payments to the counterparty if the loan customer defaults on its obligation to perform under the interest rate swap contract with the counterparty. The fair value of these agreements is recorded in the Consolidated Balance Sheets in Accrued interest and other liabilities. Mortgage derivatives - First Financial enters into IRLCs and forward commitments for the future delivery of mortgage loans to third party investors, which are considered derivatives. When borrowers secure an IRLC with First Financial and the loan is intended to be sold, First Financial will enter into forward commitments for the future delivery of the loans to third party investors in order to hedge against the effect of changes in interest rates impacting IRLCs and and Loans held for sale. The fair value of these agreements is recorded in the Consolidated Balance Sheets in Accrued interest and other assets. Stock-based compensation. First Financial grants stock-based awards, including restricted stock awards and options to purchase the Company’s common stock. Stock option grants are for a fixed number of shares to employees and directors with an exercise price equal to the fair value of the shares at the date of grant. Stock-based compensation expense is recognized in the Consolidated Statements of Income on a straight-line basis over the vesting period. As compensation expense is recognized, a deferred tax asset is recorded that represents an estimate of the future tax deduction from exercise. At the time stock-based awards are exercised, canceled or expire, First Financial may be required to recognize an adjustment to tax expense. Earnings per share. Basic earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of shares of common stock outstanding during the period. Diluted earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of common shares outstanding, unvested shares and dilutive common stock equivalents outstanding during the period. Common stock equivalents, which consist of common stock issuable under the assumed exercise of stock options granted under First Financial's stock-based compensation plans and the assumed conversion of common stock warrants, are calculated using the treasury stock method. Segments and related information. While the Company monitors the operating results of its six lines of business, operations are managed and financial performance is evaluated on a consolidated basis. Accordingly, and consistent with prior years, all of the Company's operations are considered by management to be aggregated in one reportable operating segment.

RECENTLY ADOPTED AND ISSUED ACC

RECENTLY ADOPTED AND ISSUED ACCOUNTING STANDARDS	12 Months Ended
	Dec. 31, 2020
Accounting Standards Update and Change in Accounting Principle [Abstract]
RECENTLY ADOPTED AND ISSUED ACCOUNTING STANDARDS	Accounting Standards Recently Adopted or Issued Standards Adopted in 2020 On January 1, 2020, the Company adopted ASU 2016-13 Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which replaces the incurred loss methodology with an expected loss methodology that is referred to as the current expected credit loss (CECL) methodology. The measurement of expected credit losses under the CECL methodology is applicable to financial assets measured at amortized cost, including loan receivables and held-to-maturity debt securities. It also applies to off-balance sheet credit exposures not accounted for as insurance (loan commitments, standby letters of credit, financial guarantees, and other similar instruments) and net investments in leases recognized by a lessor in accordance with Topic 842 on leases. In addition, ASC 326 made changes to the accounting for available-for-sale debt securities. One such change is to require credit losses to be presented as an allowance rather than as a write-down on available-for-sale debt securities management does not intend to sell or believes that it is more likely than not they will be required to sell. The Company adopted ASC 326 using the modified retrospective method for all financial assets measured at amortized cost and off-balance-sheet (OBS) credit exposures. Results for reporting periods beginning after January 1, 2020 are presented under ASC 326 while prior period amounts continue to be reported in accordance with previously applicable GAAP. The Company recorded a net decrease to retained earning s of $56.9 million as of January 1, 2020 for the cumulative effect of adopting ASC 326. As detailed in the following table, the transition adjustment included a $61.5 million increase to the ACL, a $12.2 million increase in the ACL for unfunded commitments and a $16.8 million decrease in Deferred tax liability. The Company adopted CECL using the prospective transition approach for financial assets purchased with credit deterioration that were previously classified as purchased credit impaired and accounted for under ASC 310-30. In accordance with the standard, First Financial did not reassess whether PCI assets met the definition of PCD assets as of the date of adoption. The final rule provides banking organizations the option to phase in over a three-year period the day-one adverse effects on regulatory capital that may result from the adoption of the new accounting standard. In March 2020, the OCC, the Board of Governors of the Federal Reserve System, and the FDIC announced an interim final rule to delay the estimated impact on regulatory capital stemming from the implementation of CECL. The interim final rule maintains the three-year transition option in the previous rule and provides banks the option to delay for two years an estimate of CECL’s effect on regulatory capital, relative to the incurred loss methodology’s effect on regulatory capital, followed by a three-year transition period. First Financial is adopting the capital transition relief over the five year permissible period. The impact of adopting ASC 326 was as follows: January 1, 2020 (dollars in thousands) As Reported under ASC 326 Pre-ASC 326 Impact of ASC 326 Adoption Assets Loans Commercial and industrial $ 28,485 $ 18,584 $ 9,901 Lease financing 1,089 971 118 Construction real estate 13,960 2,381 11,579 Commercial real estate 47,697 23,579 24,118 Residential real estate 10,789 5,299 5,490 Home equity 13,217 4,787 8,430 Installment 1,193 392 801 Credit card 2,725 1,657 1,068 Allowance for credit losses on loans $ 119,155 $ 57,650 $ 61,505 Liabilities Deferred tax liability $ 16,252 $ 33,030 $ (16,778) Allowance for credit losses on OBS credit exposures 12,740 585 12,155 For more information on the calculation of the ACL, please refer to Note 1 - Summary of Significant Accounting Policies and Note 5 - Allowance for Credit Losses. During the first quarter of 2020, the Company adopted ASU No. 2018-13, Disclosure Framework: Changes to the Disclosure Requirements for Fair Value Measurement, which eliminates, adds and modifies certain disclosure requirements for fair value measurements. Under the changes, entities are no longer required to disclose the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy, but must disclose the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. This update did not have a material impact on the Company’s Consolidated Financial Statements. Standards Adopted in 2019 In February 2016, the FASB issued an update (ASU 2016-02, Leases) which requires lessees to record most leases on their balance sheet and recognize leasing expenses in the income statement. Operating leases where the Company is the lessee, except for short-term leases that are subject to an accounting policy election, were recorded on the balance sheet by establishing a lease liability and corresponding ROU asset. All entities are required to use a modified retrospective approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements. As the Company elected the transition option provided in ASU No. 2018-11, the modified retrospective approach was applied on January 1, 2019 (as opposed to January 1, 2017). The Company also elected certain relief options offered in ASU 2016-02 including the package of practical expedients, the option not to separate lease and non-lease components and instead to account for them as a single lease component and the option not to recognize ROU assets and lease liabilities that arise from short-term leases. The Company did not elect the hindsight practical expedient, which allows entities to use hindsight when determining lease term and impairment of ROU assets. The guidance in this ASU became effective January 1, 2019 at which time the Company recorded on the Consolidated Balance Sheet an ROU asset of $60.2 million and a lease liability of $65.8 million. For further detail, see Note 7 – Leases. In March 2017, the FASB issued an update (ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20), Premium Amortization on Purchased Callable Debt Securities) which amends the amortization period for certain purchased callable debt securities held at a premium and shortens the amortization period for the premium to the earliest call date rather than as an adjustment of yield over the contractual life of the instrument. This update more closely aligns the amortization period of premiums and discounts to expectations incorporated in market pricing on the underlying securities, as in most cases, market participants price securities to the call date that produces the worst yield when the coupon is above current market rates (that is, the security is trading at a premium) and price securities to maturity when the coupon is below market rates (that is, the security is trading at a discount) in anticipation that the borrower will act in its economic best interest in an attempt to more closely align interest income recorded on bonds held at a premium or a discount with the economics of the underlying instrument. The guidance in this ASU became effective at the beginning of 2019 but did not have a material impact on the Consolidated Financial Statements. In August 2017, the FASB issued an update (ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities) to better align financial reporting for hedging activities with the economic objectives of those activities. This update aligns certain aspects of hedge documentation, effectiveness assessments, accounting and disclosures and expands permissible hedge strategies as of the date of adoption. The guidance in this ASU became effective January 1, 2019. Upon adoption, the Company reclassified $268.7 million of HTM securities to AFS, resulting in a $0.2 million loss in the Consolidated Statement of Income. Standards Issued But Not Adopted In December 2019, the FASB issued ASU 2019-12 - Income Taxes (Topic 740): Simplifying the Accounting for Income Taxe

INVESTMENTS

INVESTMENTS	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
INVESTMENTS	Investment SecuritiesDuring the year ended December 31, 2020, proceeds on the sale of $117.8 million of AFS securities resulted in gains of $0.9 million and losses of $0.8 million. During the year ended December 31, 2019, proceeds on the sale of $519.1 million of AFS securities resulted in gains of $2.1 million and losses of $2.1 million. During the year ended December 31, 2018, proceeds on the sale of $290.7 million of AFS securities resulted in gains of $0.5 million and losses of $0.6 million. The impact to income tax expense from these sales was insignificant in all three years. In 2020, t here were no reclassifications of HTM securities. However, in the first quarter of 2019, in addition to the sale of certain securities, First Financial reclassified $268.7 million of HTM securities to AFS in conjunction with the adoption of ASU 2017-12, resulting in a $0.2 million realized loss recorded in the Consolidated Statement of Income. D uring the second quarter of 2018, First Financial sold certain securities and reclassified $372.1 million of HTM securities to AFS to align with post-merger investment strategies. The carrying value of investment securities pledged as collateral to secure public deposits, repurchase agreements and for other purposes as required by law totaled $1.5 billion at December 31, 2020 and $1.1 billion at December 31, 2019. The following is a summary of HTM and AFS investment securities as of December 31, 2020: Held-to-maturity Available-for-sale (Dollars in thousands) Amortized Unrecognized Unrecognized Fair Amortized Unrealized Unrealized Fair U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 99 $ 4 $ 0 $ 103 Securities of U.S. government agencies and corporations 0 0 0 0 60 0 0 60 Mortgage-backed securities - residential 13,990 197 0 14,187 704,482 15,938 (237) 720,183 Mortgage-backed securities - commercial 71,737 3,485 0 75,222 584,125 10,395 (3,584) 590,936 Collateralized mortgage obligations 5,799 79 0 5,878 634,418 21,148 (445) 655,121 Obligations of state and other political subdivisions 9,911 1,239 0 11,150 856,054 46,755 (291) 902,518 Asset-backed securities 0 0 0 0 478,539 4,158 (826) 481,871 Other securities 30,250 11 0 30,261 72,252 1,544 (8) 73,788 Total $ 131,687 $ 5,011 $ 0 $ 136,698 $ 3,330,029 $ 99,942 $ (5,391) $ 3,424,580 The following is a summary of HTM and AFS investment securities as of December 31, 2019: Held-to-maturity Available-for-sale (Dollars in thousands) Amortized Unrecognized Unrecognized Fair Amortized Unrealized Unrealized Fair U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 99 $ 1 $ 0 $ 100 Securities of U.S. government agencies and corporations 0 0 0 0 156 2 0 158 Mortgage-backed securities - residential 20,818 122 (174) 20,766 421,945 9,709 (99) 431,555 Mortgage-backed securities - commercial 101,267 571 (1,225) 100,613 474,174 4,988 (2,644) 476,518 Collateralized mortgage obligations 9,763 0 (108) 9,655 769,076 16,753 (385) 785,444 Obligations of state and other political subdivisions 11,014 804 (31) 11,787 652,986 23,729 (462) 676,253 Asset-backed securities 0 0 0 0 400,081 1,414 (1,064) 400,431 Other securities 0 0 0 0 79,781 1,959 (115) 81,625 Total $ 142,862 $ 1,497 $ (1,538) $ 142,821 $ 2,798,298 $ 58,555 $ (4,769) $ 2,852,084 The following table provides a summary of investment securities by contractual maturity as of December 31, 2020, except for residential and commercial mortgage-backed securities, collateralized mortgage obligations and asset-backed securities, which are shown as single totals, due to the unpredictability of the timing in principal repayments: Held-to-maturity Available-for-sale (Dollars in thousands) Amortized Fair Amortized Fair Due in one year or less $ 0 $ 0 $ 5,745 $ 5,802 Due after one year through five years 0 0 62,930 64,886 Due after five years through ten years 36,084 37,205 161,307 169,692 Due after ten years 4,077 4,206 698,483 736,089 Mortgage-backed securities - residential 13,990 14,187 704,482 720,183 Mortgage-backed securities - commercial 71,737 75,222 584,125 590,936 Collateralized mortgage obligations 5,799 5,878 634,418 655,121 Asset-backed securities 0 0 478,539 481,871 Total $ 131,687 $ 136,698 $ 3,330,029 $ 3,424,580 Unrealized gains and losses on debt securities are generally due to fluctuations in current market yields relative to the yields of the debt securities at their amortized cost. All securities with unrealized losses are reviewed quarterly to determine if any impairment exists, requiring a write-down to fair value through income. For securities in an unrealized loss position, the Company first assesses whether it intends to sell or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For debt securities available-for-sale that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security . At this time, First Financial does not intend to sell, and it is not more likely than not that the Company will be required to sell, debt securities temporarily impaired prior to maturity or recovery of the recorded value. The Company recorded no reserves on investment securities for the twelve months ended December 31, 2020. Prior to the adoption of ASC 326, First Financial had no other than temporary impairment related to its investment securities portfolio for the twelve months ended December 31, 2019. As of December 31, 2020, the Company's investment securities portfolio consisted of 1,351 securities, of which 94 were in an unrealized loss position. As of December 31, 2019, the Company's investment securities portfolio consisted of 1,273 securities, of which 140 were in an unrealized loss position. Prior to the adoption of ASC 326, there was no OTTI recorded during the twelve months ended December 31, 2019. Primarily all of First Financial’s HTM debt securities are issued by U.S. government-sponsored enterprises. These securities carry the explicit and/or implicit guarantee of the U.S. government, are widely recognized as “risk free,” and have a long history of zero credit loss. The remainder of the Company's HTM securities are non-agency collateralized mortgage obligations and obligations of state and other political subdivisions which currently carry ratings no lower than A+. There were no HTM securities on nonaccrual status, past due or in a loss position as of December 31, 2020. The Company did not record an allowance for credit losses for these securities as of December 31, 2020. The following tables provide the fair value and gross unrealized losses on investment securities in an unrealized loss position for which an allowance for credit losses was not recorded, aggregated by investment category and the length of time the individual securities have been in a continuous loss position: December 31, 2020 Less than 12 months 12 months or more Total (Dollars in thousands) Fair Unrealized Fair Unrealized Fair Unrealized U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 Securities of U.S. government agencies and corporations 0 0 0 0 0 0 Mortgage-backed securities - residential 57,872 (237) 0 0 57,872 (237) Mortgage-backed securities - commercial 169,825 (986) 48,158 (2,598) 217,983 (3,584) Collateralized mortgage obligations 49,161 (445) 1 0 49,162 (445) Obligations of state and other political subdivisions 60,008 (291) 0 0 60,008 (291) Asset-backed securities 84,749 (435) 68,967 (391) 153,716 (826) Other securities 4,992 (8) 0 0 4,992 (8) Total $ 426,607 $ (2,402) $ 117,126 $ (2,989) $ 543,733 $ (5,391) December 31, 2019 Less than 12 months 12 months or more Total (Dollars in thousands) Fair Unrealized Fair Unrealized Fair Unrealized U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 Securities of U.S. Government agencies and corporations 0 0 0 0 0 0 Mortgage-backed securities - residential 40,190 (209) 11,063 (64) 51,253 (273) Mortgage-backed securities - commercial 111,658 (298) 104,069 (3,571) 215,727 (3,869) Collateralized mortgage obligations 85,248 (297) 30,628 (196) 115,876 (493) Obligations of state and other political subdivisions 118,623 (457) 7,950 (36) 126,573 (493) Asset-backed securities 125,889 (553) 54,963 (511) 180,852 (1,064) Other securities 0 0 5,649 (115) 5,649 (115) Total $ 481,608 $ (1,814) $ 214,322 $ (4,493) $ 695,930 $ (6,307) For further detail on the fair value of investment securities, see Note 22 – Fair Value Disclosures.

LOANS

LOANS	12 Months Ended
	Dec. 31, 2020
Loans [Abstract]
LOANS (excluding covered loans)	Loans and Leases First Financial offers clients a variety of commercial and consumer loan and lease products with various interest rates and payment terms. Commercial loan categories include C&I, CRE, construction real estate and lease financing. Consumer loan categories include residential real estate, home equity, installment and credit card. Lending activities are primarily concentrated in states where the Bank operates banking centers (Ohio, Indiana, Kentucky and Illinois). First Financial also offers two nationwide lending platforms, one that provides equipment and leasehold improvement financing for franchisees in the quick service and casual dining restaurant sector and another that provides loans that are secured by commissions and cash collateral accounts to insurance agents and brokers. In accordance with the CARES Act, First Financial participated in offering PPP loans to its customers. These loans provide a direct incentive for small businesses to keep their workers on the payroll and to maintain their operations. PPP loans are eligible to be forgiven by the government provided certain conditions as outlined in the CARES Act are met. As of December 31, 2020, First Financial had $594.6 million in PPP loans, net of unearned fees of $13.7 million. Credit quality. To facilitate the monitoring of credit quality for commercial loans, First Financial utilizes the following categories of credit grades: Pass - Higher quality loans that do not fit any of the other categories described below. Special Mention - First Financial assigns a special mention rating to loans and leases with 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 lease or in First Financial's credit position at some future date. Substandard - First Financial assigns a substandard rating to loans or leases that are inadequately protected by the current sound financial worth and paying capacity of the borrower or the collateral pledged, if any. Substandard loans and leases have well-defined weaknesses that jeopardize repayment of the debt. Substandard loans and leases are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not addressed. Doubtful - First Financial assigns a doubtful rating to loans and leases with all of the attributes of a substandard rating with the added characteristic that the weaknesses make collection or liquidation in full highly questionable and improbable, on the basis of currently existing facts, conditions and values. The possibility of loss is extremely high, but because of certain important and reasonably specific pending factors that may work to the advantage and strengthening of the credit quality of the loan or lease, its classification as an estimated loss is deferred until its more exact status may be determined. Pending factors include proposed merger, acquisition or liquidation procedures, capital injection, perfecting liens on additional collateral and refinancing plans. The credit grades previously described are derived from standard regulatory rating definitions and are assigned upon initial approval of credit to borrowers and updated periodically thereafter. First Financial considers repayment performance to be the best indicator of credit quality for consumer loans. Consumer loans that have principal and interest payments that are past due by 90 days or more are generally classified as nonperforming. Additionally, consumer loans that have been modified in a TDR are classified as nonperforming. The following table sets forth the Company's loan portfolio at December 31, 2020 by risk attribute and origination date: (Dollars in thousands) 2020 2019 2018 2017 2016 Prior Term Total Revolving Total Commercial & industrial Pass $ 1,141,163 $ 460,210 $ 296,221 $ 208,077 $ 122,686 $ 138,307 $ 2,366,664 $ 502,286 $ 2,868,950 Special mention 24,668 10,281 18,118 6,893 6,668 6,090 72,718 10,470 83,188 Substandard 6,709 2,370 8,022 26,565 5,124 1,192 49,982 5,389 55,371 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 1,172,540 $ 472,861 $ 322,361 $ 241,535 $ 134,478 $ 145,589 $ 2,489,364 $ 518,145 $ 3,007,509 Lease financing Pass $ 22,916 $ 22,397 $ 12,942 $ 6,967 $ 4,802 $ 2,368 $ 72,392 $ 0 $ 72,392 Special mention 290 0 0 0 0 0 290 0 290 Substandard 5 0 0 180 120 0 305 0 305 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 23,211 $ 22,397 $ 12,942 $ 7,147 $ 4,922 $ 2,368 $ 72,987 $ 0 $ 72,987 Construction real estate Pass $ 96,410 $ 259,524 $ 182,625 $ 23,185 $ 24,786 $ 426 $ 586,956 $ 19,671 $ 606,627 Special mention 0 621 18,203 9,984 661 0 29,469 0 29,469 Substandard 0 0 0 0 0 0 0 0 0 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 96,410 $ 260,145 $ 200,828 $ 33,169 $ 25,447 $ 426 $ 616,425 $ 19,671 $ 636,096 Commercial real estate - investor Pass $ 515,950 $ 1,011,898 $ 427,077 $ 378,536 $ 286,587 $ 361,403 $ 2,981,451 $ 56,398 $ 3,037,849 Special mention 0 17,463 15,534 44,426 32,408 43,704 153,535 559 154,094 Substandard 6,198 2,043 22,497 7,067 68 14,724 52,597 0 52,597 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 522,148 $ 1,031,404 $ 465,108 $ 430,029 $ 319,063 $ 419,831 $ 3,187,583 $ 56,957 $ 3,244,540 Commercial real estate - owner Pass $ 185,692 $ 162,480 $ 147,236 $ 125,275 $ 128,755 $ 211,519 $ 960,957 $ 36,721 $ 997,678 Special mention 4,292 11,380 2,891 8,230 3,017 19,384 49,194 59 49,253 Substandard 668 504 7,054 5,496 306 2,321 16,349 38 16,387 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 190,652 $ 174,364 $ 157,181 $ 139,001 $ 132,078 $ 233,224 $ 1,026,500 $ 36,818 $ 1,063,318 Residential real estate Performing $ 290,277 $ 241,601 $ 115,747 $ 64,220 $ 60,094 $ 224,281 $ 996,220 $ 0 $ 996,220 Nonperforming 321 429 673 643 87 4,713 6,866 0 6,866 Total $ 290,598 $ 242,030 $ 116,420 $ 64,863 $ 60,181 $ 228,994 $ 1,003,086 $ 0 $ 1,003,086 Home equity Performing $ 60,967 $ 20,200 $ 17,445 $ 11,308 $ 9,744 $ 41,571 $ 161,235 $ 577,609 $ 738,844 Nonperforming 0 0 0 39 28 138 205 4,050 4,255 Total $ 60,967 $ 20,200 $ 17,445 $ 11,347 $ 9,772 $ 41,709 $ 161,440 $ 581,659 $ 743,099 Installment Performing $ 21,584 $ 15,614 $ 11,041 $ 8,812 $ 1,954 $ 3,185 $ 62,190 $ 19,479 $ 81,669 Nonperforming 15 53 23 35 17 36 179 2 181 Total $ 21,599 $ 15,667 $ 11,064 $ 8,847 $ 1,971 $ 3,221 $ 62,369 $ 19,481 $ 81,850 Credit cards Performing $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 47,845 $ 47,845 Nonperforming 0 0 0 0 0 0 0 640 640 Total $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 48,485 $ 48,485 Grand Total $ 2,378,125 $ 2,239,068 $ 1,303,349 $ 935,938 $ 687,912 $ 1,075,362 $ 8,619,754 $ 1,281,216 $ 9,900,970 Commercial and consumer credit exposure by risk attribute as of December 31, 2019 was as follows: As of December 31, 2019 Real Estate (Dollars in thousands) Commercial & industrial Construction Commercial Lease Total Pass $ 2,324,021 $ 493,182 $ 4,108,752 $ 85,262 $ 7,011,217 Special Mention 100,954 0 59,383 488 160,825 Substandard 40,902 0 26,516 2,614 70,032 Doubtful 0 0 0 0 0 Total $ 2,465,877 $ 493,182 $ 4,194,651 $ 88,364 $ 7,242,074 Residential Home equity Installment Credit card Total Performing $ 1,040,787 $ 766,169 $ 82,385 $ 48,983 $ 1,938,324 Nonperforming 15,162 5,700 204 201 21,267 Total $ 1,055,949 $ 771,869 $ 82,589 $ 49,184 $ 1,959,591 Delinquency. Loans are considered past due or delinquent when the contractual principal or interest due in accordance with the terms of the loan agreement or any portion thereof remains unpaid after the due date of the scheduled payment. Loan delinquency, including nonaccrual loans, was as follows: As of December 31, 2020 (Dollars in thousands) 30 – 59 60 – 89 > 90 days Total Current Total > 90 days Loans Commercial & industrial $ 6,532 $ 0 $ 1,861 $ 8,393 $ 2,999,116 $ 3,007,509 $ 0 Lease financing 0 0 0 0 72,987 72,987 0 Construction real estate 0 0 0 0 636,096 636,096 0 Commercial real estate-investor 136 0 24,422 24,558 3,219,982 3,244,540 0 Commercial real estate-owner 6,480 174 400 7,054 1,056,264 1,063,318 0 Residential real estate 2,809 370 3,687 6,866 996,220 1,003,086 0 Home equity 1,483 835 1,937 4,255 738,844 743,099 0 Installment 94 35 51 180 81,670 81,850 0 Credit card 303 163 174 640 47,845 48,485 169 Total $ 17,837 $ 1,577 $ 32,532 $ 51,946 $ 9,849,024 $ 9,900,970 $ 169 As of December 31, 2019 (Dollars in thousands) 30 - 59 60 - 89 > 90 days Total Current Subtotal Purchased impaired Total > 90 days Loans Commercial & industrial $ 1,266 $ 3,332 $ 14,518 $ 19,116 $ 2,443,680 $ 2,462,796 $ 3,081 $ 2,465,877 $ 0 Lease financing 0 0 0 0 88,364 88,364 0 88,364 0 Construction real estate 0 0 0 0 493,167 493,167 15 493,182 0 Commercial real estate 776 857 5,613 7,246 4,151,513 4,158,759 35,892 4,194,651 0 Residential real estate 8,032 1,928 5,031 14,991 1,014,138 1,029,129 26,820 1,055,949 0 Home equity 2,530 1,083 2,795 6,408 762,863 769,271 2,598 771,869 0 Installment 111 50 148 309 82,022 82,331 258 82,589 0 Credit card 208 75 201 484 48,700 49,184 0 49,184 201 Total $ 12,923 $ 7,325 $ 28,306 $ 48,554 $ 9,084,447 $ 9,133,001 $ 68,664 $ 9,201,665 $ 201 For PCD assets, the delinquency status was determined individually for each loan in accordance with the individual loan's contractual repayment terms. Prior to the adoption of CECL in the first quarter of 2020, PCI loans were classified as performing, even though they may have been contractually past due, as any nonpayment of contractual principal or interest was considered in the periodic re-estimation of expected cash flows and was included in the resulting recognition of current period provision for credit losses or prospective yield adjustments. Nonaccrual. Loans are classified as nonaccrual when, in the opinion of management, collection of principal or interest is doubtful or when principal or interest payments are 90 days or more past due. Generally, loans are classified as nonaccrual due to the continued failure to adhere to contractual payment terms by the borrower, coupled with other pertinent factors. When a loan is classified as nonaccrual, the accrual of interest income is discontinued and previously accrued but unpaid interest is reversed. Any payments received while a loan is on nonaccrual status are applied as a reduction to the carrying value of the loan. A loan classified as nonaccrual may return to accrual status if none of the principal and interest is due and unpaid, and the Bank expects repayment of the remaining contractual principal and interest. Troubled debt restructurings. A loan modification is considered a TDR when the borrower is experiencing financial difficulty and concessions are made by the Company that would not otherwise be considered for a borrower with similar credit characteristics. The most common types of modifications include interest rate reductions, maturity extensions and modifications to principal amortization, including interest-only structures. Modified terms are dependent upon the financial position and needs of the individual borrower. If the modification agreement is violated, the loan is managed by the Company’s credit administration group for resolution, which may result in foreclosure in the case of real estate. In accordance with the CARES Act, performing loans that demonstrated limited signs of credit deterioration, but were modified to provide borrowers relief during the COVID-19 pandemic were not considered to be TDR as of December 31 2020. TDRs are generally classified as nonaccrual for a minimum period of six months and may qualify for return to accrual status once they have demonstrated performance with the restructured terms of the loan agreement. First Financial had 155 TDRs totaling $21.8 million at December 31, 2020, including $7.1 million of loans on accrual status and $14.7 million of loans classified as nonaccrual. First Financial had $0.3 million commitments outstanding to lend additional funds to borrowers whose loan terms had been modified through TDRs, and the ACL included reserves of $8.8 million related to TDRs as of December 31, 2020. For the year ended December 31, 2020, First Financial charged off $1.7 million for the portion of TDRs determined to be uncollectible. Additionally, as of December 31, 2020, approximately $5.0 million of the accruing TDRs have been performing in accordance with the restructured terms for more than one year. First Financial had 157 TDRs totaling $30.0 million at December 31, 2019, including $11.4 million of loans on accrual status and $18.5 million of loans classified as nonaccrual. First Financial had $2.5 million commitments outstanding to lend additional funds to borrowers whose loan terms had been modified through TDRs. At December 31, 2019 the ALLL included reserves of $2.5 million related to TDRs, and $4.7 million of the accruing TDRs had been performing in accordance with the restructured terms for more than one year. Additionally, First Financial charged off $2.6 million for the portion of TDRs determined to be uncollectible for the year ended December 31, 2019. First Financial had 196 TDRs totaling $38.5 million at December 31, 2018, including $16.1 million of loans on accrual status and $22.4 million of loans classified as nonaccrual. First Financial had no commitments outstanding to lend additional funds to borrowers whose loan terms had been modified through TDRs. At December 31, 2018, the ALLL included reserves of $1.5 million related to TDRs, and $7.9 million of the accruing TDRs had been performing in accordance with the restructured terms for more than one year. Additionally, First Financial charged off $0.9 million for the portion of TDRs determined to be uncollectible for the year ended December 31, 2018. The following table provides information on loan modifications classified as TDRs during the years ended December 31, 2020, 2019 and 2018: Years ended December 31, 2020 2019 2018 (Dollars in thousands) Number of loans Pre-modification loan balance Period end balance Number of loans Pre-modification loan balance Period end balance Number of loans Pre-modification loan balance Period end balance Commercial & industrial 8 $ 14,984 $ 14,984 8 $ 25,009 $ 25,071 17 $ 23,943 $ 23,890 Construction 0 0 0 0 0 0 0 0 0 Commercial 0 0 0 9 3,024 2,932 8 3,385 3,150 Residential 24 1,953 1,847 30 3,415 3,062 13 1,148 1,073 Home equity 11 351 349 14 395 366 5 95 192 Installment 2 35 22 2 41 39 0 0 0 Total 45 $ 17,323 $ 17,202 63 $ 31,884 $ 31,470 43 $ 28,571 $ 28,305 The following table provides information on how TDRs were modified during the years ended December 31, 2020, 2019 and 2018: Years Ended December 31, (Dollars in thousands) 2020 2019 2018 Extended maturities $ 0 $ 2,877 $ 4,093 Adjusted interest rates 0 5,284 52 Combination of rate and maturity changes 0 516 0 Forbearance 4,759 20,320 23,175 Other (1) 12,443 2,473 985 Total $ 17,202 $ 31,470 $ 28,305 (1) Other includes covenant modifications and other concessions or combination of concessions that do not consist of interest rate adjustments, forbearance and maturity extensions. First Financial considers repayment performance as an indication of the effectiveness of the Company's loan modifications. Borrowers that are 90 days or more past due on any principal or interest payments, or who prematurely terminate a restructured loan agreement without paying off the contractual principal balance, are considered to be in payment default of the terms of the TDR agreement. For the twelve months ended December 31, 2020, there was one TDR with an insignificant balance for which there was a payment default during the period that occurred within twelve months of the loan modification. For the twelve months ended December 31, 2019, there were three TDRs with a balance of $7.0 million for which there was a payment default during the period that occurred within twelve months of the loan modification. For the twelve months ended December 31, 2018, there was one TDR with an insignificant balance for which there was a payment default during the period that occurred within twelve months of the loan modification. As stated in the CARES Act and subsequently modified by the Consolidated Appropriations Act, loan modifications in response to COVID-19 executed on loans that were not more than 30 days past due as of December 31, 2019 and executed between March 1, 2020, and the earlier of 60 days after the date of termination of the National Emergency or January 1, 2022 are not required to be reported as a TDR. As of December 31, 2020, the Company's loan portfolio included $320.2 million of active modifications of which $18.5 million were from the first round of deferrals, $54.9 million were from the second round and $246.8 million were deferred a third time. Active full principal and interest modifications were $28.7 million at December 31, 2020, while $291.5 million of active modifications were making interest only payments at year end. Active modifications consist primarily of hotel and franchise loans, which were $186.2 million and $44.3 million respectively as of December 31, 2020, or 58% and 14% of the total active modifications at December 31, 2020. As of December 31, 2020, the Company's loan portfolio included 90 commercial loans with balances of $312.5 million and 53 consumer loans with balances of $7.7 million that were modified in response to COVID-19 that are not considered TDRs. Nonperforming loans. Loans classified as nonaccrual and loans modified as TDRs are considered nonperforming for 2020 and impaired as of December 31, 2019. The following table provides information on nonperforming loans as of December 31: 2020 2019 2018 (Dollars in thousands) Nonaccrual loans with a related ACL Nonaccrual loans with no related ACL Total nonaccrual Total nonaccrual Total nonaccrual Nonaccrual loans (1) Commercial & industrial $ 18,711 $ 10,519 $ 29,230 $ 24,346 $ 30,925 Lease financing 0 0 0 223 22 Construction real estate 0 0 0 0 9 Commercial real estate 6,957 27,725 34,682 7,295 20,500 Residential real estate 251 11,350 11,601 10,892 13,495 Home equity 0 5,076 5,076 5,242 5,580 Installment 0 163 163 167 169 Total nonaccrual loans $ 25,919 $ 54,833 $ 80,752 $ 48,165 $ 70,700 Interest income effect Gross amount of interest that would have been recorded under original terms $ 5,892 $ 5,813 $ 4,656 Interest included in income Nonaccrual loans 1,636 1,042 715 Troubled debt restructurings 426 801 642 Total interest included in income 2,062 1,843 1,357 Net impact on interest income $ 3,830 $ 3,970 $ 3,299 Commitments outstanding to borrowers with nonaccrual loans $ 0 $ 3 $ 200 (1) Nonaccrual loans include nonaccrual TDRs of $14.7 million, $18.5 million and $22.4 million as of December 31, 2020, 2019 and 2018, respectively. First Financial individually reviews all nonperforming loan relationships greater than $250,000 to determine if an individually evaluated allowance is necessary based on the borrower’s overall financial condition, resources and payment record, support from guarantors and the realizable value of any collateral. Individually evaluated allowances are based on discounted cash flows using the loan's initial effective interest rate or the fair value of the collateral for certain collateral dependent loans. First Financial's investment in impaired loans was as follows: December 31, 2019 (Dollars in thousands) Current balance Contractual Related Loans with no related allowance recorded Commercial & industrial $ 16,726 $ 19,709 $ 0 Lease financing 223 223 0 Construction real estate 0 0 0 Commercial real estate 10,160 17,897 0 Residential real estate 14,868 17,368 0 Home equity 5,700 6,462 0 Installment 204 341 0 Total 47,881 62,000 0 Loans with an allowance recorded Commercial & industrial 10,754 21,513 2,044 Lease financing 0 0 0 Construction real estate 0 0 0 Commercial real estate 671 675 113 Residential real estate 294 294 18 Home equity 0 0 0 Installment 0 0 0 Total 11,719 22,482 2,175 Total Commercial & industrial 27,480 41,222 2,044 Lease financing 223 223 0 Construction real estate 0 0 0 Commercial real estate 10,831 18,572 113 Residential real estate 15,162 17,662 18 Home equity 5,700 6,462 0 Installment 204 341 0 Total $ 59,600 $ 84,482 $ 2,175 Years ended December 31, 2019 2018 (Dollars in thousands) Average Interest Average Interest Loans with no related allowance recorded Commercial & industrial $ 31,846 $ 926 $ 14,498 $ 360 Lease financing 168 0 21 0 Construction real estate 6 0 20 2 Commercial real estate 18,757 357 24,738 490 Residential real estate 15,915 307 11,359 301 Home equity 5,893 121 5,541 114 Installment 170 2 274 2 Total 72,755 1,713 56,451 1,269 Loans with an allowance recorded Commercial & industrial 4,721 87 900 44 Lease financing 57 0 0 0 Construction real estate 0 0 0 0 Commercial real estate 1,339 31 1,402 18 Residential real estate 446 12 895 23 Home equity 0 0 80 3 Installment 0 0 0 0 Total 6,563 130 3,277 88 Total Commercial & industrial 36,567 1,013 15,398 404 Lease financing 225 0 21 0 Construction real estate 6 0 20 2 Commercial real estate 20,096 388 26,140 508 Residential real estate 16,361 319 12,254 324 Home equity 5,893 121 5,621 117 Installment 170 2 274 2 Total $ 79,318 $ 1,843 $ 59,728 $ 1,357 A loan is considered to be collateral dependent when the borrower is experiencing financial difficulty and the repayment is expected to be provided substantially through the operation or sale of collateral. The following table presents the amortized cost basis of collateral dependent loans by class of loan. December 31, 2020 Type of Collateral (Dollar in thousands) Business assets Commercial real estate Equipment Land Residential real estate Other Total Class of loan Commercial & industrial $ 30,961 $ 6,130 $ 2,608 $ 865 $ 0 $ 4,892 $ 45,456 Commercial real estate-investor 0 20,212 661 5,537 872 0 27,282 Commercial real estate-owner 5,842 3,495 0 42 344 0 9,723 Residential real estate 0 0 0 0 11,601 0 11,601 Home equity 0 0 0 0 5,076 0 5,076 Installment 0 0 0 0 0 163 163 Total $ 36,803 $ 29,837 $ 3,269 $ 6,444 $ 17,893 $ 5,055 $ 99,301 Lease financing. The Company prospectively applied FASB ASC Topic 842 in the first quarter of 2019. First Financial originates both sales-type and direct financing leases, and the Company manages and reviews lease residuals in accordance with its credit policies. Sales-type lease contracts contain the ability to purchase the underlying equipment at lease maturity and profit or loss is recognized at lease commencement. Direct financing leases are generally three to five years in length and may be extended at maturity, however, early cancellation may result in a fee to the borrower. For direct financing leases, the net unearned income is deferred and amortized over the life of the lease. Income recognized in 2020 and 2019 related to the implementation of FASB ASC Topic 842 was insignificant. OREO. OREO is comprised of properties acquired by the Company primarily through the loan foreclosure or repossession process, that result in partial or total satisfaction of problem loans. Changes in OREO were as follows: Years ended December 31, (Dollars in thousands) 2020 2019 2018 Balance at beginning of year $ 2,033 $ 1,401 $ 2,781 Additions Commercial 510 415 1,269 Residential 507 2,033 1,913 Total additions 1,017 2,448 3,182 Disposals Commercial (217) (541) (2,967) Residential (1,859) (912) (830) Total disposals (2,076) (1,453) (3,797) Valuation adjustments Commercial 448 (112) (355) Residential (135) (251) (410) Total valuation adjustments 313 (363) (765) Balance at end of year $ 1,287 $ 2,033 $ 1,401

ALLOWANCE FOR CREDIT LOSSES

ALLOWANCE FOR CREDIT LOSSES	12 Months Ended
	Dec. 31, 2020
Receivables [Abstract]
ALLOWANCE FOR LOAN AND LEASE LOSSES	Allowance for Credit Losses Allowance for credit losses - loans and leases. The allowance for credit losses is a valuation account that is deducted from the loans’ amortized cost basis to present the net amount expected to be collected on the loans. The ACL is increased by provision expense and decreased by charge-offs, net of recoveries of amounts previously charged-off. First Financial's policy is to charge-off all or a portion of a loan when, in management's opinion, it is unlikely to collect the principal amount owed in full either through payments from the borrower or a guarantor or from the liquidation of collateral. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged-off. Accrued interest receivable on loans and leases, which totaled $37.7 million as of December 31, 2020 , is excluded from the estimate of credit losses. Management estimates the allowance balance using relevant available information from both internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience paired with economic forecasts provide the basis for the quantitatively modeled estimation of expected credit losses. First Financial adjusts its quantitative model, as necessary, to reflect conditions not already considered by the quantitative model. These adjustments are commonly known as the Qualitative Framework. The allowance for credit losses is measured on a collective (pool) basis when similar risk characteristics exist. The Company has identified the following portfolio segments and measures the ACL using the following methods: Commercial and industrial – C&I loans include revolving lines of credit and term loans to commercial customers for use in normal business operations to finance working capital needs, equipment purchases, leasehold improvements or other projects. C&I loans are generally underwritten individually and secured with the assets of the Company and/or the personal guarantee of the business owners. C&I loans also include ABL, equipment and leasehold improvement financing for franchisees in the quick service and casual dining restaurant sector and commission-based loans to insurance agents and brokers. ABL transactions typically involve larger commercial clients and are secured by specific assets, such as inventory, accounts receivable, machinery and equipment. In the franchise lending space, First Financial focuses on a limited number of restaurant concepts that have sound economics, low closure rates and strong brand awareness within specified local, regional or national markets. Within the insurance lending platform, First Financial serves insurance agents and brokers that are looking to maximize their book-of-business value and grow their agency business. Current period default rates are utilized in the modeling of the ACL for C&I loans, and are adjusted for forecasted changes in the treasury term spread and market volatility index. Changes in current period defaults or forecasted expectations for these economic variables could result in volatility in the Company's ACL in future periods. Lease financing – Lease financing consists of lease transactions for the acquisition of both new and used business equipment for commercial clients. Lease products may include tax leases, finance leases, lease lines of credit and interim funding. The credit underwriting for lease transactions includes detailed analysis of the lessee's industry and business model, nature of the equipment, equipment resale values, historical and projected cash flow analysis, secondary sources of repayment and guarantor in addition to other considerations. The ACL model for leases sources expected default rates from the C&I portfolio model. Therefore, changes in forecasted expectations for the treasury term spread and market volatility index could result in volatility in the Company's ACL in future periods. Construction real estate – Real estate construction loans are term loans to individuals, companies or developers used for the construction or development of a commercial or residential property for which repayment will be generated by the sale or permanent financing of the property. Generally, these loans are for construction projects that have been pre-sold, pre-leased or have secured permanent financing, as well as loans to real estate companies with significant equity invested in the project. An independent credit team underwrites construction real estate loans, which are managed by experienced lending officers and monitored through the construction phase by a centralized funding desk that manages loan disbursements. The ACL model for construction is adjusted for forecasted changes in rental vacancy rates in the Bank's geographic footprint and the housing price index. Changes in forecasted expectations for these economic variables could result in volatility in the Company's ACL in future periods. Commercial real estate - owner & investor – Commercial real estate loans consist of term loans secured by a mortgage lien on real estate properties such as apartment buildings, office and industrial buildings and retail shopping centers. Additionally, the Company's franchise lending activities discussed in the "Commercial and Industrial" section often include the financing of real estate in addition to equipment. The credit underwriting for both owner-occupied and investor income producing real estate loans includes detailed market analysis, historical and projected cash flow analysis, appropriate equity margins, assessment of lessees and lessors, environmental risks and the type, age, condition and location of real estate, among other factors. First Financial models owner-occupied and investor CRE separately when determining the ACL. For owner occupied CRE, current period default rates are utilized in the modeling, and are adjusted for forecasted changes in the BAA bond spread, national rental vacancy rates and the consumer confidence index. Current period default rates are also utilized in the modeling of investor CRE loans, and are adjusted for forecasted changes in the BAA bond spread, multifamily building permits within the Bank’s geographic footprint, and national rental vacancy rates. Changes in current period defaults and forecasted expectations for these economic variables could result in volatility in the Company's ACL in future periods. Residential real estate – Residential real estate loans represent loans to consumers for the financing of a residence. These loans generally have a 15 to 30 year term and a fixed interest rate, but may have a shorter term to maturity with an adjustable interest rate. In most cases, these loans are extended to borrowers to finance their primary residence. First Financial sells residential real estate loan originations into the secondary market on both servicing retained and servicing released bases. Residential real estate loans are generally underwritten to secondary market lending standards, utilizing underwriting processes that rely on empirical data to assess credit risk as well as analysis of the borrower's ability to repay their obligations, credit history, the amount of any down payment and the market value or other characteristics of the property. First Financial also offers a residential mortgage product that features similar borrower credit characteristics but a more streamlined underwriting process than typically required to sell to government-sponsored enterprises and thus is retained on the Consolidated Balance Sheets. The retail real estate ACL model is adjusted for forecasted changes in the housing price index, housing starts within the Bank’s geographic footprint and national single-family existing home sa l es. Changes in forecasted expectations for these economic variables could result in volatility in the Company's ACL in future periods. Home equity – Home equity lending includes both home equity loans and revolving lines of credit secured by a first or second lien on the borrower’s residence. Home equity lending underwriting considerations include the borrower's credit history as well as to debt-to-income and loan-to-value policy limits. The home equity ACL model is adjusted for forecasted changes in the consumer credit growth rate within the Bank’s geographic footprint and the working-age labor participation rate. Changes in forecasted expectations for these economic variables could result in volatility in the Company's ACL in future periods. Installment – Installment lending consists of consumer loans not secured by real estate, including loans secured by automobiles and unsecured personal loans. The ACL model for installment loans sources expected default rates from the residential real estate and home equity portfolio models and is paired with installment specific LGD rates. Changes in forecasted expectations for the consumer credit growth rate within the Bank’s geographic footprint, the working-age labor participation rate, the housing price index, housing starts within the Bank’s geographic footprint and national existing single-family existing home sa l es could result in volatility in the Company's ACL in future periods. Credit card – Credit card lending consists of secured and unsecured revolving lines of credit to consumer and business customers. Credit card lines are generally available for an indefinite period of time as long as the borrower's credit characteristics do not materially or adversely change, but lines are unconditionally cancellable by the Company at any time. The ACL model for credit card loans sources expected default rates from the residential real estate and home equity portfolio models and is paired with credit card specific LGD rates. Changes in forecasted expectations for the consumer credit growth rate within the Bank’s geographic footprint, the working-age labor participation rate, the housing price index, housing starts within the Bank’s geographic footprint and national existing single-family existing home sa l es could result in volatility in the Company's ACL in future periods. The Company utilized the Moody's December baseline forecast as its R&S forecast in the quantitative model, which included consideration of the impact from both the COVID-19 pandemic and the related government stimulus response at the time. For reasonableness, the Company also considered the impact to the model from alternative, more adverse economic forecasts, slower prepayment speeds and increased default rates. These alternative analyses were utilized to inform the Company's qualitative adjustments. Additionally, First Financial considered its credit exposure to certain industries believed to be at risk for future credit stress related to the COVID-19 pandemic, such as franchise, hotel and investor commercial real estate lending when making qualitative adjustments to the ACL model. First Financial's ACL is influenced by loan volumes, risk rating migration or delinquency status, and other conditions influencing loss expectations, such as reasonable and supportable forecasts of economic conditions. For the twelve months ended December 31, 2020 the ACL increased due to First Financial's adoption of ASC 326 and management's expectation of higher credit losses resulting from the COVID-19 pandemic. Changes in the allowance by loan category as of December 31 were as follows: 2020 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Allowance for credit losses Beginning balance, prior to adoption of ASC 326 $ 18,584 $ 971 $ 2,381 $ 23,579 $ 5,299 $ 4,787 $ 392 $ 1,657 $ 57,650 Impact of adopting ASC 326 9,901 118 11,579 24,118 5,490 8,430 801 1,068 61,505 Provision for credit losses 25,407 758 7,759 38,936 (2,122) (939) 12 985 70,796 Gross charge-offs (5,345) (852) 0 (12,100) (488) (1,541) (148) (885) (21,359) Recoveries 2,907 0 17 2,262 381 1,132 158 230 7,087 Total net charge-offs (2,438) (852) 17 (9,838) (107) (409) 10 (655) (14,272) Ending allowance for credit losses $ 51,454 $ 995 $ 21,736 $ 76,795 $ 8,560 $ 11,869 $ 1,215 $ 3,055 $ 175,679 2019 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Allowance for credit losses Balance at beginning of year $ 18,746 $ 1,130 $ 3,413 $ 21,048 $ 4,964 $ 5,348 $ 362 $ 1,531 $ 56,542 Provision for credit losses 23,631 3 (1,100) 5,107 739 695 2 1,521 30,598 Gross charge-offs (26,676) (162) 0 (3,689) (677) (2,591) (223) (1,547) (35,565) Recoveries 2,883 0 68 1,113 273 1,335 251 152 6,075 Total net charge-offs (23,793) (162) 68 (2,576) (404) (1,256) 28 (1,395) (29,490) Ending allowance for credit losses $ 18,584 $ 971 $ 2,381 $ 23,579 $ 5,299 $ 4,787 $ 392 $ 1,657 $ 57,650 2018 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Allowance for credit losses Balance at beginning of year $ 17,598 $ 675 $ 3,577 $ 20,930 $ 4,683 $ 4,935 $ 307 $ 1,316 $ 54,021 Provision for credit losses 10,615 454 (310) 847 492 829 (85) 1,744 14,586 Gross charge-offs (11,533) 0 0 (4,835) (422) (1,725) (435) (1,720) (20,670) Recoveries 2,066 1 146 4,106 211 1,309 575 191 8,605 Total net charge-offs (9,467) 1 146 (729) (211) (416) 140 (1,529) (12,065) Ending allowance for credit losses $ 18,746 $ 1,130 $ 3,413 $ 21,048 $ 4,964 $ 5,348 $ 362 $ 1,531 $ 56,542 As of December 31, 2019 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Ending allowance balance attributable to loans Individually evaluated for impairment $ 2,044 $ 0 $ 0 $ 113 $ 18 $ 0 $ 0 $ 0 $ 2,175 Collectively evaluated for impairment 16,540 971 2,381 23,466 5,281 4,787 392 1,657 55,475 Ending allowance for credit losses $ 18,584 $ 971 $ 2,381 $ 23,579 $ 5,299 $ 4,787 $ 392 $ 1,657 $ 57,650 Loans Individually evaluated for impairment $ 27,480 $ 223 $ 0 $ 10,831 $ 15,162 $ 5,700 $ 204 $ 0 $ 59,600 Collectively evaluated for impairment 2,438,397 88,141 493,182 4,183,820 1,040,787 766,169 82,385 49,184 9,142,065 Total loans $ 2,465,877 $ 88,364 $ 493,182 $ 4,194,651 $ 1,055,949 $ 771,869 $ 82,589 $ 49,184 $ 9,201,665 Allowance for credit losses - unfunded commitments. First Financial estimates expected credit losses over the contractual period in which the Company is exposed to credit risk via a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by the Company. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on commitments expected to be funded over its estimated life consistent with the Company's ACL methodology for loans and leases. Prior to the adoption of ASC 326, First Financial maintained its reserve to absorb probable losses incurred in standby letters of credit and outstanding loan commitments. First Financial determined the adequacy of this reserve based upon an evaluation of the unfunded credit facilities, which included consideration of historical commitment utilization experience, credit risk ratings and historical loss rates, consistent with the Company's ALLL methodology at the time. The ACL on unfunded commitments was $12.5 million as of December 31, 2020 and $0.6 million as of December 31, 2019. Due to the adoption of ASC 326, First Financial recorded $12.2 million in the ACL on unfunded commitments. Additionally, First Financial recorded $0.2 million of provision recapture related to the ACL on unfunded commitments for the twelve months ended December 31, 2020 and December 31, 2019.

PREMISES AND EQUIPMENT

PREMISES AND EQUIPMENT	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
PREMISES AND EQUIPMENT	Premises and Equipment Premises and equipment at December 31 were as follows: (Dollars in thousands) 2020 2019 Land and land improvements $ 52,373 $ 54,958 Buildings 161,371 163,277 Furniture and fixtures 70,177 74,881 Leasehold improvements 29,525 31,728 Construction in progress 8,434 4,096 321,880 328,940 Less: Accumulated depreciation and amortization 114,669 114,434 Total $ 207,211 $ 214,506 Rental expense recorded under operating leases in 2020, 2019 and 2018 was $9.1 million, $11.2 million and $9.1 million, respectively.

LEASES

LEASES	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	Leases A lease is defined as a contract, or part of a contract, that conveys the right to control the use of identified property, plant or equipment for a period of time in exchange for consideration. First Financial is primarily the lessee in its leasing agreements, and substantially all of those agreements are for real estate property for branches, ATM locations and office space. On January 1, 2019, the Company adopted Topic 842 and all subsequent modifications. For First Financial, this adoption primarily affected the accounting treatment for operating lease agreements in which the Company is the lessee. Substantially all of the Company's leases are classified as operating leases, and therefore, were previously not recognized on the Company’s Consolidated Balance Sheets. With the adoption of Topic 842, operating lease agreements were required to be recognized on the Consolidated Balance Sheets as an ROU asset and a corresponding lease liability. The Company's right to use an asset over the life of a lease is recorded as a "right of use" asset in Accrued interest and other assets on the Consolidated Balance Sheet and was $63.9 million and $58.6 million at December 31, 2020 and 2019, respectively. Certain adjustments to the ROU asset may be required for items such as initial direct costs paid or incentives received. First Financial recorded a $ 71.7 million 64.3 million The calculated amount of the ROU assets and lease liabilities are impacted by the length of the lease term and the discount rate used to calculate the present value of minimum lease payments. Regarding the discount rate, Topic 842 requires the use of the rate implicit in the lease whenever this rate is readily determinable. As this rate is rarely determinable, the Company utilizes its incremental borrowing rate at lease inception, on a collateralized basis, over a similar term. For operating leases existing prior to January 1, 2019, the rate was based upon the remaining lease term as of that date. Leases with an initial term of 12 months or less are not recorded on the balance sheet and First Financial recognizes lease expense for these leases on a straight-line basis over the term of the lease. Most leases include one or more options to renew, with renewal terms that can extend the lease term from one to 20 years or more. The exercise of renewal options on operating leases is at the Company's sole discretion, and certain leases may include options to purchase the leased property. If at lease inception, the Company considers the exercising of a renewal option to be reasonably certain, the Company will include the extended term in the calculation of the ROU asset and lease liability. First Financial does not enter into lease agreements which contain material residual value guarantees or material restrictive covenants. Certain leases provide for increases in future minimum annual rental payments as defined in the lease agreements and leases generally also include real estate taxes and common area maintenance charges in the annual rental payments. The components of lease expense for the years ended December 31, 2020 and 2019 were as follows: (dollars in thousands) December 31, 2020 December 31, 2019 Operating lease cost $ 7,897 $ 7,324 Short-term lease cost 142 55 Variable lease cost 2,532 2,553 Total operating lease cost $ 10,571 $ 9,932 Future minimum commitments due under these lease agreements as of December 31, 2020 are as follows: (dollars in thousands) Operating leases 2021 $ 6,864 2022 7,074 2023 7,143 2024 6,858 2025 6,217 Thereafter 56,951 Total lease payments 91,107 Less imputed interest 19,395 Total $ 71,712 The weighted average lease term and discount rate for the Company's operating leases were as follows: December 31, 2020 December 31, 2019 Operating leases Weighted-average remaining lease term 15.1 years 15.6 years Weighted-average discount rate 3.07 % 3.43 % Supplemental cash information at year end related to leases was as follows: (dollars in thousands) December 31, 2020 December 31, 2019 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from operating leases $ 8,196 $ 7,335 ROU assets obtained in exchange for lease obligations Operating leases 9,725 64,902

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	Goodwill and Other Intangible Assets Goodwill. Assets and liabilities acquired in a business combination are recorded at their estimated fair values as of the acquisition date. The excess of the purchase price of the acquisition over the fair value of net assets acquired is recorded as goodwill. Changes in the carrying amount of goodwill for the years ended December 31, 2020, 2019 and 2018 are shown below. (Dollars in thousands) 2020 2019 2018 Balance at beginning of year $ 937,771 $ 880,251 $ 204,084 Goodwill resulting from business combinations 0 57,520 676,167 Balance at end of year $ 937,771 $ 937,771 $ 880,251 During 2019, First Financial recorded $58.0 million of additions to goodwill resulting from the Bannockburn acquisition. During 2018, First Financial recorded additions to goodwill of $676.2 million resulting from the merger with MSFG, and First Financial recorded its final adjustments to goodwill related to the MSFG merger in the first quarter of 2019. For further detail on the merger with MSFG or the acquisition of Bannockburn, see Note 23 - Business Combinations. Goodwill is evaluated for impairment on an annual basis as of October 1 of each year, or whenever events or changes in circumstances indicate that the fair value of a reporting unit may be below its carrying value. First Financial engaged a third party to perform a quantitative analysis of its goodwill to determine whether any impairment existed as of October 1, 2020 for its annual impairment test. This quantitative analysis was performed due to the on-going economic market disruption, the movement of the Company’s stock price in relation to other bank indexes and the length of time that the market value of the reporting unit had been below its book value. This analysis indicated that no impairment existed as of the issue date. Our quantitative impairment analysis utilized the discounted cash flow model for the income approach and the market multiple methodology and comparable transaction methodology as the market approach. These valuation methodologies utilize key assumptions that include forecasts of revenues and expenses derived from internal management projections for a period of five years, changes in working capital estimates, company specific discount rate derived from a rate build up approach, externally sourced bank peer group market multiples and externally sourced bank peer group change in control premium, all of which are highly subjective and require significant management judgment. Changes in these key assumptions could materially affect our estimate of the reporting unit fair value and could affect our conclusion regarding the existence of potential impairment. Additionally, in response to the COVID-19 pandemic and the related deterioration in general economic conditions, First Financial performed an interim qualitative impairment test as of the end of each quarter in 2020, including the quarter ended December 31, 2020. Likewise, the results of this interim qualitative tests performed did not indicate that the Company's goodwill was impaired. First Financial will continue to monitor the status of its goodwill and intangible assets for signs of further deterioration and potential impairment. Other intangible assets. Other intangible assets consist primarily of core deposit, customer list and other miscellaneous intangibles. Core deposit intangibles represent the estimated fair value of acquired customer deposit relationships on the date of acquisition and are amortized on an accelerated basis over their estimated useful lives. First Financial's core deposit intangibles have an estimated weighted average remaining life of 7.1 years. First Financial recorded a $39.4 million customer list intangible asset in conjunction with the Bannockburn merger to account for the obligation or advantage on the part of either the Company or the customer to continue the pre-existing relationship subsequent to the merger. The customer list intangible asset is being amortized on a straight-line basis over its estimated useful life of 11 years. Other miscellaneous intangibles include purchase commissions, non-compete agreements and trade name intangibles. Other intangible assets are included in Other intangibles in the Consolidated Balance Sheets. The gross carrying amount and accumulated amortization of other intangible assets at December 31, 2020 and December 31, 2019 were as follows: (Dollars in thousands) December 31, 2020 December 31, 2019 Amortized intangible assets Core deposit intangibles $ 51,031 $ (27,524) $ 51,031 $ (21,149) Customer list 39,420 (4,778) 39,420 (1,195) Other 10,113 (3,710) 10,093 (1,999) Total $ 100,564 $ (36,012) $ 100,544 $ (24,343) Amortization expense recognized on intangible assets for 2020, 2019 and 2018 was $11.1 million, $9.7 million and $7.4 million, respectively. The estimated amortization expense of intangible assets for the next five years is as follows: (Dollars in thousands) Intangible amortization 2021 $ 10,249 2022 7,708 2023 6,729 2024 6,660 2025 6,611

BORROWINGS

BORROWINGS	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
BORROWINGS	BorrowingsShort-term borrowings on the Consolidated Balance Sheets include repurchase agreements utilized for corporate sweep accounts with cash management account agreements in place, federal funds purchased and overnight advances from the FHLB. All repurchase agreements are subject to terms and conditions agreed to by the Bank and the client. To secure its liability to the client, the Bank is authorized to sell or repurchase U.S. Treasury, government agency and mortgage-backed securities. The following shows the remaining contractual maturity of repurchase agreements by collateral pledged: (Dollars in thousands) Overnight and Continuous Repurchase agreements Mortgage-backed securities $ 79,235 Collateralized mortgage obligations 47,359 Total $ 126,594 Securities sold under agreements to repurchase are secured by securities with a carrying amount of $126.7 million and $90.2 million, as of December 31, 2020 and 2019, respectively. The following is a summary of short-term borrowings for the last three years: 2020 2019 2018 (Dollars in thousands) Amount Rate Amount Rate Amount Rate At December 31, Federal funds purchased and securities sold under agreements to repurchase $ 166,594 0.05 % $ 165,181 0.85 % $ 183,591 1.65 % FHLB borrowings 0 0.00 % 1,151,000 1.73 % 857,100 2.48 % Total $ 166,594 0.05 % $ 1,316,181 1.62 % $ 1,040,691 2.33 % Average for the year Federal funds purchased and securities sold under agreements to repurchase $ 149,036 0.26 % $ 155,859 1.15 % $ 87,221 0.58 % FHLB borrowings 441,867 1.37 % 990,860 2.37 % 857,028 2.03 % Other short-term borrowings 0 0.00 % 0 0.00 % 3,178 4.36 % Total $ 590,903 1.09 % $ 1,146,719 1.90 % $ 947,427 1.90 % Maximum month-end balances Federal funds purchased and securities sold under agreements to repurchase $ 260,621 $ 260,621 $ 183,591 FHLB borrowings 1,171,400 1,171,400 1,170,800 Other short-term borrowings 0 0 10,000 During 2020 First Financial participated in the PPPLF, which is a program created by the FRB to extend credit to eligible financial institutions that originate PPP loans. The bank had outstanding PPPLF advances of $435.0 million as of December 31, 2020, with an average interest rate of 35 basis points. These borrowings are secured by pledged PPP loans and prepay in conjunction with reductions in the principal balances of those loans. In April 2020, First Financial issued $150.0 million of fixed to floating rate subordinated notes. The subordinated notes have an initial fixed interest rate of 5.25% to, but excluding, May 15, 2025, payable semi-annually in arrears. From, and including, May 15, 2025, the interest rate on the subordinated notes will reset quarterly to a floating rate per annum equal to a benchmark rate, which is expected to be the then-current three-month term SOFR, plus 509 basis points, payable quarterly in arrears. The subordinated notes mature on May 15, 2030. These notes are redeemable by the Company in whole or in part beginning with the interest payment date of May 15, 2025. In 2015, First Financial issued $120.0 million of subordinated notes, which have a fixed interest rate of 5.13% payable semiannually and mature in August 2025. These notes are not redeemable by the Company or callable by the holders of the notes prior to maturity. In addition, First Financial acquired $49.5 million of variable rate subordinated notes in the MSFG merger that were issued to previously formed trusts in exchange for the trust proceeds. Interest on the acquired subordinated notes is payable quarterly, in arrears, and the Company has the option to defer interest payments for a period not to exceed 20 consecutive quarters. The acquired subordinated notes mature 30 years after the date of original issuance and may be called at par following the 5 year anniversary of issuance. First Financial also acquired $8.4 million of 6.00% fixed rate private placement subordinated debt in conjunction with the MSFG merger that was issued in 2015 and matures in 2025. These notes are redeemable by the Company at par following the 5 year anniversary of issuance. The subordinated notes are treated as Tier 2 capital for regulatory capital purposes and are included in Long-term debt on the Consolidated Balance Sheets. In addition to subordinated notes, long-term debt included $20.0 million and $242.4 million of fixed rate FHLB long-term advances as of December 31, 2020 and December 31, 2019, respectively. As of December 31, 2020 and December 31, 2019, long-term FHLB advances had a weighted average interest rate of 1.43% and 1.94%, respectively. In the fourth quarter of 2020, First Financial redeemed $120.0 million of FHLB long-term advances with maturities of two to seven years. These instruments are primarily utilized to reduce overnight liquidity risk and to mitigate interest rate sensitivity on the Consolidated Balance Sheets. FHLB advances, both short-term and long-term, must be collateralized with qualifying assets, typically certain commercial and residential real estate loans, as well as certain government and agency securities. For ease of borrowing execution, First Financial utilizes a blanket collateral agreement with the FHLB, and at December 31, 2020, had collateral pledged with a book value of $6.3 billion. The following is a summary of First Financial's long-term debt: 2020 2019 (Dollars in thousands) Amount Average Rate Amount Average Rate FRB borrowings $ 434,982 0.35 % $ 0 n/a FHLB borrowings 19,971 1.43 % 242,428 1.94 % Subordinated debt 321,384 4.86 % 170,967 4.97 % Unamortized debt issuance costs (2,770) n/a (1,007) n/a Capital lease liability 1,860 3.81 % 1,213 4.48 % Capital loan with municipality 775 0.00 % 775 0.00 % Total long-term debt $ 776,202 2.25 % $ 414,376 3.20 % As of December 31, 2020, First Financial's long-term debt matures as follows: (Dollars in thousands) Long-term debt 2021 $ 20,050 2022 435,065 2023 87 2024 91 2025 96 Thereafter 320,813 Total $ 776,202

DERIVATIVES

DERIVATIVES	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVES	Derivatives First Financial uses certain derivative instruments, including rate caps, floors, swaps and foreign exchange contracts, to meet the operating needs of its clients while managing the interest and currency rate risk associated with certain transactions. First Financial may also utilize interest rate swaps to manage the interest rate risk profile of the Company. Interest rate payments are exchanged with counterparties, based on the notional amount as established in the interest rate agreement. As only interest rate payments are exchanged, the cash requirements and credit risk associated with interest rate swaps are significantly less than the notional amount and the Company’s credit risk exposure is limited to the market value of the instruments. First Financial does not use derivatives for speculative purposes. First Financial manages this market value credit risk through counterparty credit policies including a review of total derivative notional position to total assets, total credit exposure to total capital and counterparty credit exposure risk. For discussion of First Financial's accounting for derivative instruments, see Note 1 – Summary of Significant Accounting Policies. Client derivatives. First Financial utilizes interest rate swaps as a means to offer commercial borrowers fixed rate funding while providing the Company with floating rate assets. At December 31, 2020, for interest rate derivatives, the Company had a total counterparty notional amount outstanding of $2.3 billion, spread among twenty counterparties, with an outstanding liability from these contracts of $182.3 million. At December 31, 2019, the Company had interest rate derivatives with a total counterparty notional amount outstanding of $1.9 billion, spread among eighteen counterparties, with an outstanding liability from these contracts of $67.5 million. First Financial monitors its derivative credit exposure to borrowers by monitoring the creditworthiness of the related loan customers through the Company's normal credit review processes. Additionally, the Company's ACL Committee monitors derivative credit risk exposure associated with problem loans through the Company's ACL committee. First Financial considers the market value of a derivative instrument to be part of the carrying value of the related loan for these purposes as the borrower is contractually obligated to pay First Financial this amount in the event the derivative contract is terminated. In connection with its use of derivative instruments, First Financial and its counterparties may be required to post cash collateral to offset the market position of the derivative instruments. First Financial maintains the right to offset these derivative positions with the collateral posted against them by or with the relevant counterparties. Foreign Exchange Contracts. First Financial may enter into foreign exchange derivative contracts for the benefit of commercial customers to hedge their exposure to foreign currency fluctuations. Similar to the hedging of interest rate risk from interest rate derivative contracts, First Financial also enters into foreign exchange contracts with major financial institutions to economically hedge a substantial portion of the exposure from client driven foreign exchange activity. These derivatives are classified as free-standing instruments with the revaluation gain or loss recorded in Foreign exchange income in the Consolidated Statements of Income. The Company has risk limits and internal controls in place to help ensure excessive risk is not being taken in providing this service to customers. These controls include an independent determination of currency volatility and credit equivalent exposure on these contracts, counterparty credit approvals and country limits performed by independent risk management. At December 31, 2020, the Company had total counterparty notional amount outstanding of $3.6 billion spread among six counterparties, with an estimated fair value of $33.1 million at December 31, 2020 related to foreign exchange contracts, which is included in Accrued interest and other liabilities in the Consolidated Balance Sheets. At December 31, 2019, the Company had total counterparty notional amounts outstanding of $1.9 billion spread among six counterparties, with an estimated fair value of $18.3 million. In connection with its use of foreign exchange contracts, First Financial and its counterparties may be required to post cash collateral to offset the market position of the derivative instruments. First Financial maintains the right to offset these derivative positions with the collateral posted against them by or with the relevant counterparties. The following table details the location and amounts of client derivatives and foreign exchange contracts recognized in the Consolidated Balance Sheets: December 31, 2020 December 31, 2019 Estimated fair value Estimated fair value (Dollars in thousands) Balance Notional Gain Loss Notional Gain Loss Client derivatives-instruments associated with loans Matched interest rate swaps with borrower Accrued interest and other assets and other liabilities $ 2,300,336 $ 184,777 $ (107) $ 1,923,375 $ 70,799 $ (2,636) Matched interest rate swaps with counterparty Accrued interest and other liabilities 2,300,336 107 (184,884) 1,923,375 2,636 (70,808) Foreign exchange contracts Matched foreign exchange contracts with customers Accrued interest and other assets 3,637,509 60,366 (27,249) 1,869,934 28,739 (10,433) Match foreign exchange contracts with counterparty Accrued interest and other liabilities 3,637,509 27,249 (60,366) 1,869,934 10,433 (28,739) Total $ 11,875,690 $ 272,499 $ (272,606) $ 7,586,618 $ 112,607 $ (112,616) The following table discloses the gross and net amounts of client derivatives and foreign exchange contracts recognized in the Consolidated Balance Sheets: December 31, 2020 December 31, 2019 (Dollars in thousands) Gross amounts of recognized liabilities Gross amounts offset in the Consolidated Balance Sheets Net amounts of (assets)/liabilities presented in the Consolidated Balance Sheets Gross amounts of recognized liabilities Gross amounts offset in the Consolidated Balance Sheets Net amounts of (assets)/liabilities presented in the Consolidated Balance Sheets Client derivatives Matched interest rate swaps $ 184,991 $ (385,088) $ (200,097) $ 73,444 $ (147,193) $ (73,749) Foreign exchange contracts with counterparty 87,615 (17,392) 70,223 39,172 (41,202) (2,030) Total $ 272,606 $ (402,480) $ (129,874) $ 112,616 $ (188,395) $ (75,779) The following table details the derivative financial instruments, the average remaining maturities and the weighted-average interest rates being paid and received by First Financial at December 31, 2020: (Dollars in thousands) Notional Average Fair Client derivatives-interest rate contracts Receive fixed, matched interest rate swaps with borrower $ 2,300,336 4.9 $ 184,670 Pay fixed, matched interest rate swaps with counterparty 2,300,336 4.9 (184,777) Client derivatives-foreign exchange contracts Foreign exchange contracts - pay USD 3,637,509 0.6 33,117 Foreign exchange contracts - receive USD 3,637,509 0.6 (33,117) Total client derivatives $ 11,875,690 2.3 $ (107) Credit derivatives. In conjunction with participating interests in commercial loans, First Financial periodically enters into risk participation agreements with counterparties whereby First Financial assumes a portion of the credit exposure associated with an interest rate swap on the participated loan in exchange for a fee. Under these agreements, First Financial will make payments to the counterparty if the loan customer defaults on its obligation to perform under the interest rate swap contract with the counterparty. The total notional value of these agreements totaled $242.4 million as of December 31, 2020 and $216.2 million as of December 31, 2019. The fair value of these agreements were recorded in Accrued interest and other liabilities on the Consolidated Balance Sheets was $0.3 million at December 31, 2020 and $0.2 million at December 31, 2019. Mortgage Derivatives. First Financial enters into IRLCs and forward commitments for the future delivery of mortgage loans to third party investors, which are considered derivatives. When borrowers secure an IRLC with First Financial and the loans are intended to be sold, First Financial will enter into forward commitments for the future delivery of the loans to third party investors in order to hedge against the effect of changes in interest rates impacting IRLCs and and loans held for sale. At December 31, 2020, the notional amount of the IRLCs was $114.2 million and the notional amount of forward commitments was $112.6 million. As of December 31, 2019, the notional amount of IRLCs was $33.4 million and the notional amount of forward commitments was $37.8 million. The fair value of these agreements was $2.7 million at December 31, 2020 and was $0.9 million at December 31, 2019 and was recorded in Accrued interest and other assets on the Consolidated Balance Sheets.

RELATED PARTIES TRANSACTIONS

RELATED PARTIES TRANSACTIONS	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Loans to Related Parties	Related Party Transactions Outstanding balance of loans to directors, executive officers, principal holders of First Financial’s common stock and certain related persons were as follows: (Dollars in thousands) 2020 Beginning balance $ 5,289 Additions 1,811 Deductions (2,003) Ending balance $ 5,097 Loans 90 days or more past due $ 0

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	Commitments and Contingencies First Financial offers a variety of financial instruments including letters of credit and outstanding commitments to extend credit to assist clients in meeting their requirement for liquidity and credit enhancement. GAAP does not require these financial instruments to be recorded in the Consolidated Financial Statements. First Financial utilizes the same credit policies in issuing commitments and conditional obligations as it does for credit instruments recorded on the Consolidated Balance Sheets. First Financial’s exposure to credit loss in the event of nonperformance by the counterparty was represented by the contractual amounts of those instruments. Effective January 1, 2020, First Financial adopted ASC 326, at which time First Financial estimated credit losses over the contractual period in which the Company is exposed to credit risk via a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by the Company. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on commitments expected to be funded over its estimated useful life consistent with the Company's ACL methodology for loans and leases. Adjustments to the reserve for unfunded commitments are recorded in Provision for credit losses - unfunded commitments in the Consolidated Statements of Income. First Financial had $12.5 million of ACL for unfunded commitments recorded in Accrued interest and other liabilities on the Consolidated Balance Sheets as of December 31, 2020. Prior to the adoption of ASC 326, First Financial maintained its reserve to absorb probable losses incurred in standby letters of credit and outstanding loan commitments. First Financial determined the adequacy of this reserve based upon an evaluation of the unfunded credit facilities, which included consideration of historical commitment utilization experience, credit risk ratings and historical loss rates, consistent with the Company's ALLL methodology at the time. First Financial had $0.6 million of reserves for unfunded commitments recorded in Accrued interest and other liabilities on the Consolidated Balance Sheets as of December 31, 2019. Loan commitments. Loan commitments are agreements to extend credit to a client absent any violation of any condition established in the commitment agreement. 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 cash requirements. The amount of collateral obtained, if deemed necessary by First Financial upon extension of credit, is based on management’s credit evaluation of the client. The collateral held varies, but may include securities, real estate, inventory, plant or equipment. First Financial had commitments outstanding to extend credit, totaling $3.4 billion and $3.3 billion at December 31, 2020 and 2019, respectively. As of December 31, 2020, loan commitments with a fixed interest rate totaled $123.6 million while commitments with variable interest rates totaled $3.3 billion. At December 31, 2019, loan commitments with a fixed interest rate totaled $123.7 million while commitments with variable interest rates totaled $3.2 billion. The fixed rate loan commitments have interest rates ranging from 0.00% to 21.00% for both December 31, 2020 and 2019 and have maturities ranging from less than 1 year to 30.8 years for December 31, 2020 and less than 1 year to 31.6 years for December 31, 2019. The following table presents First Financial's loan balances and contractual obligations to extend credit as of December 31, 2020. (dollars in thousands) Unfunded commitment Loan balance Commercial & industrial $ 1,270,765 $ 3,007,509 Lease financing 0 72,987 Construction real estate 374,008 636,096 Commercial real estate-investor 139,754 3,244,540 Commercial real estate-owner 51,637 1,063,318 Residential real estate 28,895 1,003,086 Home equity 762,406 743,099 Installment 18,229 81,850 Credit card 207,365 48,485 Total $ 2,853,059 $ 9,900,970 Letters of credit. Letters of credit are conditional commitments issued by First Financial to guarantee the performance of a client to a third party. First Financial’s portfolio of letters of credit consists primarily of performance assurances made on behalf of clients who have a contractual commitment to produce or deliver goods or services. The risk to First Financial arises from its obligation to make payment in the event of the client's contractual default to produce the contracted good or service to a third party. First Financial has issued letters of credit aggregating $36.1 million and $33.4 million at December 31, 2020, and 2019, respectively. Management conducts regular reviews of these instruments on an individual client basis. Investments in affordable housing projects. First Financial has made investments in certain qualified affordable housing tax credits that are accounted for under ASU 2014-01, Accounting for Investments in Affordable Housing Projects. These credits are an indirect federal subsidy that provide tax incentives to encourage investment in the development, acquisition and rehabilitation of affordable rental housing, and allow investors to claim tax credits and other tax benefits (such as deductions from taxable income for operating losses) on their federal income tax returns. The principal risk associated with qualified affordable housing investments is the potential for noncompliance with the tax code requirements, such as failure to rent property to qualified tenants, resulting in the unavailability or recapture of the tax credits and other tax benefits. Investments in affordable housing projects are accounted for under the proportional amortization method and are included in Accrued interest and other assets in the Consolidated Balance Sheets. First Financial's affordable housing commitments totaled $47.5 million and $38.5 million as of December 31, 2020 and 2019, respectively. The Company recognized tax credits of $7.6 million, $6.2 million and $4.9 million related to its investments in affordable housing projects for the years ended December 31, 2020, 2019 and 2018, respectively. The Company recognized amortization expense which was included in income tax expense of $8.1 million, $6.9 million and $5.7 million for the years ended December 31, 2020, 2019 and 2018, respectively. First Financial had no affordable housing contingent commitments as of December 31, 2020 or December 31, 2019. Investments in historic tax credits. First Financial has noncontrolling financial investments in private investment funds and partnerships which are not consolidated. These investments may generate a return through the realization of federal and state income tax credits, as well as other tax benefits, such as tax deductions from net operating losses of the investments over a period of time. Investments in historic tax credits are accounted for under the equity method of accounting and are included in Accrued interest and other assets on the Consolidated Balance Sheets. The Company’s recorded investment in these entities was approximately $3.6 million at December 31, 2020, and $3.1 million at December 31, 2019. The maximum exposure to loss related to these investments was $4.0 million at December 31, 2020 and $5.1 million at December 31, 2019, representing the Company’s investment balance and its unfunded commitments to invest additional amounts. Investments in historic tax credits resulted in $0.6 million, $3.5 million and $0.5 million of tax credits for the years ended December 31, 2020, 2019 and 2018, respectively. Investments in renewable energy tax credits. During 2020, First Financial invested in a renewable energy project where it has noncontrolling interest which is not consolidated. This investment may generate a return through the realization of federal and state income tax credits, as well as other tax benefits, such as tax deductions from net operating losses of the investments over a period of time. Investments in renewable energy tax credits are accounted for under the equity method of accounting and are included in Accrued interest and other assets on the Consolidated Balance Sheets. The Company’s recorded investment in this project was approximately $5.2 million at December 31, 2020. The maximum exposure to loss related to this investment was $7.7 million, representing the Company’s investment balance and its unfunded commitments to invest additional amounts. The investment in renewable energy tax credits resulted in $4.8 million of tax credits for the year ended December 31, 2020. Contingencies/Litigation. First Financial and its subsidiaries are engaged in various matters of litigation from time to time, and have a number of unresolved claims pending. Additionally, as part of the ordinary course of business, First Financial and its subsidiaries are parties to litigation involving claims to the ownership of funds in particular accounts, the collection of delinquent accounts, challenges to security interests in collateral and foreclosure interests, that is incidental to our regular business activities. While the ultimate liability with respect to these litigation matters and claims cannot be determined at this time, First Financial believes that damages, if any, and other amounts relating to pending matters are not probable or cannot be reasonably estimated as of December 31, 2020. Reserves are established for these various matters of litigation, when appropriate, under FASB ASC Topic 450, Contingencies, based in part upon the advice of legal counsel. First Financial had no reserves related to litigation matters as of December 31, 2020 or December 31, 2019.

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
INCOME TAXES	Income Taxes Income tax expense consisted of the following components: (Dollars in thousands) 2020 2019 2018 Current expense Federal $ 34,632 $ 31,343 $ 34,330 State 2,349 854 1,029 Total current expense 36,981 32,197 35,359 Deferred expense (benefit) Federal (8,624) 10,946 4,675 State 244 1,644 1,592 Total deferred expense (benefit) (8,380) 12,590 6,267 Income tax expense $ 28,601 $ 44,787 $ 41,626 The difference between the federal income tax rates applied to income before income taxes and the effective rates were due to the following: (Dollars in thousands) 2020 2019 2018 Income taxes computed at federal statutory rate (21%) on income before income taxes $ 38,726 $ 51,001 $ 44,986 Benefit from tax-exempt income (5,901) (5,964) (4,499) Tax credits (13,064) (10,075) (5,439) Basis reduction on tax credit 657 738 0 Tax expense (benefit) of equity compensation 340 (140) (565) State income taxes, net of federal tax benefit 2,049 1,973 2,070 Affordable housing investments 6,635 5,825 4,725 Other (841) 1,429 348 Income tax expense $ 28,601 $ 44,787 $ 41,626 The major components of the temporary differences that gave rise to deferred tax assets and liabilities at December 31, 2020, and 2019, were as follows: (Dollars in thousands) 2020 2019 Deferred tax assets Allowance for credit losses $ 39,671 $ 13,011 Fair value adjustments on business combinations 3,870 6,470 Deferred compensation 235 228 Postretirement benefits other than pension liability 684 666 Accrued stock-based compensation 1,654 1,296 OREO write-downs 8 162 Interest on nonaccrual loans 1,712 548 Accrued expenses 5,647 4,708 State net operating loss 1,959 2,792 Leasing liability 16,947 14,806 Reserve for unfunded commitments 2,854 133 Deferred loan fees and costs 1,691 0 Other 577 683 Total deferred tax assets 77,509 45,503 Deferred tax liabilities Tax depreciation in excess of book depreciation (11,923) (10,970) FHLB and FRB stock (4,043) (4,043) Mortgage-servicing rights (2,925) (2,435) Leasing activities (6,661) (7,349) Retirement obligation (10,984) (8,511) Intangible assets (13,942) (11,647) Deferred loan fees and costs 0 (1,100) Prepaid expenses (619) (623) Limited partnership investments (2,471) (2,249) Net unrealized gains on investment securities (20,253) (11,359) Foreign exchange deferred income (2,080) (2,845) ASU 2016-01 unrealized gain/loss-equity securities (2,179) (128) Right of use assets (15,053) (13,354) Other (2,035) (1,920) Total deferred tax liabilities (95,168) (78,533) Total net deferred tax liability $ (17,659) $ (33,030) In conjunction with the MSFG merger, First Financial acquired a state net operating loss. At December 31, 2020 and 2019, the state net operating loss carryforward was $2.5 million and $3.6 million. This carryforward begins to expire in 2025. The Company expects to fully utilize this net operating loss and, therefore, a valuation allowance was not required at December 31, 2020 and 2019. The acquired MSFG state net operating loss is subject to IRC Section 382 and is limited annually. The realization of the Company’s deferred tax assets is dependent upon the Company’s ability to generate taxable income in future periods and the reversal of deferred tax liabilities during the same period. The Company has evaluated the available evidence supporting the realization of its deferred tax assets and determined it is more likely than not that the assets will be realized and thus no valuation allowance was recorded at December 31, 2020 and 2019. The Bank’s retained earnings at December 31, 2020 and 2019 included base-year bad debt reserves of $16.1 million as a result of the merger with MSFG. Base-year reserves are subject to recapture in the event the Bank redeems its stock, makes distributions in excess of current and accumulated earnings and profits (as calculated for federal income tax purposes), loses its “bank” status or liquidates. The Bank has no intention of meeting any of the criteria for recapture. Accordingly, a deferred income tax liability of $3.4 million has not been recorded. At December 31, 2020 and 2019, First Financial had $1.9 million and $2.4 million of unrecognized tax benefits, as determined in FASB ASC Topic 740-10, Income Taxes, that, if recognized, would favorably affect the effective income tax rate in future periods. A progression of gross unrecognized tax benefits as of December 31, 2020 and 2019 is as follows: (Dollars in thousands) 2020 2019 Balance at beginning of year $ 3,006 $ 3,735 Settlements (620) (729) Balance at end of year $ 2,386 $ 3,006 The unrecognized tax benefits relate to state income tax exposures where First Financial believes it is likely that, upon examination, a state may take a position contrary to the position taken by the Company. The Company believes that resolution regarding our uncertain tax positions is reasonably possible within the next twelve months and could result in full, partial or no recognition of the benefit. First Financial recognizes interest accrued related to unrecognized tax benefits and penalties as income tax expense. At December 31, 2020 and 2019, the Company had no interest or penalties recorded. First Financial and its subsidiaries are subject to U.S. federal income tax as well as state and local income tax in several jurisdictions. Tax years prior to 2017 have been closed and are no longer subject to U.S. federal income tax examinations. Tax years 2017 through 2020 remain open to examination by the federal taxing authority. First Financial is no longer subject to state and local income tax examinations for years prior to 2012. Tax years 2012 through 2020 remain open to state and local examination by various other jurisdictions.

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLANS	Employee Benefit Plans Pension plan. First Financial sponsors a non-contributory defined benefit pension plan covering substantially all employees and uses a December 31 measurement date for the plan. Plan assets were primarily invested in fixed income and equity mutual funds. The pension plan does not directly own any shares of First Financial common stock or any other First Financial security or product. The investment objective of the Plan is to structure the assets to mirror the liabilities of the Plan, with the fixed income component matching the identified near and long-term plan distributions and the equity component generating growth of capital to meet other future Plan liabilities. The determination of the overall expected long-term return on plan assets was based on the composition of plan assets and a consensus of estimates from similarly managed portfolios of expected future returns. First Financial recorded expense related to its pension plan of $2.5 million for 2020, $1.0 million for 2019 and $0.9 million for 2018. The components of net periodic benefit cost other than the service cost component are included in Other noninterest expense while service costs are recorded as a component Salaries and employee benefits in the Consolidated Statements of Income. First Financial made no cash contributions to the pension plan in 2020, 2019 or 2018 and does not expect to make any contributions in 2020. The following tables set forth information concerning amounts recognized in First Financial's Consolidated Balance Sheets and Consolidated Statements of Income related to the Company's pension plan: December 31, (Dollars in thousands) 2020 2019 Change in benefit obligation Benefit obligation at beginning of year $ 75,044 $ 68,286 Service cost 7,932 6,591 Interest cost 2,455 2,778 Actuarial (gain) loss 9,171 6,848 Benefits paid, excluding settlement (7,108) (9,459) Benefit obligation at end of year 87,494 75,044 Change in plan assets Fair value of plan assets at beginning of year 141,816 130,078 Actual return on plan assets 20,996 21,197 Benefits paid, excluding settlement (7,108) (9,459) Fair value of plan assets at end of year 155,704 141,816 Amounts recognized in the Consolidated Balance Sheets Assets 68,210 66,772 Liabilities 0 0 Net amount recognized $ 68,210 $ 66,772 Amounts recognized in accumulated other comprehensive income (loss) Net actuarial loss $ 32,943 $ 37,278 Net prior service cost (682) (1,095) Deferred tax assets (7,349) (8,242) Net amount recognized $ 24,912 $ 27,941 Change in accumulated other comprehensive income (loss) $ (3,029) $ (4,649) Accumulated benefit obligation $ 86,327 $ 74,424 The changes in the defined benefit obligations for the period were primarily caused by a few factors. The actual return on the fair value of plan assets since the prior measurement date was greater than assumed, which improved the funded position. However, the discount rate declined 78 bp compared to the prior year, causing the funded position to deteriorate. Additionally, the interest crediting rate was updated to reflect the known return during 2020, which resulted in further deterioration of the funded position. The components of net periodic benefit cost are shown in the table that follows: December 31, (Dollars in thousands) 2020 2019 2018 Service cost $ 7,932 $ 6,591 $ 6,501 Interest cost 2,455 2,778 2,394 Expected return on assets (9,824) (9,718) (9,811) Amortization of prior service cost (413) (413) (413) Recognized net actuarial loss 2,334 1,803 2,188 Net periodic benefit (income) cost 2,484 1,041 859 Other changes recognized in accumulated other comprehensive income (loss) Net actuarial (gain) loss (2,001) (4,630) 12,319 Prior service cost 0 0 0 Amortization of prior service cost 413 413 413 Amortization of gain (2,334) (1,803) (2,188) Total recognized in accumulated other comprehensive income (loss) (3,922) (6,020) 10,544 Total recognized in net periodic benefit cost and accumulated other comprehensive income (loss) $ (1,438) $ (4,979) $ 11,403 The pension plan assumptions are shown in the table that follows: December 31, 2020 2019 2018 Benefit obligations Discount rate 2.55 % 3.33 % 4.31 % Rate of compensation increase 3.50 % 3.50 % 3.50 % Weighted average interest crediting rate 2.14 % 2.82 % 3.61 % Net periodic benefit cost Discount rate 3.33 % 4.31 % 3.43 % Expected return on plan assets 7.25 % 7.25 % 7.25 % Rate of compensation increase 3.50 % 3.50 % 3.50 % Weighted average interest crediting rate 2.82 % 3.61 % 2.63 % The fair value of the plan assets as of December 31, 2020 by asset category is shown in the table that follows: Fair Value Measurements (Dollars in thousands) Total Quoted Prices in Significant Significant Asset Category Cash $ 129 $ 129 $ 0 $ 0 U. S. Government agencies 4,193 0 4,193 0 Fixed income mutual funds 65,443 65,443 0 0 Equity mutual funds 85,939 85,939 0 0 Total $ 155,704 $ 151,511 $ 4,193 $ 0 The fair value of the plan assets as of December 31, 2019 by asset category is shown in the table that follows: Fair Value Measurements (Dollars in thousands) Total Quoted Prices in Significant Significant Asset Category Cash $ 195 $ 195 $ 0 $ 0 U. S. Government agencies 5,357 0 5,357 0 Fixed income mutual funds 75,720 75,720 0 0 Equity mutual funds 60,544 60,544 0 0 Total $ 141,816 $ 136,459 $ 5,357 $ 0 The level within the fair value hierarchy is based on the lowest level of input that is significant in the fair value measurement. See Note 22 – Fair Value Disclosures for further information related to the framework for measuring fair value and the fair value hierarchy. The following benefit payments, which reflect expected future service, are expected to be paid: (Dollars in thousands) Expected benefit payments 2021 $ 5,780 2022 5,432 2023 5,474 2024 6,605 2025 6,565 Thereafter 38,095

REVENUE RECOGNITION REVENUE REC

REVENUE RECOGNITION REVENUE RECOGNITION (Notes)	12 Months Ended
	Dec. 31, 2020
Revenue Recognition and Deferred Revenue [Abstract]
REVENUE RECOGNITION	Revenue Recognition On January 1, 2018, the Company adopted ASU No. 2014-09, Revenue from Contracts with Customers using the modified retrospective method applied to all contracts not completed as of January 1, 2018. Results for reporting periods beginning after January 1, 2018 are presented under the guidance set forth in this update while prior period amounts continue to be reported in accordance with legacy GAAP. Adoption of this update did not result in a change to the accounting for any of the in-scope revenue streams. As such, no cumulative effect adjustment to retained earnings was recorded. The majority of the Company's revenues come from sources that are outside of the scope of ASU 2014-09, Revenue from Contracts with Customers. Income sources that are outside of this standard include income earned on loans, leases, securities, derivatives and foreign exchange. The Company's services that fall within the scope of ASU 2019-09 are presented within Noninterest income and are recognized as revenue when the Company satisfies its obligation to the customer. Services within the scope of this guidance include service charges on deposits, trust and wealth management fees, bankcard income, gain/loss on the sale of OREO and investment brokerage fees. Service charges on deposit accounts. The Company earns fees from its deposit customers for transaction-based, account maintenance and overdraft. Transaction-based fees, which include services such as ATM use fees, stop payment charges, statement rendering and ACH fees, are recognized at the time the transaction is executed as that is the point in time the Company fulfills the customer's request. Account maintenance fees, which relate primarily to monthly maintenance, are earned over the course of a month, representing the period over which the Company satisfies the performance obligation. Similarly, overdraft fees are recognized at the point in time that the overdraft occurs as this corresponds with the Company's performance obligation. Service charges on deposit accounts are withdrawn from the customer's account balance. Trust and wealth management fees. Trust and wealth management fees are primarily asset-based, but can also include flat fees based upon a specific service rendered, such as tax preparation services. The Company’s performance obligation is generally satisfied over time and the resulting fees are recognized monthly, based upon the month-end market value of the assets under management and the applicable fees. The Company does not earn performance-based incentives. Optional services such as real estate sales and tax return preparation services are also available to existing trust and wealth management customers. The Company’s performance obligation for these transactional-based services is generally satisfied, and related revenue recognized, as incurred. Bankcard income. The Company earns interchange fees from cardholder transactions conducted through the Visa payment network. Interchange fees from cardholder transactions represent a percentage of the underlying transaction value and are recognized concurrent with the transaction processing services provided to the cardholder. Interchange income is presented on the Consolidated Statements of Income net of expenses. Gross interchange income for 2020 was $23.9 million, and was partially offset by $12.2 million of expenses within Noninterest income. Gross interchange income for 2019 was $30.4 million, and was partially offset by $11.9 million of expenses within Noninterest income, while gross interchange income for 2018 was $31.3 million, and was partially offset by $11.0 million of expenses within Noninterest income. Other. Other noninterest income consists of other recurring revenue streams such as transaction fees, safe deposit rental income, insurance commissions, merchant referral income, gain (loss) on sale of OREO and brokerage revenue. Transaction fees primarily include check printing sales commissions, collection fees and wire transfer fees which arise from in-branch transactions. Safe deposit rental income arises from fees charged to the customer on an annual basis and recognized upon receipt of payment. Insurance commissions are agent commissions earned by the Company and earned upon the effective date of the bound coverage. Merchant referral income is associated with a program whereby the Company receives a share of processing revenue that is generated from clients that were referred by First Financial to the service provider. Revenue is recognized at the point in time when the transaction occurs. The Company records a gain or loss from the sale of OREO when control of the property transfers to the buyer, which generally occurs at the time of the executed deed. When the Company finances the sale of OREO to the buyer, the Company assesses whether the buyer is committed to perform their obligations under the contract and whether collectibility of the transaction price is probable. Once these criteria are met, the OREO asset is derecognized and the gain or loss on sale is recorded upon the transfer of control of the property to the buyer. Brokerage revenue represents fees from investment brokerage services provided to customers by a third party provider. The Company receives commissions from the third-party service provider on a monthly basis based upon customer activity for the month. The fees are recognized monthly and a receivable is recorded until commissions are paid the following month. Because the Company (i) acts as an agent in arranging the relationship between the customer and the third-party service provider and (ii) does not control the services rendered to the customers, investment brokerage fees are presented net of related costs.

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	6 Months Ended
	Jun. 30, 2020
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	Accumulated Other Comprehensive Income (Loss) Shareholders’ equity is affected by transactions and valuations of asset and liability positions that require adjustments to accumulated other comprehensive income (loss). The related tax effects allocated to other comprehensive income and accumulated other comprehensive income (loss) are as follows: December 31, 2020 Total other comprehensive income (loss) Total accumulated (Dollars in thousands) Prior to Reclass Pre-tax Tax effect Net of tax Beginning balance Net activity Ending balance Unrealized gain (loss) on debt securities $ 36,643 $ (4,563) $ 41,206 $ (8,894) $ 32,312 $ 41,264 $ 32,312 $ 73,576 Unrealized gain (loss) on derivatives 0 0 0 0 0 0 0 0 Retirement obligation 2,001 (1,921) 3,922 (893) 3,029 (27,941) 3,029 (24,912) Total $ 38,644 $ (6,484) $ 45,128 $ (9,787) $ 35,341 $ 13,323 $ 35,341 $ 48,664 December 31, 2019 Total other comprehensive income (loss) Total accumulated other (Dollars in thousands) Prior to Reclass Pre-tax Tax-effect Net of tax Beginning Balance Net Activity Cumulative effect of new standard Ending Balance Unrealized gain (loss) on debt securities $ 65,858 $ (370) $ 66,228 $ (14,269) $ 51,959 $ (11,601) $ 51,959 $ 906 $ 41,264 Unrealized gain (loss) on derivatives 281 0 281 (64) 217 (217) 217 0 0 Retirement obligation 4,630 (1,390) 6,020 (1,371) 4,649 (32,590) 4,649 0 (27,941) Total $ 70,769 $ (1,760) $ 72,529 $ (15,704) $ 56,825 $ (44,408) $ 56,825 $ 906 $ 13,323 December 31, 2018 Total other comprehensive income (loss) Total accumulated other (Dollars in thousands) Prior to Reclass Pre-tax Tax-effect Net of tax Beginning Balance Net Activity Cumulative effect of new standard Ending Balance Unrealized gain (loss) on debt securities $ (14,461) $ (161) $ (14,300) $ 3,071 $ (11,229) $ (182) $ (11,229) $ (190) $ (11,601) Unrealized gain (loss) on derivatives 628 0 628 (144) 484 (577) 484 (124) (217) Retirement obligation (12,319) (1,775) (10,544) 2,364 (8,180) (19,631) (8,180) (4,779) (32,590) Total $ (26,152) $ (1,936) $ (24,216) $ 5,291 $ (18,925) $ (20,390) $ (18,925) $ (5,093) $ (44,408) The following table details the activity reclassified from accumulated other comprehensive income into income during the period: Amount Reclassified from Accumulated Other Comprehensive Income (1) December 31, (Dollars in thousands) 2020 2019 2018 Affected Line Item in the Consolidated Statements of Income Realized gains and losses on securities available-for-sale $ (4,563) $ (370) $ (161) Net gain (loss) on sales of investment securities Defined benefit pension plan Amortization of prior service cost (2) 413 413 413 Other noninterest expense Recognized net actuarial loss (2) (2,334) (1,803) (2,188) Other noninterest expense Amortization and settlement charges of defined benefit pension items (1,921) (1,390) (1,775) Total reclassifications for the period, before tax $ (6,484) $ (1,760) $ (1,936) (1) Negative amounts are debits to profit/loss. (2) Included in the computation of net periodic pension cost (see Note 16 - Employee Benefit Plans for additional details).

CAPITAL

CAPITAL	12 Months Ended
	Dec. 31, 2020
Banking Regulation, Total Capital [Abstract]
CAPITAL	Capital Risk-based capital. First Financial and its subsidiary, First Financial Bank, are subject to regulatory capital requirements administered by federal banking agencies. Capital adequacy guidelines and, additionally for banks, prompt corrective action regulations involve quantitative measures of assets, liabilities and certain off-balance sheet items calculated under regulatory accounting practices. Capital amounts and classifications are also subject to qualitative judgments by regulators. Failure to meet minimum capital requirements can initiate regulatory action. The Board of Governors of the Federal Reserve System approved Basel III in order to strengthen the regulatory capital framework for all banking organizations, subject to a phase-in period for certain provisions. Basel III established and defined quantitative measures to ensure capital adequacy. These measures require First Financial to maintain minimum amounts and ratios of Common equity Tier 1 capital, Total and Tier 1 capital to risk-weighted assets and Tier 1 capital to average assets (Leverage ratio). Basel III includes a minimum ratio of Common equity Tier 1 capital to risk-weighted assets of 7.00% and a fully phased-in capital conservation buffer of 2.5% of risk-weighted assets. Further, the minimum ratio of Tier 1 capital to risk-weighted assets increased to 8.5% and all banks are subject to a 4.0% minimum leverage ratio. The required Total risk-based capital ratio is 10.50%. Failure to maintain the required Common equity Tier 1 capital conservation buffer will result in potential restrictions on a bank’s ability to pay dividends, repurchase stock and pay discretionary compensation to its employees. The capital requirements also provide strict eligibility criteria for regulatory capital instruments and change the method for calculating risk-weighted assets in an effort to better identify riskier assets, such as highly volatile commercial real estate and nonaccrual loans. As of December 31, 2020, management believes that First Financial met all capital adequacy requirements to which it was subject. To be categorized as well-capitalized, First Financial must maintain minimum Total risk-based capital, Tier 1 risk-based capital and Tier 1 leverage ratios as set forth in the table that follows. The Company's most recent regulatory notifications categorized First Financial as "well-capitalized" under the regulatory framework for prompt corrective action. There have been no conditions or events since those notifications that management believes have changed the Company's categorization. Total regulatory capital exceeded the minimum requirement by $566.8 million on a consolidated basis at December 31, 2020. The following tables present the actual and required capital amounts and ratios as of December 31, 2020 and 2019 under the Basel III Capital Rules. The minimum required capital amounts presented include the minimum required capital levels based on the phase-in provisions of the Basel III Capital Rules as of the year presented. Capital levels required to be considered "well capitalized" are based upon prompt corrective action regulations, as amended to reflect the changes under the Basel III Capital Rules. Actual Minimum capital PCA requirement to be (Dollars in thousands) Capital Ratio Capital Ratio Capital Ratio December 31, 2020 Common equity tier 1 capital to risk-weighted assets Consolidated $ 1,325,922 11.82 % $ 785,338 7.00 % N/A N/A First Financial Bank 1,452,403 12.95 % 784,807 7.00 % $ 728,749 6.50 % Tier 1 capital to risk-weighted assets Consolidated 1,368,818 12.20 % 953,625 8.50 % N/A N/A First Financial Bank 1,452,507 12.96 % 952,980 8.50 % 896,922 8.00 % Total capital to risk-weighted assets Consolidated 1,744,802 15.55 % 1,178,007 10.50 % N/A N/A First Financial Bank 1,560,457 13.92 % 1,177,211 10.50 % 1,121,153 10.00 % Leverage Consolidated 1,368,818 9.55 % 573,526 4.00 % N/A N/A First Financial Bank 1,452,507 10.14 % 573,094 4.00 % 716,367 5.00 % Actual Minimum capital PCA requirement to be (Dollars in thousands) Capital Ratio Capital Ratio Capital Ratio December 31, 2019 Common equity tier 1 capital to risk-weighted assets Consolidated $ 1,245,746 11.30 % $ 771,666 7.00 % N/A N/A First Financial Bank 1,333,978 12.11 % 770,997 7.00 % $ 715,926 6.50 % Tier 1 capital to risk-weighted assets Consolidated 1,288,185 11.69 % 937,023 8.50 % N/A N/A First Financial Bank 1,334,082 12.11 % 936,211 8.50 % 881,140 8.00 % Total capital to risk-weighted assets Consolidated 1,475,813 13.39 % 1,157,498 10.50 % N/A N/A First Financial Bank 1,399,817 12.71 % 1,156,496 10.50 % 1,101,425 10.00 % Leverage Consolidated 1,288,185 9.58 % 537,606 4.00 % N/A N/A First Financial Bank 1,334,082 9.93 % 537,299 4.00 % 671,623 5.00 % Share repurchases. In December 2020, First Financial's board of directors approved a stock repurchase plan, replacing the plan approved in 2019 which expired on December 31, 2020. The plan approved in 2020 will continue for two years and like the 2019 plan, authorizes the purchase of up to 5,000,000 shares of the Company's common stock. Under the 2019 plan, First Financial repurchased 880,000 shares at an average market price of $18.96 during 2020 and repurchased 2,753,272 shares at an average market price of $24.05 during 2019. Prior to the 2019 plan's expiration on December 31, 2020, it had 1,366,728 common shares available for repurchase. There were no share repurchases in 2018. ATM Offering. In March 2017, First Financial initiated an "at-the-market" equity offering program to provide flexibility with respect to capital planning and to support future growth. First Financial was not active through the ATM program during the periods presented.

STOCK OPTIONS AND AWARDS

STOCK OPTIONS AND AWARDS	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
STOCK OPTIONS AND AWARDS	Stock Options and Awards First Financial follows the provisions of FASB ASC Topic 718, Compensation-Stock Compensation, which requires measurement of compensation cost for all stock-based awards at fair value on the date of grant and recognition of compensation expense over the service period for all awards expected to vest. First Financial recorded share-based compensation expense within salaries and employee benefits on the Consolidated Statements of Income of $7.7 million, $8.0 million and $6.2 million for the years ended December 31, 2020, 2019 and 2018, respectively, related to stock options and restricted stock awards. Total unrecognized compensation cost related to non-vested share-based compensation was $9.1 million at December 31, 2020 and is expected to be recognized over a weighted average period of 1.92 years. As of December 31, 2020, First Financial had two active stock-based compensation plans, the Amended and Restated 2012 Stock Plan and the 2020 Stock Plan. New awards may only be granted from the 2020 Stock Plan. At December 31, 2020, there were 4,311,365 shares available for issuance under the 2020 Stock Plan. In April 2018, in conjunction with the MSFG merger, First Financial assumed existing MSFG stock options, which were converted into options to purchase 83,551 shares of First Financial common stock. The converted MSFG options remain subject to all of the terms and conditions of the plan and grant agreements under which the MSFG Stock Options were originally issued. The assumed options were exercisable at the time of the merger and remain outstanding for 10 years after the initial grant date with all options expiring at the end of the exercise period. At December 31, 2020, 27,451 options were outstanding under the Plan, all of which expire on or before February 3, 2024. First Financial utilizes the Black-Scholes valuation model to determine the fair value of stock options granted. In addition to the stock option strike price, the Black-Scholes valuation model incorporates the following assumptions: the expected dividend yield based on historical dividend payouts; the expected stock price volatility based on the historical volatility of Company stock for a period approximating the expected life of the options; the risk-free rate based on the U.S. Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option; and the expected option life represented by the period of time the options are expected to be outstanding, and is based on historical trends. No new options were granted in 2020, 2019 or 2018. Stock option activity for the year ended December 31, 2020, is summarized as follows: (Dollars in thousands, except share and per share data) Number of shares Weighted Weighted average Aggregate intrinsic value Outstanding at beginning of year 37,856 $ 9.54 Granted 0 0.00 Exercised (10,405) 6.92 Forfeited or expired 0 0.00 Outstanding at end of year 27,451 $ 10.53 2.53 years $ 192 Exercisable at end of year 27,451 $ 10.53 2.53 years $ 192 The intrinsic value of stock options is defined as the difference between the current market value and the exercise price. First Financial uses treasury shares purchased under the Company's share repurchase program to satisfy share-based exercises. 2020 2019 2018 Total intrinsic value of options exercised $ 86 $ 462 $ 734 Cash received from exercises $ 72 $ 90 $ 284 Tax benefit from exercises $ 1,776 $ 1,844 $ 1,439 Restricted stock awards are recorded at fair value as of the grant date as a component of shareholders' equity and amortized on a straight-line basis to salaries and benefits expense over the specified vesting periods, which is currently three years for employees and one year for non-employee directors. The vesting of these awards for employees and non-employee directors may require a service period to be met, and certain awards may also require performance measures to be met. Activity in restricted stock for the previous three years ended December 31 is summarized as follows: 2020 2019 2018 Number of shares Weighted Number of shares Weighted Number of shares Weighted Nonvested at beginning of year 530,569 $ 27.19 462,446 $ 26.39 468,372 $ 21.63 Granted 503,311 18.62 395,023 26.55 303,930 28.94 Vested (233,828) 26.07 (295,633) 24.94 (267,031) 20.94 Forfeited (36,769) 23.79 (31,267) 28.63 (42,825) 26.38 Nonvested at end of year 763,283 $ 22.04 530,569 $ 27.19 462,446 $ 26.39 The fair value of restricted stock is determined based on the number of shares granted and the quoted price of First Financial's common stock. The fair value of restricted stock vested during 2020, 2019 and 2018 was $6.1 million, $7.4 million and $5.6 million, respectively.

EARNINGS PER COMMON SHARE

EARNINGS PER COMMON SHARE	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
EARNINGS PER COMMON SHARE	Earnings per Common Share The following table sets forth the computation of basic and diluted earnings per share: (Dollars in thousands, except share and per share data) 2020 2019 2018 Numerator Net income $ 155,810 $ 198,075 $ 172,595 Denominator Basic earnings per common share - weighted average shares 97,363,952 98,305,570 88,582,090 Effect of dilutive securities Employee stock awards 729,146 545,901 514,680 Warrants 0 0 517,435 Diluted earnings per common share - adjusted weighted average shares 98,093,098 98,851,471 89,614,205 Earnings per share available to common shareholders Basic $ 1.60 $ 2.01 $ 1.95 Diluted $ 1.59 $ 2.00 $ 1.93 First Financial had no warrants outstanding to purchase the Company's common stock as of December 31, 2020 or 2019. Warrants acquired in the MSFG merger were outstanding as of December 31, 2018 and represented the right to purchase 804,858 shares of First Financial's common stock at an exercise price of $10.62 per share. These warrants were exercised in January 2019. If applicable, stock options and warrants with exercise prices greater than the average market price of the common shares are excluded from the computation of net income per diluted share, as they would be antidilutive. Using the end of period price of the Company's common shares, there were no antidilutive options at December 31, 2020, 2019, or 2018.

FAIR VALUE DISCLOSURES

FAIR VALUE DISCLOSURES	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
FAIR VALUE DISCLOSURES	Fair Value Disclosures The fair value framework as disclosed in the Fair Value Topic includes a hierarchy which focuses on prioritizing the inputs used in valuation techniques. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1), a lower priority to observable inputs other than quoted prices in active markets for identical assets and liabilities (Level 2) and the lowest priority to unobservable inputs (Level 3). When determining the fair value measurements for assets and liabilities, First Financial looks to active markets to price identical assets or liabilities whenever possible and classifies such items in Level 1. When identical assets and liabilities are not traded in active markets, First Financial looks to observable market data for similar assets and liabilities and classifies such items as Level 2. Certain assets and liabilities are not actively traded in observable markets and First Financial must use alternative techniques, based on unobservable inputs, to determine the fair value and classifies such items as Level 3. The level within the fair value hierarchy is based on the lowest level of input that is significant in the fair value measurement. The estimated fair values of First Financial's financial instruments not measured at fair value on a recurring or nonrecurring basis in the consolidated financial statements were as follows: Carrying Estimated fair value (Dollars in thousands) value Total Level 1 Level 2 Level 3 December 31, 2020 Financial assets Cash and short-term investments $ 251,359 $ 251,359 $ 251,359 $ 0 $ 0 Investment securities held-to-maturity 131,687 136,698 0 136,698 0 Other investments 133,198 133,198 837 122,953 9,408 Loans and leases 9,725,291 9,743,497 0 0 9,743,497 Accrued interest receivable 50,903 50,903 0 13,221 37,682 Financial liabilities Deposits 12,232,003 12,238,058 0 12,238,058 0 Short-term borrowings 166,594 166,594 166,594 0 0 Long-term debt 776,202 774,674 0 774,674 0 Accrued interest payable 6,240 6,240 14 6,226 0 Carrying Estimated Fair Value (Dollars in thousands) Value Total Level 1 Level 2 Level 3 December 31, 2019 Financial assets Cash and short-term investments $ 257,639 $ 257,639 $ 257,639 $ 0 $ 0 Investment securities held-to-maturity 142,862 142,821 0 142,821 0 Other investments 125,020 125,020 699 123,821 500 Loans and leases 9,144,015 9,134,215 0 0 9,134,215 Accrued interest receivable 39,591 39,591 0 12,743 26,848 Financial liabilities Deposits 10,210,229 10,209,790 0 10,209,790 0 Short-term borrowings 1,316,181 1,316,181 1,316,181 0 0 Long-term debt 414,376 414,937 0 414,937 0 Accrued interest payable 13,671 13,671 1,899 11,772 0 The following methods, assumptions and valuation techniques were used by First Financial to measure different financial assets and liabilities at fair value on a recurring or nonrecurring basis. Investment securities. Investment securities classified as available-for-sale are recorded at fair value on a recurring basis. Fair value measurement is based upon quoted market prices, when available (Level 1). If quoted market prices are not available, fair values are measured utilizing independent valuation techniques of identical or similar investment securities. First Financial compiles prices from various sources who may apply such techniques as matrix pricing to determine the value of identical or similar investment securities (Level 2). Matrix pricing is a mathematical technique widely used in the banking industry to value investment securities without relying exclusively on quoted prices for the specific investment securities but rather relying on the investment securities’ relationship to other benchmark quoted investment securities. Any investment securities not valued based upon the methods previously described are considered Level 3. First Financial utilizes values provided by third-party pricing vendors to price the investment securities portfolio in accordance with the fair value hierarchy of the Fair Value Topic and reviews the pricing methodologies utilized by the pricing vendors to ensure that the fair value determination is consistent with the applicable accounting guidance. First Financial’s pricing process includes a series of quality assurance activities where prices are compared to recent market conditions, historical prices and other independent pricing services. Further, the Company periodically validates the fair value of a sample of securities in the portfolio by comparing the fair values to prices from other independent sources for the same or similar securities. First Financial analyzes unusual or significant variances, conducts additional research with the pricing vendor, and if necessary, takes appropriate action based on its findings. The results of the quality assurance process are incorporated into the selection of pricing providers by the portfolio manager. Loans held for sale. The fair value of the Company’s residential mortgage loans held for sale is determined on a recurring basis based on quoted prices for similar loans in active markets, and therefore, is classified as a Level 2 measurement. Derivatives. The fair values of derivative instruments are based primarily on a net present value calculation of the cash flows related to the interest rate swaps and foreign exchange contracts at the reporting date, using primarily observable market inputs such as interest rate yield curves and currency exchange rates, which represents the cost to terminate the swap if First Financial should choose to do so. Additionally, First Financial utilizes an internally-developed model to value the credit risk component of derivative assets and liabilities, which is recorded as an adjustment to the fair value of the derivative asset or liability on the reporting date. Derivative instruments are classified as Level 2 in the fair value hierarchy. Collateral dependent loans. Collateral dependent loans carried at fair value have been partially charged-off or receive specific allocations of the allowance for credit losses. For collateral dependent loans, fair value is generally based on real estate appraisals, a calculation of enterprise value or a valuation of business assets including equipment, inventory and accounts receivable. These loans had a principal amount of $45.3 million, with a valuation allowance of $13.5 million at December 31, 2020. The value of real estate collateral is determined utilizing an income or market valuation approach based on an appraisal conducted by an independent, licensed third-party appraiser (Level 3). These appraisals may utilize a single valuation approach or a combination of approaches including the comparable sales approach and the income approach. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between the comparable sales and income data available. Collateral is then adjusted or discounted based on management’s historical knowledge, changes in market conditions from the time of the valuation, and management’s expertise and knowledge of the client and the client’s business, resulting in a Level 3 fair value classification. Collateral dependent loans are evaluated on a quarterly basis for additional write-downs and are adjusted accordingly. Enterprise value is defined as imputed value for the entire underlying business. To determine an appropriate range of enterprise value, FFB relies on a standardized set of valuation methodologies that take into account future projected cash flows, market based multiples as well as asset values. Valuations involve both quantitative and qualitative considerations and professional judgments concerning differences in financial and operating characteristics in addition to other factors that may impact values over time (Level 3). The value of business equipment is based on an outside appraisal, if deemed significant, or the net book value on the applicable borrower financial statements. Likewise, values for inventory and accounts receivable collateral are based on borrower financial statement balances or aging reports on a discounted basis as appropriate (Level 3). The fair value of collateral dependent loans is measured at fair value on a nonrecurring basis. Any fair value adjustments are recorded in the period incurred as provision for credit losses on the Consolidated Statements of Income. OREO. Assets acquired through loan foreclosure are recorded at fair value less costs to sell, with any difference between the fair value of the property and the carrying value of the loan recorded as a charge-off. If the fair value is higher than the carrying amount of the loan, the excess is recognized first as a recovery and then as noninterest income. Subsequent declines in value are reported as adjustments to the carrying amount and are recorded in noninterest expense. The carrying value of OREO is not re-measured to fair value on a recurring basis, but is subject to fair value adjustments when the carrying value differs from the fair value, less estimated selling costs. Fair value is based on recent real estate appraisals and is updated at least annually. The Company classifies OREO in level 3 of the fair value hierarchy. The financial assets and liabilities measured at fair value on a recurring basis, including those for which we elected the fair value option, were as follows: Fair Value Measurements Using Assets/Liabilities (Dollars in thousands) Level 1 Level 2 Level 3 at Fair Value December 31, 2020 Assets Investment securities available-for-sale $ 103 $ 3,383,902 $ 40,575 $ 3,424,580 Loans held for sale 0 41,103 0 41,103 Interest rate derivative contracts 0 185,032 0 185,032 Foreign exchange derivative contracts 0 87,615 0 87,615 Total $ 103 $ 3,697,652 $ 40,575 $ 3,738,330 Liabilities Interest rate derivative contracts $ 0 $ 186,124 $ 0 $ 186,124 Foreign exchange derivative contracts 0 87,615 0 87,615 Total $ 0 $ 273,739 $ 0 $ 273,739 Fair Value Measurements Using Assets/Liabilities (Dollars in thousands) Level 1 Level 2 Level 3 at Fair Value December 31, 2019 Assets Investment securities available-for-sale $ 100 $ 2,842,794 $ 9,190 $ 2,852,084 Loans held for sale 0 13,680 0 13,680 Interest rate derivative contracts 0 73,558 0 73,558 Foreign exchange derivative contracts 0 39,172 0 39,172 Total $ 100 $ 2,969,204 $ 9,190 $ 2,978,494 Liabilities Interest rate derivative contracts $ 0 $ 73,750 $ 0 $ 73,750 Foreign exchange derivative contracts 0 39,172 0 39,172 Total $ 0 $ 112,922 $ 0 $ 112,922 The following table presents a reconciliation for certain AFS securities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the year ended December 31, 2020. (dollars in thousands) December 31, 2020 December 31, 2019 Beginning balance $ 9,190 $ 14,715 Accretion (amortization) 1 (552) Increase (decrease) in fair value (17) 30 Purchases (settlements) 31,401 (5,003) Ending balance $ 40,575 $ 9,190 Certain financial assets and liabilities are measured at fair value on a nonrecurring basis. Adjustments to the fair market value of these assets usually result from the application of fair value accounting or write-downs of individual assets. The following table summarizes financial assets and liabilities measured at fair value on a nonrecurring basis: Fair Value Measurements Using (Dollars in thousands) Level 1 Level 2 Level 3 December 31, 2020 Assets Collateral dependent loans Commercial $ 0 $ 0 $ 25,367 Commercial real estate 0 0 6,432 OREO 0 0 54 Fair Value Measurements Using (Dollars in thousands) Level 1 Level 2 Level 3 December 31, 2019 Assets Collateral dependent loans Commercial $ 0 $ 0 $ 8,710 Commercial real estate 0 0 558 OREO 0 0 1,088

BUSINESS COMBINATIONS

BUSINESS COMBINATIONS	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
BUSINESS COMBINATIONS	Business Combination In August, 2019, the Company completed its acquisition of Bannockburn Global Forex, LLC. Pursuant to the acquisition agreement, First Financial agreed to acquire all of the issued and outstanding membership interests of BGF for aggregate consideration of approximately $114.6 million consisting of $53.7 million in cash and $60.9 million of First Financial common stock. BGF was a privately held capital markets trading firm specializing in foreign currency advisory, hedge analytics and transaction processing for closely held enterprises. Upon completion of the transaction, Bannockburn became a division of the Bank, but continues to operate as Bannockburn Global Forex, taking advantage of its existing brand recognition within the foreign exchange industry. The Bannockburn 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 in accordance with FASB ASC Topic 805, Business Combinations. The fair value measurements of assets acquired and liabilities assumed were $74.9 million and $18.4 million, respectively, and were subject to refinement for up to one year after the closing date of the acquisition as additional information relative to closing date fair values became available. The fair value of assets acquired and liabilities assumed were considered final as of August 2020. Goodwill arising from the BGF acquisition was $58.0 million and reflects the business’s high growth potential and the expectation that the acquisition will provide additional revenue growth and diversification. The goodwill is deductible for income tax purposes as the transaction is considered a taxable exchange. For further detail, see Note 9 – Goodwill and Other Intangible Assets. In April 2018, First Financial completed its acquisition of MainSource Financial Group, Inc. and its banking subsidiary, MainSource Bank. Under the terms of the merger agreement, shareholders of MSFG received 1.3875 common shares of First Financial common stock for each share of MSFG common stock, with cash paid in lieu of fractional shares. Including outstanding options and warrants to purchase MSFG common stock, the total purchase consideration was $1.1 billion and resulted in goodwill of $675.6 million. The goodwill arising from the acquisition largely reflected synergies and cost savings resulting from combining the operations of the companies. First Financial incurred merger related expenses related to the MSFG acquisition of $3.2 million and $37.8 million during the years ended December 31, 2019 and 2018, respectively. The MSFG acquisition provided additional revenue growth and diversification. The goodwill is not deductible for income tax purposes as the transaction was accounted for as a tax-free exchange. For further detail, see Note 9 – Goodwill and Other Intangible Assets. The MainSource 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, in accordance with FASB ASC Topic 805, Business Combinations. The fair value measurements of assets acquired and liabilities assumed were subject to refinement for up to one year after the closing date of the acquisition as additional information relative to closing date fair values became available. The fair values of assets acquired and liabilities assumed were considered final as of March 31, 2019. The following table provides the purchase price calculation as of the acquisition date, identifiable assets purchased and liabilities assumed at their estimated fair value for the MSFG merger. As a condition of the merger, certain acquired assets and liabilities held for sale were divested subsequent to the closing of the merger. There was no gain or loss recorded in the Consolidated Statement of Income in conjunction with this divestiture. (Dollars in thousands) MainSource Purchase consideration Cash consideration $ 43 Stock consideration 1,043,424 Warrant consideration 14,460 Options consideration 1,577 Total purchase consideration 1,059,504 Assets acquired Cash 71,806 Investment securities available-for-sale 900,935 Investment securities held-to-maturity 171,423 Other investments 28,763 Loans 2,792,572 Premises and equipment 98,814 Intangible assets 42,887 Other assets 167,829 Assets held for sale 127,775 Total assets acquired 4,402,804 Liabilities assumed Deposits 3,263,920 Subordinated notes 49,027 FHLB advances 291,887 Other borrowings 205,620 Other liabilities 32,649 Liabilities held for sale 175,840 Total liabilities assumed 4,018,943 Net identifiable assets 383,861 Goodwill $ 675,643 The fair value of net assets acquired includes fair value adjustments to certain loans that were not considered impaired as of the acquisition date as the Company believes that all contractual cash flows will be collected. The fair value adjustments were determined using discounted cash flows. In conjunction with the MSFG merger, First Financial acquired non-impaired loans with a fair value and gross contractual amounts receivable of $2.8 billion and $2.9 billion, respectively. The following table presents supplemental pro forma information as if the MSFG acquisition had occurred at the beginning of 2017. The pro forma information includes adjustments for interest income on acquired loans, amortization of intangible assets arising from the transaction, depreciation expense on property acquired, interest expense on deposits acquired, merger-related expenses incurred and the related income tax effects. The pro forma financial information is not necessarily indicative of the results of operations that would have occurred had the transactions been effected on the assumed date. The disclosures regarding the results of operations for MSFG subsequent to its acquisition date are omitted as this information is not practical to obtain. Twelve months ended December 31, (Dollars in thousands, except per share data) (Unaudited) 2018 2017 Pro Forma Condensed Combined Income Statement Information Net interest income $ 484,915 $ 454,579 Net income $ 221,122 $ 130,402 Basic earnings per share $ 2.27 $ 1.34 Diluted earnings per share $ 2.25 $ 1.33

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2020
Basis of Presentation Policy	Basis of presentation. The Consolidated Financial Statements of First Financial Bancorp., a financial holding company, principally serving Ohio, Indiana, Kentucky and Illinois, include the accounts and operations of First Financial and its wholly owned subsidiary, First Financial Bank. All significant intercompany transactions and accounts have been eliminated in consolidation. Certain reclassifications of prior years' amounts have been made to conform to current year presentation. Such reclassifications had no effect on net earnings.
Use of Estimates, Policy	Use of estimates. The preparation of financial statements in conformity with GAAP requires management to make estimates, assumptions and judgments that affect the amounts reported in the Consolidated Financial Statements and accompanying Notes. These estimates, assumptions and judgments are inherently subjective and my Actual realized amounts could differ materially from those estimates. COVID-19. In the majority of 2020, First Financial's operations and financial results were significantly impacted by the COVID-19 pandemic. The spread of COVID-19 has caused significant economic disruption throughout the United States as state and local governments issued stay at home orders and temporarily closed non-essential businesses. The full financial impact from the pandemic is unknown at this time, however prolonged disruption may adversely impact several industries within the Company's geographic footprint and impair the ability of First Financial's customers to fulfill their contractual obligations to the Company. This could cause First Financial to experience a material adverse effect on business operations, asset valuations, financial condition and results of operations. Material adverse impacts may include all or a combination of valuation impairments on First Financial's intangible assets, investments, loans, mortgage servicing rights or counter-party risk derivatives.
Cash and Cash Equivalents, Policy	Cash and due from banks. Cash and due from banks consist of currency, coin and cash items due from banks. Cash items due from banks include noninterest-bearing balances that are on deposit at other depository institutions.
Investment, Policy	Investment securities. First Financial classifies debt securities into three categories: HTM, trading and AFS. Management classifies investment securities into the appropriate category at the time of purchase and re-evaluates that classification as deemed appropriate. Investment securities are classified as HTM when First Financial has the positive intent and ability to hold the securities to maturity. HTM securities are recorded at amortized cost. Investment securities classified as trading are held principally for resale in the near-term and are recorded at fair value. Fair value is determined using quoted market prices. Gains or losses on trading securities, both realized and unrealized, are reported in noninterest income. Investment securities not classified as either HTM or trading are classified as AFS. AFS securities are recorded at fair value, with the unrealized gains and losses, net of tax, reported as a separate component of accumulated other comprehensive income (loss) in shareholders' equity. The amortized cost of investment securities classified as either HTM or AFS is adjusted for amortization of premiums and accretion of discounts to maturity, or in the case of mortgage-backed securities, over the estimated life of the security. Such amortization and accretion are considered an adjustment to the yield on the security and included in interest income from investments. Interest and dividends are also included in interest income from investment securities in the Consolidated Statements of Income. Realized gains and losses are based on the amortized cost of the security sold using the specific identification method. Other investments. Other investments include holdings in FRB and FHLB stock, which are both carried at cost as well as equity securities, including class B Visa shares which are carried at fair value. Changes in the fair value of equity securities are recorded in Unrealized gain (loss) on securities in the Consolidated Statements of Income.
Financing Receivable, Held-for-sale [Policy Text Block]	Loans held for sale. Loans held for sale consist of residential real estate loans newly originated for the purpose of sale to third parties, and in certain circumstances, loans previously originated that have been specifically identified by management for sale based on predetermined criteria. Loans held for sale are carried at fair value. Any subsequent change in the carrying value of
Finance, Loans and Leases Receivable, Policy	Loans and leases. Loans and leases for which First Financial has the intent and ability to hold for the foreseeable future, or until maturity or payoff, are classified in the Consolidated Balance Sheets as loans and leases. Loans and leases are carried at the principal amount outstanding, net of unamortized deferred loan origination fees and costs, and net of unearned income. Loan origination and commitment fees received, as well as certain direct loan origination costs paid, are deferred, and the net amount is amortized as an adjustment to the related loan's yield. Interest income on loans and leases is recorded on an accrual basis. When a loan is classified as nonaccrual, the accrual of interest income is discontinued and previously accrued, but unpaid interest is reversed. Any payments received while a loan is classified as nonaccrual are applied as a reduction to the carrying value of the loan. A loan may return to accrual status if collection of future principal and interest payments is no longer doubtful.
Credit Loss, Financial Instrument	Allowance for credit losses - held-to-maturity securities . Management measures expected credit losses on held-to-maturity debt securities on a collective basis by security type. The estimate of expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Management classifies the held-to-maturity portfolio into the following major security types: Mortgage-backed, CMOs and Obligations of state and other political subdivisions. Nearly all of the HTM securities held by the Company are issued by U.S. government entities and agencies. These securities are either explicitly or implicitly guaranteed by the U.S. government, are highly rated by major rating agencies and have a long history of no credit losses. The remainder of the Company's HTM securities are non-agency collateralized mortgage obligations and obligations of state and other political subdivisions which currently carry ratings no lower than A+. Accrued interest receivable on held-to maturity debt securities, which totaled $0.3 million as of December 31, 2020, is excluded by policy election from the estimate of credit losses. Allowance for credit losses - available-for-sale securities. For available-for-sale debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For debt securities available-for-sale that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that has not been recorded through an allowance for credit loss is recognized in other comprehensive income. Changes in the allowance for credit losses are recorded as provision for credit loss expense. Losses are charged against the allowance when management believes the uncollectibility of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. Accrued interest receivable on available-for-sale debt securities, which totaled $12.9 million as of December 31, 2020, is excluded from the estimate of credit losses.
Loans and Leases Receivable, Allowance for Loan Losses Policy	Allowance for credit losses - loans and leases. T he allowance for credit losses is a valuation account that is deducted from the loans’ amortized cost basis to present the net amount expected to be collected on the loans. Management's determination of the adequacy of the ACL is based on an assessment of the expected credit losses on loan and leases over the expected life of the loan. The ACL is increased by provision expense and decreased by charge-offs, net of recoveries of amounts previously charged-off. Loans are charged off when management believes that the collection of the princ ipal amount owed in full, either through payments from the borrower or a guarantor or from the liquidation of collateral, is unlikely. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged-off. Any interest that is accrued bu t not collected is reversed against interest income when a loan is placed on nonaccrual status, which typically occurs prior to charging off all, or a portion, of a loan. The Company made the policy election to exclude accrued interest receivable on loans and leases from the estimate of credit losses. Management estimates the allowance balance using relevant available information from both internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience paired with economic forecasts provide the basis for the quantitatively modeled estimation of expected credit losses. First Financial adjusts its quantitative model, as necessary, to reflect conditions not already considered by the quantitative model. These adjustments are commonly known as the Qualitative Framework. First Financial quantitatively models expected credit loss using PD, LGD and EAD over the R&S forecast period, reversion and post-reversion periods. Utilizing third-party software, the Bank forecasts PD by using a parameterized transition matrix approach. Average transition matrices are calculated over the TTC period, which was defined as the period from December 2007 to December 2016. TTC transition matrices are adjusted under forward-looking macroeconomic expectations to obtain R&S forecasts. First Financial is not required to develop forecasts over full the contractual term of the financial asset or group of financial assets. Rather, for periods beyond which the entity is able to make or obtain R&S forecasts of expected credit losses, the Company reverts in a straight line manner over a one year period to an average TTC loss level that is reflective of the prepayment adjusted contractual term of the financial asset or group of financial assets. The R&S period, elected by the bank to be two years, is forecasted using econometric data sourced from Moody's, an industry-leading independent third party. FFB utilizes a non-parametric loss curve approach embedded within a third-party software for estimating LGD. The PD multiplied by LGD produces an expected loss rate that, when calculating the ACL, is applied to contractual loan cash flows, adjusted for expected future rates of principal prepayments. The Company adjusts its quantitative model for certain qualitative factors to reflect the extent to which management expects current conditions and R&S forecasts to differ from the conditions that existed for the period over which historical information was evaluated. The Qualitative Framework reflects changes related to relevant data, such as changes in asset quality trends, portfolio growth and composition, national and local economic factors, credit policy and administration and other factors not considered in the base quantitative model. Loans that do not share risk characteristics are evaluated on an individual basis. First Financial will typically evaluate on an individual basis any loans that are on nonaccrual, designated as a TDR, or reasonably expected to be designated as a TDR. When management determines that foreclosure is probable or when repayment is expected to be provided substantially through the operation or sale of underlying collateral, expected credit losses are based on the fair value of the collateral at the reporting date, adjusted for selling costs. For loans evaluated on an individual basis that are not determined to be collateral dependent, a discounted cash flow analysis is performed to determine expected credit losses. Expected credit losses are estimated over the contractual term of the loans, adjusted for expected prepayments when appropriate. The contractual term excludes expected extensions, renewals and modifications unless either of the following applies: management has a reasonable expectation at the reporting date that a troubled debt restructuring will be executed with an individual borrower or the extension or renewal options are included in the original or modified contract at the reporting date and are not unconditionally cancellable by the Company. Credit card receivables do not have stated maturities. In determining the estimated life of a credit card receivable, management first estimates the future cash flows expected to be received and then applies those expected future cash flows to the credit card balance.
Commitments and Contingencies, Policy	Allowance for credit losses - unfunded commitments . Effective January 1, 2020, First Financial adopted ASC 326, at which time First Financial estimated expected credit losses over the contractual period in which the Company is exposed to credit risk via a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by the Company. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on commitments expected to be funded over its estimated life consistent with the Company's ACL methodology for loans and leases. A djustments to the reserve for unfunded commitments are recorded in Provision for credit losses - unfunded commitments in the Consolidated Statements of Income. The reserve for unfunded commitments is included in Accrued interest and other liabilities on the Consolidated Balance Sheets. Prior to the adoption of ASC 326, First Financial maintained its reserve to absorb probable losses incurred in standby letters of credit and outstanding loan commitments. First Financial determined the adequacy of this reserve based upon an evaluation of the unfunded credit facilities, which included consideration of historical commitment utilization experience, credit risk ratings and historical loss rates, consistent with the Company's ALLL methodology at the time. First Financial offers a variety of financial instruments including letters of credit and outstanding commitments to extend credit to assist clients in meeting their requirement for liquidity and credit enhancement. GAAP does not require these financial instruments to be recorded in the Consolidated Financial Statements. First Financial utilizes the same credit policies in issuing commitments and conditional obligations as it does for credit instruments recorded on the Consolidated Balance Sheets. First Financial’s exposure to credit loss in the event of nonperformance by the counterparty was represented by the contractual amounts of those instruments. Effective January 1, 2020, First Financial adopted ASC 326, at which time First Financial estimated credit losses over the contractual period in
Property, Plant and Equipment, Policy	Premises and equipment. Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation and amortization are principally computed on the straight-line method over the estimated useful lives of the assets. Useful lives generally range from 10 to 40 years for building and building improvements; 3 to 10 years for furniture, fixtures
Bank Owned Life Insurance [Policy Text Block]	Bank-owned life insurance. First Financial purchases life insurance policies on the lives of certain employees and is the owner and beneficiary of the policies. The Bank invests in these policies to provide an efficient form of funding for long-term retirement and other employee benefits costs. The policies are included within Accrued interest and other assets in the Consolidated Balance Sheets at each policy’s respective cash surrender value with changes recorded in Other noninterest income in the Consolidated Statements of Income.
Goodwill and Intangible Assets, Goodwill, Policy	Goodwill. Under accounting for business combinations, the net assets of entities acquired by First Financial are recorded at their estimated fair value at the date of acquisition. The excess cost of the acquisition over the fair value of net assets acquired is recorded as goodwill. Goodwill and other intangible assets deemed to have indefinite lives are not amortized, but are subject to annual impairment tests. The Company is required to evaluate goodwill for impairment on an annual basis or whenever events or changes in circumstances indicate that the carrying value may not be recoverable. First Financial performs its annual impairment test effective October 1, absent events or changes in circumstances that indicate the carrying value of goodwill may not be recoverable. Goodwill is evaluated for impairment on an annual basis as of October 1 of each year, or whenever events or changes in circumstances indicate that the fair value of a reporting unit may be below its carrying value. First Financial engaged a third party to perform a quantitative analysis of its goodwill to determine whether any impairment existed as of October 1, 2020 for its annual impairment test. This quantitative analysis was performed due to the on-going economic market disruption, the movement of the Company’s stock price in relation to other bank indexes and the length of time that the market value of the reporting unit had been below its book value. This analysis indicated that no impairment existed as of the issue date. Our quantitative impairment analysis utilized the discounted cash flow model for the income approach and the market multiple methodology and comparable transaction methodology as the market approach. These valuation methodologies utilize key assumptions that include forecasts of revenues and expenses derived from internal management projections for a period of five years, changes in working capital estimates, company specific discount rate derived from a rate build up approach, externally sourced bank peer group market multiples and externally sourced bank peer group change in control premium, all of which are highly subjective and require significant management judgment. Changes in these key assumptions could materially affect our estimate of the reporting unit fair value and could affect our conclusion regarding the existence of potential impairment. Additionally, in response to the COVID-19 pandemic and the related deterioration in general economic conditions, First Financial performed an interim qualitative impairment test as of the end of each quarter in 2020, including the quarter ended December 31, 2020. Likewise, the results of this interim qualitative tests performed did not indicate that the Company's goodwill was impaired. First Financial will continue to monitor the status of its goodwill and intangible assets for signs of further deterioration and potential impairment.
Other intangible assets, Policy	Other intangible assets. Other intangible assets consist primarily of core deposit, customer list and other miscellaneous intangibles. CDI represent the estimated value of acquired customer deposit relationships. CDI are recorded at fair value at the date of acquisition and are based on a discounted cash flow methodology that gives appropriate consideration to expected customer attrition rates, cost of the deposit base, reserve requirements and the net maintenance cost attributable to customer deposits. Core deposit intangibles are recorded in Other intangibles on the Consolidated Balance Sheets and are amortized on an accelerated basis over their estimated useful lives. First Financial recorded a customer list intangible asset in conjunction with the Bannockburn merger to account for the obligation or advantage on the part of either the Company or the customer to continue the pre-existing relationship subsequent to the merger. The customer list intangible asset is amortized on a straight-line basis over its estimated useful life.
Loan Commitments, Policy	Loan commitments are agreements to extend credit to a client absent any violation of any condition established in the commitment agreement.  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 cash requirements.  The amount of collateral obtained, if deemed necessary by First Financial upon extension of credit, is based on management’s credit evaluation of the client.  The collateral held varies, but may include securities, real estate, inventory, plant or equipment.
Other Real Estate Owned Policy	Other real estate owned. OREO consists of properties acquired by the Company primarily through the loan foreclosure or repossession process, or other resolution activity that results in partial or total satisfaction of problem loans. OREO properties are recorded at fair value, less estimated disposal costs (net realizable value). Losses arising at the time of acquisition of such properties are charged against the ACL. Management performs periodic valuations to assess the adequacy of recorded OREO balances and subsequent changes in the carrying value of OREO properties are recorded in the Consolidated Statements of Income. Improvements to OREO properties may be capitalized if the improvements contribute to the overall value of the property, but may not be capitalized in excess of the net realizable value of the property. When management disposes of an OREO property, any gains or losses realized at the time of disposal are reflected in the Consolidated Statements of Income.
Affordable Housing Program Policy	Affordable housing projects. First Financial has investments in certain qualified affordable housing projects. These projects are indirect federal subsidies that provide tax incentives to encourage investment in the development, acquisition and rehabilitation of affordable rental housing, and allow investors to claim tax credits and other tax benefits (such as deductions from taxable income for operating losses) on their federal income tax returns. The principal risk associated with qualified affordable housing investments is the potential for noncompliance with the tax code requirements, such as failure to rent
Investments in Historic Tax Credits [Policy Text Block]	Investments in historic tax credits. First Financial has noncontrolling financial investments in private investment funds and partnerships which are not consolidated. These investments may generate a return through the realization of federal and state income tax credits, as well as other tax benefits, such as tax deductions from net operating losses of the investments over a period of time. Investments in historic tax credits are accounted for under the equity method of accounting. The Company’s recorded investment in these entities is carried in Accrued interest and other assets on the Consolidated Balance Sheets. For historic tax credits, impairment is recorded in Other noninterest expense. These tax credits and other net tax benefits received are recognized as a component of income tax expense in the Consolidated Statements of Income.
Renewable Energy Tax Credits Policy text block	Investments in renewable energy credits. First Financial has investments in renewable energy projects where it has noncontrolling interest which is not consolidated. This investment may generate a return through the realization of federal and state income tax credits, as well as other tax benefits, such as tax deductions from net operating losses of the investments over a period of time. Investments in renewable energy tax credits are accounted for under the equity method of accounting and are included in Accrued interest and other assets on the Consolidated Balance Sheets. These tax credits and other net tax benefits received are recognized as a component of income tax expense in the Consolidated Statements of Income.
Income Tax, Policy	Income taxes. First Financial and its subsidiaries file a consolidated federal income tax return. Each subsidiary provides for income taxes on a separate return basis, and remits to First Financial amounts determined to be currently payable. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Interest and penalties on income tax assessments or income tax refunds are recorded in Other noninterest expense in the Consolidated Statements of Income.
Pension and Other Postretirement Plans, Pensions, Policy	Pension. First Financial sponsors a non-contributory defined benefit pension plan covering substantially all employees. The measurement of the accrued benefit liability and the annual pension expense involves actuarial and economic assumptions, which include the discount rate, the expected return on plan assets and the rate of compensation increase.
Derivatives, Policy	Derivative instruments. First Financial accounts for its derivative financial instruments in accordance with FASB ASC Topic 815, Derivatives and Hedging. FASB ASC Topic 815 requires all derivative instruments to be carried at fair value on the balance sheet. The accounting for changes in the fair value of derivatives is based on the intended use of the derivative and the resulting designation. Derivatives used to hedge the exposure to changes in the fair value of an asset, liability or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivatives used to hedge the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Client derivatives - First Financial utilizes matched interest rate swaps as a means to offer commercial borrowers fixed rate funding while providing the Company with floating rate assets. Upon entering into an interest rate swap with a borrower, the Bank simultaneously enters into an offsetting swap agreement with an institutional counterparty, with substantially matching terms. These matched interest rate swap agreements generally involve the receipt by First Financial of floating rate amounts from the counterparties in exchange for payments to these counterparties by First Financial of fixed rate amounts received from commercial borrowers over the life of the agreements. First Financial's matched interest rate swaps qualify as derivatives, but are not designated as hedging instruments. The net interest receivable or payable on matched interest rate swaps is accrued and recognized as an adjustment to interest income. The fair values of client derivatives are included within Accrued interest and other assets and Accrued interest and other liabilities in the Consolidated Balance Sheets. First Financial may enter into foreign exchange derivative contracts for the benefit of commercial customers to hedge their exposure to foreign currency fluctuations. Similar to the hedging of interest rate risk from interest rate derivative contracts, First Financial also enters into foreign exchange contracts with major financial institutions to economically hedge a substantial portion of the exposure from client driven foreign exchange activity. These derivatives are classified as free-standing instruments with the revaluation gain or loss recorded in Foreign exchange income in the Consolidated Statements of Income. Credit derivatives - In conjunction with participating interests in commercial loans, First Financial periodically enters into risk participation agreements with counterparties whereby First Financial assumes a portion of the credit exposure associated with an interest rate swap on the participated loan in exchange for a fee. Under these agreements, First Financial will make payments to the counterparty if the loan customer defaults on its obligation to perform under the interest rate swap contract with the counterparty. The fair value of these agreements is recorded in the Consolidated Balance Sheets in Accrued interest and other liabilities. Mortgage derivatives - First Financial enters into IRLCs and forward commitments for the future delivery of mortgage loans to third party investors, which are considered derivatives. When borrowers secure an IRLC with First Financial and the loan is intended to be sold, First Financial will enter into forward commitments for the future delivery of the loans to third party investors in order to hedge against the effect of changes in interest rates impacting IRLCs and and Loans held for sale. The fair value of these agreements is recorded in the Consolidated Balance Sheets in Accrued interest and other assets.
Share-based Compensation, Option and Incentive Plans Policy	Stock-based compensation. First Financial grants stock-based awards, including restricted stock awards and options to purchase the Company’s common stock. Stock option grants are for a fixed number of shares to employees and directors with an exercise price equal to the fair value of the shares at the date of grant. Stock-based compensation expense is recognized in the Consolidated Statements of Income on a straight-line basis over the vesting period. As compensation expense is recognized, a deferred tax asset is recorded that represents an estimate of the future tax deduction from exercise. At the time stock-based awards are exercised, canceled or expire, First Financial may be required to recognize an adjustment to tax expense.
Earnings Per Share, Policy	Earnings per share. Basic earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of shares of common stock outstanding during the period. Diluted earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of common shares outstanding, unvested shares and dilutive common stock equivalents outstanding during the period. Common stock equivalents, which consist of common stock issuable under the assumed exercise of stock options granted under First Financial's stock-based compensation plans and the assumed conversion of common stock warrants, are calculated using the treasury stock method.
Segment Reporting, Policy	Segments and related information. While the Company monitors the operating results of its six lines of business, operations are managed and financial performance is evaluated on a consolidated basis. Accordingly, and consistent with prior years, all of the Company's operations are considered by management to be aggregated in one reportable operating segment.
Off-Balance-Sheet Credit Exposure, Policy	Letters of credit are conditional commitments issued by First Financial to guarantee the performance of a client to a third party.  First Financial’s portfolio of letters of credit consists primarily of performance assurances made on behalf of clients who have a contractual commitment to produce or deliver goods or services.  The risk to First Financial arises from its obligation to make payment in the event of the client's contractual default to produce the contracted good or service to a third party.
Loans and Leases Receivable, Past Due Status, Policy [Policy Text Block]	Delinquency. Loans are considered past due or delinquent when the contractual principal or interest due in accordance with the terms of the loan agreement or any portion thereof remains unpaid after the due date of the scheduled payment.
Loans and Leases Receivable, Nonaccrual Loan and Lease Status, Policy	Nonaccrual. Loans are classified as nonaccrual when, in the opinion of management, collection of principal or interest is doubtful or when principal or interest payments are 90 days or more past due. Generally, loans are classified as nonaccrual due to the continued failure to adhere to contractual payment terms by the borrower, coupled with other pertinent factors. When a loan is classified as nonaccrual, the accrual of interest income is discontinued and previously accrued but unpaid interest is reversed. Any payments received while a loan is on nonaccrual status are applied as a reduction to the carrying value of the loan. A loan classified as nonaccrual may return to accrual status if none of the principal and interest is due and unpaid, and the Bank expects repayment of the remaining contractual principal and interest.
Troubled Debt Restructuring [Policy Text Block]	Troubled debt restructurings. A loan modification is considered a TDR when the borrower is experiencing financial difficulty and concessions are made by the Company that would not otherwise be considered for a borrower with similar credit characteristics. The most common types of modifications include interest rate reductions, maturity extensions and modifications to principal amortization, including interest-only structures. Modified terms are dependent upon the financial position and needs of the individual borrower. If the modification agreement is violated, the loan is managed by the Company’s credit administration group for resolution, which may result in foreclosure in the case of real estate. In accordance with the CARES Act, performing loans that demonstrated limited signs of credit deterioration, but were modified to provide borrowers relief during the COVID-19 pandemic were not considered to be TDR as of December 31 2020.
Impaired Financing Receivable, Policy	Loans classified as nonaccrual and loans modified as TDRs are considered nonperforming for 2020 and impaired as of December 31, 2019.
Loans and Leases Receivable, Real Estate Acquired Through Foreclosure, Policy	OREO is comprised of properties acquired by the Company primarily through the loan foreclosure or repossession process, that result in partial or total satisfaction of problem loans.
Fair Value of Financial Instruments, Policy	The following methods, assumptions and valuation techniques were used by First Financial to measure different financial assets and liabilities at fair value on a recurring or nonrecurring basis. Investment securities. Investment securities classified as available-for-sale are recorded at fair value on a recurring basis. Fair value measurement is based upon quoted market prices, when available (Level 1). If quoted market prices are not available, fair values are measured utilizing independent valuation techniques of identical or similar investment securities. First Financial compiles prices from various sources who may apply such techniques as matrix pricing to determine the value of identical or similar investment securities (Level 2). Matrix pricing is a mathematical technique widely used in the banking industry to value investment securities without relying exclusively on quoted prices for the specific investment securities but rather relying on the investment securities’ relationship to other benchmark quoted investment securities. Any investment securities not valued based upon the methods previously described are considered Level 3. First Financial utilizes values provided by third-party pricing vendors to price the investment securities portfolio in accordance with the fair value hierarchy of the Fair Value Topic and reviews the pricing methodologies utilized by the pricing vendors to ensure that the fair value determination is consistent with the applicable accounting guidance. First Financial’s pricing process includes a series of quality assurance activities where prices are compared to recent market conditions, historical prices and other independent pricing services. Further, the Company periodically validates the fair value of a sample of securities in the portfolio by comparing the fair values to prices from other independent sources for the same or similar securities. First Financial analyzes unusual or significant variances, conducts additional research with the pricing vendor, and if necessary, takes appropriate action based on its findings. The results of the quality assurance process are incorporated into the selection of pricing providers by the portfolio manager. Loans held for sale. The fair value of the Company’s residential mortgage loans held for sale is determined on a recurring basis based on quoted prices for similar loans in active markets, and therefore, is classified as a Level 2 measurement. Derivatives. The fair values of derivative instruments are based primarily on a net present value calculation of the cash flows related to the interest rate swaps and foreign exchange contracts at the reporting date, using primarily observable market inputs such as interest rate yield curves and currency exchange rates, which represents the cost to terminate the swap if First Financial should choose to do so. Additionally, First Financial utilizes an internally-developed model to value the credit risk component of derivative assets and liabilities, which is recorded as an adjustment to the fair value of the derivative asset or liability on the reporting date. Derivative instruments are classified as Level 2 in the fair value hierarchy. Collateral dependent loans. Collateral dependent loans carried at fair value have been partially charged-off or receive specific allocations of the allowance for credit losses. For collateral dependent loans, fair value is generally based on real estate appraisals, a calculation of enterprise value or a valuation of business assets including equipment, inventory and accounts receivable. These loans had a principal amount of $45.3 million, with a valuation allowance of $13.5 million at December 31, 2020. The value of real estate collateral is determined utilizing an income or market valuation approach based on an appraisal conducted by an independent, licensed third-party appraiser (Level 3). These appraisals may utilize a single valuation approach or a combination of approaches including the comparable sales approach and the income approach. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between the comparable sales and income data available. Collateral is then adjusted or discounted based on management’s historical knowledge, changes in market conditions from the time of the valuation, and management’s expertise and knowledge of the client and the client’s business, resulting in a Level 3 fair value classification. Collateral dependent loans are evaluated on a quarterly basis for additional write-downs and are adjusted accordingly. Enterprise value is defined as imputed value for the entire underlying business. To determine an appropriate range of enterprise value, FFB relies on a standardized set of valuation methodologies that take into account future projected cash flows, market based multiples as well as asset values. Valuations involve both quantitative and qualitative considerations and professional judgments concerning differences in financial and operating characteristics in addition to other factors that may impact values over time (Level 3). The value of business equipment is based on an outside appraisal, if deemed significant, or the net book value on the applicable borrower financial statements. Likewise, values for inventory and accounts receivable collateral are based on borrower financial statement balances or aging reports on a discounted basis as appropriate (Level 3). The fair value of collateral dependent loans is measured at fair value on a nonrecurring basis. Any fair value adjustments are recorded in the period incurred as provision for credit losses on the Consolidated Statements of Income. OREO. Assets acquired through loan foreclosure are recorded at fair value less costs to sell, with any difference between the fair value of the property and the carrying value of the loan recorded as a charge-off. If the fair value is higher than the carrying amount of the loan, the excess is recognized first as a recovery and then as noninterest income. Subsequent declines in value are reported as adjustments to the carrying amount and are recorded in noninterest expense. The carrying value of OREO is not re-measured to fair value on a recurring basis, but is subject to fair value adjustments when the carrying value differs from the fair value, less estimated selling costs. Fair value is based on recent real estate appraisals and is updated at least annually. The Company classifies OREO in level 3 of the fair value hierarchy.
Other Contract-Mortgage
Derivatives, Methods of Accounting, Hedging Derivatives	First Financial enters into IRLCs and forward commitments for the future delivery of mortgage loans to third party investors, which are considered derivatives. When borrowers secure an IRLC with First Financial and the loans are intended to be sold, First Financial will enter into forward commitments for the future delivery of the loans to third party investors in order to hedge against the effect of changes in interest rates impacting IRLCs and and loans held for sale.
Credit Risk
Derivatives, Methods of Accounting, Hedging Derivatives	First Financial manages this market value credit risk through counterparty credit policies including a review of total derivative notional position to total assets, total credit exposure to total capital and counterparty credit exposure risk
Fair Value Hedges
Derivatives, Methods of Accounting, Hedging Derivatives	First Financial utilizes interest rate swaps as a means to offer commercial borrowers fixed rate funding while providing the Company with floating rate assets.

RECENTLY ADOPTED AND ISSUED A_2

RECENTLY ADOPTED AND ISSUED ACCOUNTING STANDARDS (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Standards Update and Change in Accounting Principle [Abstract]
Accounting Standards Update and Change in Accounting Principle	The impact of adopting ASC 326 was as follows: January 1, 2020 (dollars in thousands) As Reported under ASC 326 Pre-ASC 326 Impact of ASC 326 Adoption Assets Loans Commercial and industrial $ 28,485 $ 18,584 $ 9,901 Lease financing 1,089 971 118 Construction real estate 13,960 2,381 11,579 Commercial real estate 47,697 23,579 24,118 Residential real estate 10,789 5,299 5,490 Home equity 13,217 4,787 8,430 Installment 1,193 392 801 Credit card 2,725 1,657 1,068 Allowance for credit losses on loans $ 119,155 $ 57,650 $ 61,505 Liabilities Deferred tax liability $ 16,252 $ 33,030 $ (16,778) Allowance for credit losses on OBS credit exposures 12,740 585 12,155

INVESTMENTS (Tables)

INVESTMENTS (Tables)	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Summary of Held-To-Maturity and Available-For-Sale Investment Securities	The following is a summary of HTM and AFS investment securities as of December 31, 2020: Held-to-maturity Available-for-sale (Dollars in thousands) Amortized Unrecognized Unrecognized Fair Amortized Unrealized Unrealized Fair U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 99 $ 4 $ 0 $ 103 Securities of U.S. government agencies and corporations 0 0 0 0 60 0 0 60 Mortgage-backed securities - residential 13,990 197 0 14,187 704,482 15,938 (237) 720,183 Mortgage-backed securities - commercial 71,737 3,485 0 75,222 584,125 10,395 (3,584) 590,936 Collateralized mortgage obligations 5,799 79 0 5,878 634,418 21,148 (445) 655,121 Obligations of state and other political subdivisions 9,911 1,239 0 11,150 856,054 46,755 (291) 902,518 Asset-backed securities 0 0 0 0 478,539 4,158 (826) 481,871 Other securities 30,250 11 0 30,261 72,252 1,544 (8) 73,788 Total $ 131,687 $ 5,011 $ 0 $ 136,698 $ 3,330,029 $ 99,942 $ (5,391) $ 3,424,580 The following is a summary of HTM and AFS investment securities as of December 31, 2019: Held-to-maturity Available-for-sale (Dollars in thousands) Amortized Unrecognized Unrecognized Fair Amortized Unrealized Unrealized Fair U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 99 $ 1 $ 0 $ 100 Securities of U.S. government agencies and corporations 0 0 0 0 156 2 0 158 Mortgage-backed securities - residential 20,818 122 (174) 20,766 421,945 9,709 (99) 431,555 Mortgage-backed securities - commercial 101,267 571 (1,225) 100,613 474,174 4,988 (2,644) 476,518 Collateralized mortgage obligations 9,763 0 (108) 9,655 769,076 16,753 (385) 785,444 Obligations of state and other political subdivisions 11,014 804 (31) 11,787 652,986 23,729 (462) 676,253 Asset-backed securities 0 0 0 0 400,081 1,414 (1,064) 400,431 Other securities 0 0 0 0 79,781 1,959 (115) 81,625 Total $ 142,862 $ 1,497 $ (1,538) $ 142,821 $ 2,798,298 $ 58,555 $ (4,769) $ 2,852,084
Summary of Investment Securities by Estimated Maturity	The following table provides a summary of investment securities by contractual maturity as of December 31, 2020, except for residential and commercial mortgage-backed securities, collateralized mortgage obligations and asset-backed securities, which are shown as single totals, due to the unpredictability of the timing in principal repayments: Held-to-maturity Available-for-sale (Dollars in thousands) Amortized Fair Amortized Fair Due in one year or less $ 0 $ 0 $ 5,745 $ 5,802 Due after one year through five years 0 0 62,930 64,886 Due after five years through ten years 36,084 37,205 161,307 169,692 Due after ten years 4,077 4,206 698,483 736,089 Mortgage-backed securities - residential 13,990 14,187 704,482 720,183 Mortgage-backed securities - commercial 71,737 75,222 584,125 590,936 Collateralized mortgage obligations 5,799 5,878 634,418 655,121 Asset-backed securities 0 0 478,539 481,871 Total $ 131,687 $ 136,698 $ 3,330,029 $ 3,424,580
Age of Gross Unrealized Losses and Associated Fair Value by Investment Category	The following tables provide the fair value and gross unrealized losses on investment securities in an unrealized loss position for which an allowance for credit losses was not recorded, aggregated by investment category and the length of time the individual securities have been in a continuous loss position: December 31, 2020 Less than 12 months 12 months or more Total (Dollars in thousands) Fair Unrealized Fair Unrealized Fair Unrealized U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 Securities of U.S. government agencies and corporations 0 0 0 0 0 0 Mortgage-backed securities - residential 57,872 (237) 0 0 57,872 (237) Mortgage-backed securities - commercial 169,825 (986) 48,158 (2,598) 217,983 (3,584) Collateralized mortgage obligations 49,161 (445) 1 0 49,162 (445) Obligations of state and other political subdivisions 60,008 (291) 0 0 60,008 (291) Asset-backed securities 84,749 (435) 68,967 (391) 153,716 (826) Other securities 4,992 (8) 0 0 4,992 (8) Total $ 426,607 $ (2,402) $ 117,126 $ (2,989) $ 543,733 $ (5,391) December 31, 2019 Less than 12 months 12 months or more Total (Dollars in thousands) Fair Unrealized Fair Unrealized Fair Unrealized U.S. Treasuries $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 Securities of U.S. Government agencies and corporations 0 0 0 0 0 0 Mortgage-backed securities - residential 40,190 (209) 11,063 (64) 51,253 (273) Mortgage-backed securities - commercial 111,658 (298) 104,069 (3,571) 215,727 (3,869) Collateralized mortgage obligations 85,248 (297) 30,628 (196) 115,876 (493) Obligations of state and other political subdivisions 118,623 (457) 7,950 (36) 126,573 (493) Asset-backed securities 125,889 (553) 54,963 (511) 180,852 (1,064) Other securities 0 0 5,649 (115) 5,649 (115) Total $ 481,608 $ (1,814) $ 214,322 $ (4,493) $ 695,930 $ (6,307)

LOANS (Tables)

LOANS (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020
LOANS - Carrying Amount of Accretable Yield for Purchased Impaired and Nonimpaired Loans [Abstract]
Commercial and Consumer Credit Exposure by Risk Attribute		The following table sets forth the Company's loan portfolio at December 31, 2020 by risk attribute and origination date: (Dollars in thousands) 2020 2019 2018 2017 2016 Prior Term Total Revolving Total Commercial & industrial Pass $ 1,141,163 $ 460,210 $ 296,221 $ 208,077 $ 122,686 $ 138,307 $ 2,366,664 $ 502,286 $ 2,868,950 Special mention 24,668 10,281 18,118 6,893 6,668 6,090 72,718 10,470 83,188 Substandard 6,709 2,370 8,022 26,565 5,124 1,192 49,982 5,389 55,371 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 1,172,540 $ 472,861 $ 322,361 $ 241,535 $ 134,478 $ 145,589 $ 2,489,364 $ 518,145 $ 3,007,509 Lease financing Pass $ 22,916 $ 22,397 $ 12,942 $ 6,967 $ 4,802 $ 2,368 $ 72,392 $ 0 $ 72,392 Special mention 290 0 0 0 0 0 290 0 290 Substandard 5 0 0 180 120 0 305 0 305 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 23,211 $ 22,397 $ 12,942 $ 7,147 $ 4,922 $ 2,368 $ 72,987 $ 0 $ 72,987 Construction real estate Pass $ 96,410 $ 259,524 $ 182,625 $ 23,185 $ 24,786 $ 426 $ 586,956 $ 19,671 $ 606,627 Special mention 0 621 18,203 9,984 661 0 29,469 0 29,469 Substandard 0 0 0 0 0 0 0 0 0 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 96,410 $ 260,145 $ 200,828 $ 33,169 $ 25,447 $ 426 $ 616,425 $ 19,671 $ 636,096 Commercial real estate - investor Pass $ 515,950 $ 1,011,898 $ 427,077 $ 378,536 $ 286,587 $ 361,403 $ 2,981,451 $ 56,398 $ 3,037,849 Special mention 0 17,463 15,534 44,426 32,408 43,704 153,535 559 154,094 Substandard 6,198 2,043 22,497 7,067 68 14,724 52,597 0 52,597 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 522,148 $ 1,031,404 $ 465,108 $ 430,029 $ 319,063 $ 419,831 $ 3,187,583 $ 56,957 $ 3,244,540 Commercial real estate - owner Pass $ 185,692 $ 162,480 $ 147,236 $ 125,275 $ 128,755 $ 211,519 $ 960,957 $ 36,721 $ 997,678 Special mention 4,292 11,380 2,891 8,230 3,017 19,384 49,194 59 49,253 Substandard 668 504 7,054 5,496 306 2,321 16,349 38 16,387 Doubtful 0 0 0 0 0 0 0 0 0 Total $ 190,652 $ 174,364 $ 157,181 $ 139,001 $ 132,078 $ 233,224 $ 1,026,500 $ 36,818 $ 1,063,318 Residential real estate Performing $ 290,277 $ 241,601 $ 115,747 $ 64,220 $ 60,094 $ 224,281 $ 996,220 $ 0 $ 996,220 Nonperforming 321 429 673 643 87 4,713 6,866 0 6,866 Total $ 290,598 $ 242,030 $ 116,420 $ 64,863 $ 60,181 $ 228,994 $ 1,003,086 $ 0 $ 1,003,086 Home equity Performing $ 60,967 $ 20,200 $ 17,445 $ 11,308 $ 9,744 $ 41,571 $ 161,235 $ 577,609 $ 738,844 Nonperforming 0 0 0 39 28 138 205 4,050 4,255 Total $ 60,967 $ 20,200 $ 17,445 $ 11,347 $ 9,772 $ 41,709 $ 161,440 $ 581,659 $ 743,099 Installment Performing $ 21,584 $ 15,614 $ 11,041 $ 8,812 $ 1,954 $ 3,185 $ 62,190 $ 19,479 $ 81,669 Nonperforming 15 53 23 35 17 36 179 2 181 Total $ 21,599 $ 15,667 $ 11,064 $ 8,847 $ 1,971 $ 3,221 $ 62,369 $ 19,481 $ 81,850 Credit cards Performing $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 47,845 $ 47,845 Nonperforming 0 0 0 0 0 0 0 640 640 Total $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 0 $ 48,485 $ 48,485 Grand Total $ 2,378,125 $ 2,239,068 $ 1,303,349 $ 935,938 $ 687,912 $ 1,075,362 $ 8,619,754 $ 1,281,216 $ 9,900,970 Commercial and consumer credit exposure by risk attribute as of December 31, 2019 was as follows: As of December 31, 2019 Real Estate (Dollars in thousands) Commercial & industrial Construction Commercial Lease Total Pass $ 2,324,021 $ 493,182 $ 4,108,752 $ 85,262 $ 7,011,217 Special Mention 100,954 0 59,383 488 160,825 Substandard 40,902 0 26,516 2,614 70,032 Doubtful 0 0 0 0 0 Total $ 2,465,877 $ 493,182 $ 4,194,651 $ 88,364 $ 7,242,074 Residential Home equity Installment Credit card Total Performing $ 1,040,787 $ 766,169 $ 82,385 $ 48,983 $ 1,938,324 Nonperforming 15,162 5,700 204 201 21,267 Total $ 1,055,949 $ 771,869 $ 82,589 $ 49,184 $ 1,959,591
Loan Delinquency, including Nonaccrual Loans		Loan delinquency, including nonaccrual loans, was as follows: As of December 31, 2020 (Dollars in thousands) 30 – 59 60 – 89 > 90 days Total Current Total > 90 days Loans Commercial & industrial $ 6,532 $ 0 $ 1,861 $ 8,393 $ 2,999,116 $ 3,007,509 $ 0 Lease financing 0 0 0 0 72,987 72,987 0 Construction real estate 0 0 0 0 636,096 636,096 0 Commercial real estate-investor 136 0 24,422 24,558 3,219,982 3,244,540 0 Commercial real estate-owner 6,480 174 400 7,054 1,056,264 1,063,318 0 Residential real estate 2,809 370 3,687 6,866 996,220 1,003,086 0 Home equity 1,483 835 1,937 4,255 738,844 743,099 0 Installment 94 35 51 180 81,670 81,850 0 Credit card 303 163 174 640 47,845 48,485 169 Total $ 17,837 $ 1,577 $ 32,532 $ 51,946 $ 9,849,024 $ 9,900,970 $ 169 As of December 31, 2019 (Dollars in thousands) 30 - 59 60 - 89 > 90 days Total Current Subtotal Purchased impaired Total > 90 days Loans Commercial & industrial $ 1,266 $ 3,332 $ 14,518 $ 19,116 $ 2,443,680 $ 2,462,796 $ 3,081 $ 2,465,877 $ 0 Lease financing 0 0 0 0 88,364 88,364 0 88,364 0 Construction real estate 0 0 0 0 493,167 493,167 15 493,182 0 Commercial real estate 776 857 5,613 7,246 4,151,513 4,158,759 35,892 4,194,651 0 Residential real estate 8,032 1,928 5,031 14,991 1,014,138 1,029,129 26,820 1,055,949 0 Home equity 2,530 1,083 2,795 6,408 762,863 769,271 2,598 771,869 0 Installment 111 50 148 309 82,022 82,331 258 82,589 0 Credit card 208 75 201 484 48,700 49,184 0 49,184 201 Total $ 12,923 $ 7,325 $ 28,306 $ 48,554 $ 9,084,447 $ 9,133,001 $ 68,664 $ 9,201,665 $ 201
Loans Restructured During Period		The following table provides information on loan modifications classified as TDRs during the years ended December 31, 2020, 2019 and 2018: Years ended December 31, 2020 2019 2018 (Dollars in thousands) Number of loans Pre-modification loan balance Period end balance Number of loans Pre-modification loan balance Period end balance Number of loans Pre-modification loan balance Period end balance Commercial & industrial 8 $ 14,984 $ 14,984 8 $ 25,009 $ 25,071 17 $ 23,943 $ 23,890 Construction 0 0 0 0 0 0 0 0 0 Commercial 0 0 0 9 3,024 2,932 8 3,385 3,150 Residential 24 1,953 1,847 30 3,415 3,062 13 1,148 1,073 Home equity 11 351 349 14 395 366 5 95 192 Installment 2 35 22 2 41 39 0 0 0 Total 45 $ 17,323 $ 17,202 63 $ 31,884 $ 31,470 43 $ 28,571 $ 28,305
Loans Restructured, Modifications		The following table provides information on how TDRs were modified during the years ended December 31, 2020, 2019 and 2018: Years Ended December 31, (Dollars in thousands) 2020 2019 2018 Extended maturities $ 0 $ 2,877 $ 4,093 Adjusted interest rates 0 5,284 52 Combination of rate and maturity changes 0 516 0 Forbearance 4,759 20,320 23,175 Other (1) 12,443 2,473 985 Total $ 17,202 $ 31,470 $ 28,305 (1) Other includes covenant modifications and other concessions or combination of concessions that do not consist of interest rate adjustments, forbearance and maturity extensions.
Loan Restructuring, Loans with a Payment Default Within 12 Months of Loan Modification
Nonaccrual, Restructured and Impaired Loans		The following table provides information on nonperforming loans as of December 31: 2020 2019 2018 (Dollars in thousands) Nonaccrual loans with a related ACL Nonaccrual loans with no related ACL Total nonaccrual Total nonaccrual Total nonaccrual Nonaccrual loans (1) Commercial & industrial $ 18,711 $ 10,519 $ 29,230 $ 24,346 $ 30,925 Lease financing 0 0 0 223 22 Construction real estate 0 0 0 0 9 Commercial real estate 6,957 27,725 34,682 7,295 20,500 Residential real estate 251 11,350 11,601 10,892 13,495 Home equity 0 5,076 5,076 5,242 5,580 Installment 0 163 163 167 169 Total nonaccrual loans $ 25,919 $ 54,833 $ 80,752 $ 48,165 $ 70,700 Interest income effect Gross amount of interest that would have been recorded under original terms $ 5,892 $ 5,813 $ 4,656 Interest included in income Nonaccrual loans 1,636 1,042 715 Troubled debt restructurings 426 801 642 Total interest included in income 2,062 1,843 1,357 Net impact on interest income $ 3,830 $ 3,970 $ 3,299 Commitments outstanding to borrowers with nonaccrual loans $ 0 $ 3 $ 200 (1) Nonaccrual loans include nonaccrual TDRs of $14.7 million, $18.5 million and $22.4 million as of December 31, 2020, 2019 and 2018, respectively.
Investment in Impaired Loans		First Financial's investment in impaired loans was as follows: December 31, 2019 (Dollars in thousands) Current balance Contractual Related Loans with no related allowance recorded Commercial & industrial $ 16,726 $ 19,709 $ 0 Lease financing 223 223 0 Construction real estate 0 0 0 Commercial real estate 10,160 17,897 0 Residential real estate 14,868 17,368 0 Home equity 5,700 6,462 0 Installment 204 341 0 Total 47,881 62,000 0 Loans with an allowance recorded Commercial & industrial 10,754 21,513 2,044 Lease financing 0 0 0 Construction real estate 0 0 0 Commercial real estate 671 675 113 Residential real estate 294 294 18 Home equity 0 0 0 Installment 0 0 0 Total 11,719 22,482 2,175 Total Commercial & industrial 27,480 41,222 2,044 Lease financing 223 223 0 Construction real estate 0 0 0 Commercial real estate 10,831 18,572 113 Residential real estate 15,162 17,662 18 Home equity 5,700 6,462 0 Installment 204 341 0 Total $ 59,600 $ 84,482 $ 2,175 Years ended December 31, 2019 2018 (Dollars in thousands) Average Interest Average Interest Loans with no related allowance recorded Commercial & industrial $ 31,846 $ 926 $ 14,498 $ 360 Lease financing 168 0 21 0 Construction real estate 6 0 20 2 Commercial real estate 18,757 357 24,738 490 Residential real estate 15,915 307 11,359 301 Home equity 5,893 121 5,541 114 Installment 170 2 274 2 Total 72,755 1,713 56,451 1,269 Loans with an allowance recorded Commercial & industrial 4,721 87 900 44 Lease financing 57 0 0 0 Construction real estate 0 0 0 0 Commercial real estate 1,339 31 1,402 18 Residential real estate 446 12 895 23 Home equity 0 0 80 3 Installment 0 0 0 0 Total 6,563 130 3,277 88 Total Commercial & industrial 36,567 1,013 15,398 404 Lease financing 225 0 21 0 Construction real estate 6 0 20 2 Commercial real estate 20,096 388 26,140 508 Residential real estate 16,361 319 12,254 324 Home equity 5,893 121 5,621 117 Installment 170 2 274 2 Total $ 79,318 $ 1,843 $ 59,728 $ 1,357
Schedule of Collateral Dependent Loans		The following table presents the amortized cost basis of collateral dependent loans by class of loan. December 31, 2020 Type of Collateral (Dollar in thousands) Business assets Commercial real estate Equipment Land Residential real estate Other Total Class of loan Commercial & industrial $ 30,961 $ 6,130 $ 2,608 $ 865 $ 0 $ 4,892 $ 45,456 Commercial real estate-investor 0 20,212 661 5,537 872 0 27,282 Commercial real estate-owner 5,842 3,495 0 42 344 0 9,723 Residential real estate 0 0 0 0 11,601 0 11,601 Home equity 0 0 0 0 5,076 0 5,076 Installment 0 0 0 0 0 163 163 Total $ 36,803 $ 29,837 $ 3,269 $ 6,444 $ 17,893 $ 5,055 $ 99,301
Changes in Other Real Estate Owned		Changes in OREO were as follows: Years ended December 31, (Dollars in thousands) 2020 2019 2018 Balance at beginning of year $ 2,033 $ 1,401 $ 2,781 Additions Commercial 510 415 1,269 Residential 507 2,033 1,913 Total additions 1,017 2,448 3,182 Disposals Commercial (217) (541) (2,967) Residential (1,859) (912) (830) Total disposals (2,076) (1,453) (3,797) Valuation adjustments Commercial 448 (112) (355) Residential (135) (251) (410) Total valuation adjustments 313 (363) (765) Balance at end of year $ 1,287 $ 2,033 $ 1,401

ALLOWANCE FOR CREDIT LOSSES (Ta

ALLOWANCE FOR CREDIT LOSSES (Tables)	12 Months Ended
	Dec. 31, 2020
Receivables [Abstract]
Changes in the Allowance for Loan and Lease Losses for the Previous Three Years	Changes in the allowance by loan category as of December 31 were as follows: 2020 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Allowance for credit losses Beginning balance, prior to adoption of ASC 326 $ 18,584 $ 971 $ 2,381 $ 23,579 $ 5,299 $ 4,787 $ 392 $ 1,657 $ 57,650 Impact of adopting ASC 326 9,901 118 11,579 24,118 5,490 8,430 801 1,068 61,505 Provision for credit losses 25,407 758 7,759 38,936 (2,122) (939) 12 985 70,796 Gross charge-offs (5,345) (852) 0 (12,100) (488) (1,541) (148) (885) (21,359) Recoveries 2,907 0 17 2,262 381 1,132 158 230 7,087 Total net charge-offs (2,438) (852) 17 (9,838) (107) (409) 10 (655) (14,272) Ending allowance for credit losses $ 51,454 $ 995 $ 21,736 $ 76,795 $ 8,560 $ 11,869 $ 1,215 $ 3,055 $ 175,679 2019 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Allowance for credit losses Balance at beginning of year $ 18,746 $ 1,130 $ 3,413 $ 21,048 $ 4,964 $ 5,348 $ 362 $ 1,531 $ 56,542 Provision for credit losses 23,631 3 (1,100) 5,107 739 695 2 1,521 30,598 Gross charge-offs (26,676) (162) 0 (3,689) (677) (2,591) (223) (1,547) (35,565) Recoveries 2,883 0 68 1,113 273 1,335 251 152 6,075 Total net charge-offs (23,793) (162) 68 (2,576) (404) (1,256) 28 (1,395) (29,490) Ending allowance for credit losses $ 18,584 $ 971 $ 2,381 $ 23,579 $ 5,299 $ 4,787 $ 392 $ 1,657 $ 57,650 2018 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Allowance for credit losses Balance at beginning of year $ 17,598 $ 675 $ 3,577 $ 20,930 $ 4,683 $ 4,935 $ 307 $ 1,316 $ 54,021 Provision for credit losses 10,615 454 (310) 847 492 829 (85) 1,744 14,586 Gross charge-offs (11,533) 0 0 (4,835) (422) (1,725) (435) (1,720) (20,670) Recoveries 2,066 1 146 4,106 211 1,309 575 191 8,605 Total net charge-offs (9,467) 1 146 (729) (211) (416) 140 (1,529) (12,065) Ending allowance for credit losses $ 18,746 $ 1,130 $ 3,413 $ 21,048 $ 4,964 $ 5,348 $ 362 $ 1,531 $ 56,542 As of December 31, 2019 (Dollars in thousands) Commercial & industrial Lease financing Construction real estate Commercial real estate Residential real estate Home equity Installment Credit card Total Ending allowance balance attributable to loans Individually evaluated for impairment $ 2,044 $ 0 $ 0 $ 113 $ 18 $ 0 $ 0 $ 0 $ 2,175 Collectively evaluated for impairment 16,540 971 2,381 23,466 5,281 4,787 392 1,657 55,475 Ending allowance for credit losses $ 18,584 $ 971 $ 2,381 $ 23,579 $ 5,299 $ 4,787 $ 392 $ 1,657 $ 57,650 Loans Individually evaluated for impairment $ 27,480 $ 223 $ 0 $ 10,831 $ 15,162 $ 5,700 $ 204 $ 0 $ 59,600 Collectively evaluated for impairment 2,438,397 88,141 493,182 4,183,820 1,040,787 766,169 82,385 49,184 9,142,065 Total loans $ 2,465,877 $ 88,364 $ 493,182 $ 4,194,651 $ 1,055,949 $ 771,869 $ 82,589 $ 49,184 $ 9,201,665

PREMISES AND EQUIPMENT (Tables)

PREMISES AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment [Table Text Block]	Premises and equipment at December 31 were as follows: (Dollars in thousands) 2020 2019 Land and land improvements $ 52,373 $ 54,958 Buildings 161,371 163,277 Furniture and fixtures 70,177 74,881 Leasehold improvements 29,525 31,728 Construction in progress 8,434 4,096 321,880 328,940 Less: Accumulated depreciation and amortization 114,669 114,434 Total $ 207,211 $ 214,506

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lease, Cost [Table Text Block]	The components of lease expense for the years ended December 31, 2020 and 2019 were as follows: (dollars in thousands) December 31, 2020 December 31, 2019 Operating lease cost $ 7,897 $ 7,324 Short-term lease cost 142 55 Variable lease cost 2,532 2,553 Total operating lease cost $ 10,571 $ 9,932
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	Future minimum commitments due under these lease agreements as of December 31, 2020 are as follows: (dollars in thousands) Operating leases 2021 $ 6,864 2022 7,074 2023 7,143 2024 6,858 2025 6,217 Thereafter 56,951 Total lease payments 91,107 Less imputed interest 19,395 Total $ 71,712
Schedule of supplemental balance sheet information related to leases. [Table Text Block]	The weighted average lease term and discount rate for the Company's operating leases were as follows: December 31, 2020 December 31, 2019 Operating leases Weighted-average remaining lease term 15.1 years 15.6 years Weighted-average discount rate 3.07 % 3.43 %
Schedule of supplemental cash flow information related to leases [Table Text Block]	Supplemental cash information at year end related to leases was as follows: (dollars in thousands) December 31, 2020 December 31, 2019 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from operating leases $ 8,196 $ 7,335 ROU assets obtained in exchange for lease obligations Operating leases 9,725 64,902

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill	Changes in the carrying amount of goodwill for the years ended December 31, 2020, 2019 and 2018 are shown below. (Dollars in thousands) 2020 2019 2018 Balance at beginning of year $ 937,771 $ 880,251 $ 204,084 Goodwill resulting from business combinations 0 57,520 676,167 Balance at end of year $ 937,771 $ 937,771 $ 880,251
Schedule of Finite-Lived Intangible Assets	The gross carrying amount and accumulated amortization of other intangible assets at December 31, 2020 and December 31, 2019 were as follows: (Dollars in thousands) December 31, 2020 December 31, 2019 Amortized intangible assets Core deposit intangibles $ 51,031 $ (27,524) $ 51,031 $ (21,149) Customer list 39,420 (4,778) 39,420 (1,195) Other 10,113 (3,710) 10,093 (1,999) Total $ 100,564 $ (36,012) $ 100,544 $ (24,343)
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The estimated amortization expense of intangible assets for the next five years is as follows: (Dollars in thousands) Intangible amortization 2021 $ 10,249 2022 7,708 2023 6,729 2024 6,660 2025 6,611

DEPOSITS (Tables)

DEPOSITS (Tables)	12 Months Ended
	Dec. 31, 2020
Deposits [Abstract]
Maturities of time deposits [Table Text Block]	Scheduled maturities of all time deposits for the next five years were as follows: (Dollars in thousands) Time deposits 2021 $ 1,544,131 2022 215,855 2023 56,882 2024 32,978 2025 22,210 Thereafter 677 Total $ 1,872,733

BORROWINGS (Tables)

BORROWINGS (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule Of Remaining Contractual Maturity Of Secured Borrowings And Class Of Collateral Pledged Under Repurchase Agreements Table [Table Text Block]	The following shows the remaining contractual maturity of repurchase agreements by collateral pledged: (Dollars in thousands) Overnight and Continuous Repurchase agreements Mortgage-backed securities $ 79,235 Collateralized mortgage obligations 47,359 Total $ 126,594
Schedule of Short-term Debt [Table Text Block]	The following is a summary of short-term borrowings for the last three years: 2020 2019 2018 (Dollars in thousands) Amount Rate Amount Rate Amount Rate At December 31, Federal funds purchased and securities sold under agreements to repurchase $ 166,594 0.05 % $ 165,181 0.85 % $ 183,591 1.65 % FHLB borrowings 0 0.00 % 1,151,000 1.73 % 857,100 2.48 % Total $ 166,594 0.05 % $ 1,316,181 1.62 % $ 1,040,691 2.33 % Average for the year Federal funds purchased and securities sold under agreements to repurchase $ 149,036 0.26 % $ 155,859 1.15 % $ 87,221 0.58 % FHLB borrowings 441,867 1.37 % 990,860 2.37 % 857,028 2.03 % Other short-term borrowings 0 0.00 % 0 0.00 % 3,178 4.36 % Total $ 590,903 1.09 % $ 1,146,719 1.90 % $ 947,427 1.90 % Maximum month-end balances Federal funds purchased and securities sold under agreements to repurchase $ 260,621 $ 260,621 $ 183,591 FHLB borrowings 1,171,400 1,171,400 1,170,800 Other short-term borrowings 0 0 10,000
Summary of Long-term Debt [Table Text Block]	The following is a summary of First Financial's long-term debt: 2020 2019 (Dollars in thousands) Amount Average Rate Amount Average Rate FRB borrowings $ 434,982 0.35 % $ 0 n/a FHLB borrowings 19,971 1.43 % 242,428 1.94 % Subordinated debt 321,384 4.86 % 170,967 4.97 % Unamortized debt issuance costs (2,770) n/a (1,007) n/a Capital lease liability 1,860 3.81 % 1,213 4.48 % Capital loan with municipality 775 0.00 % 775 0.00 % Total long-term debt $ 776,202 2.25 % $ 414,376 3.20 %
Schedule of Maturities of Long-term Debt [Table Text Block]	As of December 31, 2020, First Financial's long-term debt matures as follows: (Dollars in thousands) Long-term debt 2021 $ 20,050 2022 435,065 2023 87 2024 91 2025 96 Thereafter 320,813 Total $ 776,202

DERIVATIVES (Tables)

DERIVATIVES (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Derivative Financial Instruments and Balances	The following table details the location and amounts of client derivatives and foreign exchange contracts recognized in the Consolidated Balance Sheets: December 31, 2020 December 31, 2019 Estimated fair value Estimated fair value (Dollars in thousands) Balance Notional Gain Loss Notional Gain Loss Client derivatives-instruments associated with loans Matched interest rate swaps with borrower Accrued interest and other assets and other liabilities $ 2,300,336 $ 184,777 $ (107) $ 1,923,375 $ 70,799 $ (2,636) Matched interest rate swaps with counterparty Accrued interest and other liabilities 2,300,336 107 (184,884) 1,923,375 2,636 (70,808) Foreign exchange contracts Matched foreign exchange contracts with customers Accrued interest and other assets 3,637,509 60,366 (27,249) 1,869,934 28,739 (10,433) Match foreign exchange contracts with counterparty Accrued interest and other liabilities 3,637,509 27,249 (60,366) 1,869,934 10,433 (28,739) Total $ 11,875,690 $ 272,499 $ (272,606) $ 7,586,618 $ 112,607 $ (112,616)
Disclosure by Type of Financial Instrument [Table Text Block]	The following table discloses the gross and net amounts of client derivatives and foreign exchange contracts recognized in the Consolidated Balance Sheets: December 31, 2020 December 31, 2019 (Dollars in thousands) Gross amounts of recognized liabilities Gross amounts offset in the Consolidated Balance Sheets Net amounts of (assets)/liabilities presented in the Consolidated Balance Sheets Gross amounts of recognized liabilities Gross amounts offset in the Consolidated Balance Sheets Net amounts of (assets)/liabilities presented in the Consolidated Balance Sheets Client derivatives Matched interest rate swaps $ 184,991 $ (385,088) $ (200,097) $ 73,444 $ (147,193) $ (73,749) Foreign exchange contracts with counterparty 87,615 (17,392) 70,223 39,172 (41,202) (2,030) Total $ 272,606 $ (402,480) $ (129,874) $ 112,616 $ (188,395) $ (75,779)
Derivative Financial Instruments, Average Remaining Maturity and the Weighted-Average Interest Rates being Paid and Received	The following table details the derivative financial instruments, the average remaining maturities and the weighted-average interest rates being paid and received by First Financial at December 31, 2020: (Dollars in thousands) Notional Average Fair Client derivatives-interest rate contracts Receive fixed, matched interest rate swaps with borrower $ 2,300,336 4.9 $ 184,670 Pay fixed, matched interest rate swaps with counterparty 2,300,336 4.9 (184,777) Client derivatives-foreign exchange contracts Foreign exchange contracts - pay USD 3,637,509 0.6 33,117 Foreign exchange contracts - receive USD 3,637,509 0.6 (33,117) Total client derivatives $ 11,875,690 2.3 $ (107)

RELATED PARTIES TRANSACTIONS (T

RELATED PARTIES TRANSACTIONS (Tables)	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Schedule of Loans to Related Parties [Table Text Block]	Outstanding balance of loans to directors, executive officers, principal holders of First Financial’s common stock and certain related persons were as follows: (Dollars in thousands) 2020 Beginning balance $ 5,289 Additions 1,811 Deductions (2,003) Ending balance $ 5,097 Loans 90 days or more past due $ 0

COMMITMENTS AND CONTINGENCIES C

COMMITMENTS AND CONTINGENCIES COMMITMENTS AND CONTINGENCIES (Tables)	6 Months Ended
	Jun. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies [Table Text Block]	The following table presents First Financial's loan balances and contractual obligations to extend credit as of December 31, 2020. (dollars in thousands) Unfunded commitment Loan balance Commercial & industrial $ 1,270,765 $ 3,007,509 Lease financing 0 72,987 Construction real estate 374,008 636,096 Commercial real estate-investor 139,754 3,244,540 Commercial real estate-owner 51,637 1,063,318 Residential real estate 28,895 1,003,086 Home equity 762,406 743,099 Installment 18,229 81,850 Credit card 207,365 48,485 Total $ 2,853,059 $ 9,900,970

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	Income tax expense consisted of the following components: (Dollars in thousands) 2020 2019 2018 Current expense Federal $ 34,632 $ 31,343 $ 34,330 State 2,349 854 1,029 Total current expense 36,981 32,197 35,359 Deferred expense (benefit) Federal (8,624) 10,946 4,675 State 244 1,644 1,592 Total deferred expense (benefit) (8,380) 12,590 6,267 Income tax expense $ 28,601 $ 44,787 $ 41,626
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The difference between the federal income tax rates applied to income before income taxes and the effective rates were due to the following: (Dollars in thousands) 2020 2019 2018 Income taxes computed at federal statutory rate (21%) on income before income taxes $ 38,726 $ 51,001 $ 44,986 Benefit from tax-exempt income (5,901) (5,964) (4,499) Tax credits (13,064) (10,075) (5,439) Basis reduction on tax credit 657 738 0 Tax expense (benefit) of equity compensation 340 (140) (565) State income taxes, net of federal tax benefit 2,049 1,973 2,070 Affordable housing investments 6,635 5,825 4,725 Other (841) 1,429 348 Income tax expense $ 28,601 $ 44,787 $ 41,626
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	The major components of the temporary differences that gave rise to deferred tax assets and liabilities at December 31, 2020, and 2019, were as follows: (Dollars in thousands) 2020 2019 Deferred tax assets Allowance for credit losses $ 39,671 $ 13,011 Fair value adjustments on business combinations 3,870 6,470 Deferred compensation 235 228 Postretirement benefits other than pension liability 684 666 Accrued stock-based compensation 1,654 1,296 OREO write-downs 8 162 Interest on nonaccrual loans 1,712 548 Accrued expenses 5,647 4,708 State net operating loss 1,959 2,792 Leasing liability 16,947 14,806 Reserve for unfunded commitments 2,854 133 Deferred loan fees and costs 1,691 0 Other 577 683 Total deferred tax assets 77,509 45,503 Deferred tax liabilities Tax depreciation in excess of book depreciation (11,923) (10,970) FHLB and FRB stock (4,043) (4,043) Mortgage-servicing rights (2,925) (2,435) Leasing activities (6,661) (7,349) Retirement obligation (10,984) (8,511) Intangible assets (13,942) (11,647) Deferred loan fees and costs 0 (1,100) Prepaid expenses (619) (623) Limited partnership investments (2,471) (2,249) Net unrealized gains on investment securities (20,253) (11,359) Foreign exchange deferred income (2,080) (2,845) ASU 2016-01 unrealized gain/loss-equity securities (2,179) (128) Right of use assets (15,053) (13,354) Other (2,035) (1,920) Total deferred tax liabilities (95,168) (78,533) Total net deferred tax liability $ (17,659) $ (33,030)
Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table Text Block]	A progression of gross unrecognized tax benefits as of December 31, 2020 and 2019 is as follows: (Dollars in thousands) 2020 2019 Balance at beginning of year $ 3,006 $ 3,735 Settlements (620) (729) Balance at end of year $ 2,386 $ 3,006

EMPLOYEE BENEFIT PLANS (Tables)

EMPLOYEE BENEFIT PLANS (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020
Retirement Benefits [Abstract]
Schedule of Amounts Recognized in Balance Sheet and Income Statement [Table Text Block]		The following tables set forth information concerning amounts recognized in First Financial's Consolidated Balance Sheets and Consolidated Statements of Income related to the Company's pension plan: December 31, (Dollars in thousands) 2020 2019 Change in benefit obligation Benefit obligation at beginning of year $ 75,044 $ 68,286 Service cost 7,932 6,591 Interest cost 2,455 2,778 Actuarial (gain) loss 9,171 6,848 Benefits paid, excluding settlement (7,108) (9,459) Benefit obligation at end of year 87,494 75,044 Change in plan assets Fair value of plan assets at beginning of year 141,816 130,078 Actual return on plan assets 20,996 21,197 Benefits paid, excluding settlement (7,108) (9,459) Fair value of plan assets at end of year 155,704 141,816 Amounts recognized in the Consolidated Balance Sheets Assets 68,210 66,772 Liabilities 0 0 Net amount recognized $ 68,210 $ 66,772 Amounts recognized in accumulated other comprehensive income (loss) Net actuarial loss $ 32,943 $ 37,278 Net prior service cost (682) (1,095) Deferred tax assets (7,349) (8,242) Net amount recognized $ 24,912 $ 27,941 Change in accumulated other comprehensive income (loss) $ (3,029) $ (4,649) Accumulated benefit obligation $ 86,327 $ 74,424
Schedule of Components of Net Periodic Benefit Cost [Table Text Block]		The components of net periodic benefit cost are shown in the table that follows: December 31, (Dollars in thousands) 2020 2019 2018 Service cost $ 7,932 $ 6,591 $ 6,501 Interest cost 2,455 2,778 2,394 Expected return on assets (9,824) (9,718) (9,811) Amortization of prior service cost (413) (413) (413) Recognized net actuarial loss 2,334 1,803 2,188 Net periodic benefit (income) cost 2,484 1,041 859 Other changes recognized in accumulated other comprehensive income (loss) Net actuarial (gain) loss (2,001) (4,630) 12,319 Prior service cost 0 0 0 Amortization of prior service cost 413 413 413 Amortization of gain (2,334) (1,803) (2,188) Total recognized in accumulated other comprehensive income (loss) (3,922) (6,020) 10,544 Total recognized in net periodic benefit cost and accumulated other comprehensive income (loss) $ (1,438) $ (4,979) $ 11,403
Defined Benefit Plan, Assumptions [Table Text Block]		The pension plan assumptions are shown in the table that follows: December 31, 2020 2019 2018 Benefit obligations Discount rate 2.55 % 3.33 % 4.31 % Rate of compensation increase 3.50 % 3.50 % 3.50 % Weighted average interest crediting rate 2.14 % 2.82 % 3.61 % Net periodic benefit cost Discount rate 3.33 % 4.31 % 3.43 % Expected return on plan assets 7.25 % 7.25 % 7.25 % Rate of compensation increase 3.50 % 3.50 % 3.50 % Weighted average interest crediting rate 2.82 % 3.61 % 2.63 %
Schedule of Changes in Fair Value of Plan Assets [Table Text Block]		The fair value of the plan assets as of December 31, 2020 by asset category is shown in the table that follows: Fair Value Measurements (Dollars in thousands) Total Quoted Prices in Significant Significant Asset Category Cash $ 129 $ 129 $ 0 $ 0 U. S. Government agencies 4,193 0 4,193 0 Fixed income mutual funds 65,443 65,443 0 0 Equity mutual funds 85,939 85,939 0 0 Total $ 155,704 $ 151,511 $ 4,193 $ 0 The fair value of the plan assets as of December 31, 2019 by asset category is shown in the table that follows: Fair Value Measurements (Dollars in thousands) Total Quoted Prices in Significant Significant Asset Category Cash $ 195 $ 195 $ 0 $ 0 U. S. Government agencies 5,357 0 5,357 0 Fixed income mutual funds 75,720 75,720 0 0 Equity mutual funds 60,544 60,544 0 0 Total $ 141,816 $ 136,459 $ 5,357 $ 0
Schedule of Expected Benefit Payments [Table Text Block]	The following benefit payments, which reflect expected future service, are expected to be paid: (Dollars in thousands) Expected benefit payments 2021 $ 5,780 2022 5,432 2023 5,474 2024 6,605 2025 6,565 Thereafter 38,095

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	6 Months Ended
	Jun. 30, 2020
Equity [Abstract]
Related Tax Effects Allocated to Other Comprehensive Income and Accumulated Other Comprehensive Income (Loss)	The related tax effects allocated to other comprehensive income and accumulated other comprehensive income (loss) are as follows: December 31, 2020 Total other comprehensive income (loss) Total accumulated (Dollars in thousands) Prior to Reclass Pre-tax Tax effect Net of tax Beginning balance Net activity Ending balance Unrealized gain (loss) on debt securities $ 36,643 $ (4,563) $ 41,206 $ (8,894) $ 32,312 $ 41,264 $ 32,312 $ 73,576 Unrealized gain (loss) on derivatives 0 0 0 0 0 0 0 0 Retirement obligation 2,001 (1,921) 3,922 (893) 3,029 (27,941) 3,029 (24,912) Total $ 38,644 $ (6,484) $ 45,128 $ (9,787) $ 35,341 $ 13,323 $ 35,341 $ 48,664 December 31, 2019 Total other comprehensive income (loss) Total accumulated other (Dollars in thousands) Prior to Reclass Pre-tax Tax-effect Net of tax Beginning Balance Net Activity Cumulative effect of new standard Ending Balance Unrealized gain (loss) on debt securities $ 65,858 $ (370) $ 66,228 $ (14,269) $ 51,959 $ (11,601) $ 51,959 $ 906 $ 41,264 Unrealized gain (loss) on derivatives 281 0 281 (64) 217 (217) 217 0 0 Retirement obligation 4,630 (1,390) 6,020 (1,371) 4,649 (32,590) 4,649 0 (27,941) Total $ 70,769 $ (1,760) $ 72,529 $ (15,704) $ 56,825 $ (44,408) $ 56,825 $ 906 $ 13,323 December 31, 2018 Total other comprehensive income (loss) Total accumulated other (Dollars in thousands) Prior to Reclass Pre-tax Tax-effect Net of tax Beginning Balance Net Activity Cumulative effect of new standard Ending Balance Unrealized gain (loss) on debt securities $ (14,461) $ (161) $ (14,300) $ 3,071 $ (11,229) $ (182) $ (11,229) $ (190) $ (11,601) Unrealized gain (loss) on derivatives 628 0 628 (144) 484 (577) 484 (124) (217) Retirement obligation (12,319) (1,775) (10,544) 2,364 (8,180) (19,631) (8,180) (4,779) (32,590) Total $ (26,152) $ (1,936) $ (24,216) $ 5,291 $ (18,925) $ (20,390) $ (18,925) $ (5,093) $ (44,408)
Other Accumulated Comprehensive income reclassified from AOCI [Table Text Block]	The following table details the activity reclassified from accumulated other comprehensive income into income during the period: Amount Reclassified from Accumulated Other Comprehensive Income (1) December 31, (Dollars in thousands) 2020 2019 2018 Affected Line Item in the Consolidated Statements of Income Realized gains and losses on securities available-for-sale $ (4,563) $ (370) $ (161) Net gain (loss) on sales of investment securities Defined benefit pension plan Amortization of prior service cost (2) 413 413 413 Other noninterest expense Recognized net actuarial loss (2) (2,334) (1,803) (2,188) Other noninterest expense Amortization and settlement charges of defined benefit pension items (1,921) (1,390) (1,775) Total reclassifications for the period, before tax $ (6,484) $ (1,760) $ (1,936) (1) Negative amounts are debits to profit/loss. (2) Included in the computation of net periodic pension cost (see Note 16 - Employee Benefit Plans for additional details).

CAPITAL (Tables)

CAPITAL (Tables)	6 Months Ended
	Jun. 30, 2020
Banking Regulation, Total Capital [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block]	Actual Minimum capital PCA requirement to be (Dollars in thousands) Capital Ratio Capital Ratio Capital Ratio December 31, 2020 Common equity tier 1 capital to risk-weighted assets Consolidated $ 1,325,922 11.82 % $ 785,338 7.00 % N/A N/A First Financial Bank 1,452,403 12.95 % 784,807 7.00 % $ 728,749 6.50 % Tier 1 capital to risk-weighted assets Consolidated 1,368,818 12.20 % 953,625 8.50 % N/A N/A First Financial Bank 1,452,507 12.96 % 952,980 8.50 % 896,922 8.00 % Total capital to risk-weighted assets Consolidated 1,744,802 15.55 % 1,178,007 10.50 % N/A N/A First Financial Bank 1,560,457 13.92 % 1,177,211 10.50 % 1,121,153 10.00 % Leverage Consolidated 1,368,818 9.55 % 573,526 4.00 % N/A N/A First Financial Bank 1,452,507 10.14 % 573,094 4.00 % 716,367 5.00 % Actual Minimum capital PCA requirement to be (Dollars in thousands) Capital Ratio Capital Ratio Capital Ratio December 31, 2019 Common equity tier 1 capital to risk-weighted assets Consolidated $ 1,245,746 11.30 % $ 771,666 7.00 % N/A N/A First Financial Bank 1,333,978 12.11 % 770,997 7.00 % $ 715,926 6.50 % Tier 1 capital to risk-weighted assets Consolidated 1,288,185 11.69 % 937,023 8.50 % N/A N/A First Financial Bank 1,334,082 12.11 % 936,211 8.50 % 881,140 8.00 % Total capital to risk-weighted assets Consolidated 1,475,813 13.39 % 1,157,498 10.50 % N/A N/A First Financial Bank 1,399,817 12.71 % 1,156,496 10.50 % 1,101,425 10.00 % Leverage Consolidated 1,288,185 9.58 % 537,606 4.00 % N/A N/A First Financial Bank 1,334,082 9.93 % 537,299 4.00 % 671,623 5.00 %

STOCK OPTIONS AND AWARDS (Table

STOCK OPTIONS AND AWARDS (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Option, Activity [Table Text Block]		Stock option activity for the year ended December 31, 2020, is summarized as follows: (Dollars in thousands, except share and per share data) Number of shares Weighted Weighted average Aggregate intrinsic value Outstanding at beginning of year 37,856 $ 9.54 Granted 0 0.00 Exercised (10,405) 6.92 Forfeited or expired 0 0.00 Outstanding at end of year 27,451 $ 10.53 2.53 years $ 192 Exercisable at end of year 27,451 $ 10.53 2.53 years $ 192
Cash Proceeds Received and Tax Benefit from Share-based Payment Awards [Table Text Block]	2020 2019 2018 Total intrinsic value of options exercised $ 86 $ 462 $ 734 Cash received from exercises $ 72 $ 90 $ 284 Tax benefit from exercises $ 1,776 $ 1,844 $ 1,439
Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]		Activity in restricted stock for the previous three years ended December 31 is summarized as follows: 2020 2019 2018 Number of shares Weighted Number of shares Weighted Number of shares Weighted Nonvested at beginning of year 530,569 $ 27.19 462,446 $ 26.39 468,372 $ 21.63 Granted 503,311 18.62 395,023 26.55 303,930 28.94 Vested (233,828) 26.07 (295,633) 24.94 (267,031) 20.94 Forfeited (36,769) 23.79 (31,267) 28.63 (42,825) 26.38 Nonvested at end of year 763,283 $ 22.04 530,569 $ 27.19 462,446 $ 26.39

EARNINGS PER COMMON SHARE (Tabl

EARNINGS PER COMMON SHARE (Tables)	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share: (Dollars in thousands, except share and per share data) 2020 2019 2018 Numerator Net income $ 155,810 $ 198,075 $ 172,595 Denominator Basic earnings per common share - weighted average shares 97,363,952 98,305,570 88,582,090 Effect of dilutive securities Employee stock awards 729,146 545,901 514,680 Warrants 0 0 517,435 Diluted earnings per common share - adjusted weighted average shares 98,093,098 98,851,471 89,614,205 Earnings per share available to common shareholders Basic $ 1.60 $ 2.01 $ 1.95 Diluted $ 1.59 $ 2.00 $ 1.93

FAIR VALUE DISCLOSURES (Tables)

FAIR VALUE DISCLOSURES (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Estimated Fair Values of Financial Instruments	The estimated fair values of First Financial's financial instruments not measured at fair value on a recurring or nonrecurring basis in the consolidated financial statements were as follows: Carrying Estimated fair value (Dollars in thousands) value Total Level 1 Level 2 Level 3 December 31, 2020 Financial assets Cash and short-term investments $ 251,359 $ 251,359 $ 251,359 $ 0 $ 0 Investment securities held-to-maturity 131,687 136,698 0 136,698 0 Other investments 133,198 133,198 837 122,953 9,408 Loans and leases 9,725,291 9,743,497 0 0 9,743,497 Accrued interest receivable 50,903 50,903 0 13,221 37,682 Financial liabilities Deposits 12,232,003 12,238,058 0 12,238,058 0 Short-term borrowings 166,594 166,594 166,594 0 0 Long-term debt 776,202 774,674 0 774,674 0 Accrued interest payable 6,240 6,240 14 6,226 0 Carrying Estimated Fair Value (Dollars in thousands) Value Total Level 1 Level 2 Level 3 December 31, 2019 Financial assets Cash and short-term investments $ 257,639 $ 257,639 $ 257,639 $ 0 $ 0 Investment securities held-to-maturity 142,862 142,821 0 142,821 0 Other investments 125,020 125,020 699 123,821 500 Loans and leases 9,144,015 9,134,215 0 0 9,134,215 Accrued interest receivable 39,591 39,591 0 12,743 26,848 Financial liabilities Deposits 10,210,229 10,209,790 0 10,209,790 0 Short-term borrowings 1,316,181 1,316,181 1,316,181 0 0 Long-term debt 414,376 414,937 0 414,937 0 Accrued interest payable 13,671 13,671 1,899 11,772 0
Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	The financial assets and liabilities measured at fair value on a recurring basis, including those for which we elected the fair value option, were as follows: Fair Value Measurements Using Assets/Liabilities (Dollars in thousands) Level 1 Level 2 Level 3 at Fair Value December 31, 2020 Assets Investment securities available-for-sale $ 103 $ 3,383,902 $ 40,575 $ 3,424,580 Loans held for sale 0 41,103 0 41,103 Interest rate derivative contracts 0 185,032 0 185,032 Foreign exchange derivative contracts 0 87,615 0 87,615 Total $ 103 $ 3,697,652 $ 40,575 $ 3,738,330 Liabilities Interest rate derivative contracts $ 0 $ 186,124 $ 0 $ 186,124 Foreign exchange derivative contracts 0 87,615 0 87,615 Total $ 0 $ 273,739 $ 0 $ 273,739 Fair Value Measurements Using Assets/Liabilities (Dollars in thousands) Level 1 Level 2 Level 3 at Fair Value December 31, 2019 Assets Investment securities available-for-sale $ 100 $ 2,842,794 $ 9,190 $ 2,852,084 Loans held for sale 0 13,680 0 13,680 Interest rate derivative contracts 0 73,558 0 73,558 Foreign exchange derivative contracts 0 39,172 0 39,172 Total $ 100 $ 2,969,204 $ 9,190 $ 2,978,494 Liabilities Interest rate derivative contracts $ 0 $ 73,750 $ 0 $ 73,750 Foreign exchange derivative contracts 0 39,172 0 39,172 Total $ 0 $ 112,922 $ 0 $ 112,922
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The following table presents a reconciliation for certain AFS securities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the year ended December 31, 2020. (dollars in thousands) December 31, 2020 December 31, 2019 Beginning balance $ 9,190 $ 14,715 Accretion (amortization) 1 (552) Increase (decrease) in fair value (17) 30 Purchases (settlements) 31,401 (5,003) Ending balance $ 40,575 $ 9,190
Summary of Financial Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis	The following table summarizes financial assets and liabilities measured at fair value on a nonrecurring basis: Fair Value Measurements Using (Dollars in thousands) Level 1 Level 2 Level 3 December 31, 2020 Assets Collateral dependent loans Commercial $ 0 $ 0 $ 25,367 Commercial real estate 0 0 6,432 OREO 0 0 54 Fair Value Measurements Using (Dollars in thousands) Level 1 Level 2 Level 3 December 31, 2019 Assets Collateral dependent loans Commercial $ 0 $ 0 $ 8,710 Commercial real estate 0 0 558 OREO 0 0 1,088

BUSINESS COMBINATIONS (Tables)

BUSINESS COMBINATIONS (Tables)	6 Months Ended
	Jun. 30, 2020
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table provides the purchase price calculation as of the acquisition date, identifiable assets purchased and liabilities assumed at their estimated fair value for the MSFG merger. As a condition of the merger, certain acquired assets and liabilities held for sale were divested subsequent to the closing of the merger. There was no gain or loss recorded in the Consolidated Statement of Income in conjunction with this divestiture. (Dollars in thousands) MainSource Purchase consideration Cash consideration $ 43 Stock consideration 1,043,424 Warrant consideration 14,460 Options consideration 1,577 Total purchase consideration 1,059,504 Assets acquired Cash 71,806 Investment securities available-for-sale 900,935 Investment securities held-to-maturity 171,423 Other investments 28,763 Loans 2,792,572 Premises and equipment 98,814 Intangible assets 42,887 Other assets 167,829 Assets held for sale 127,775 Total assets acquired 4,402,804 Liabilities assumed Deposits 3,263,920 Subordinated notes 49,027 FHLB advances 291,887 Other borrowings 205,620 Other liabilities 32,649 Liabilities held for sale 175,840 Total liabilities assumed 4,018,943 Net identifiable assets 383,861 Goodwill $ 675,643
Business Acquisition, Pro Forma Information, Nonrecurring Adjustments	Twelve months ended December 31, (Dollars in thousands, except per share data) (Unaudited) 2018 2017 Pro Forma Condensed Combined Income Statement Information Net interest income $ 484,915 $ 454,579 Net income $ 221,122 $ 130,402 Basic earnings per share $ 2.27 $ 1.34 Diluted earnings per share $ 2.25 $ 1.33

FIRST FINANCIAL BANCORP. (PAR_2

FIRST FINANCIAL BANCORP. (PARENT COMPANY ONLY) FINANCIAL INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2020
Condensed Financial Information Disclosure [Abstract]
Schedule of Condensed Balance Sheet	Balance Sheets December 31, (Dollars in thousands) 2020 2019 Assets Cash $ 172,902 $ 55,869 Investment securities 1,388 1,116 Subordinated notes from subsidiaries 7,500 7,500 Investment in subsidiaries Commercial bank 2,346,009 2,272,991 Non-banks 9,559 8,260 Total investment in subsidiaries 2,355,568 2,281,251 Premises and equipment 1,328 1,344 Other assets 68,812 77,572 Total assets $ 2,607,498 $ 2,424,652 Liabilities Subordinated notes $ 320,615 $ 171,983 Dividends payable 674 849 Other liabilities 4,139 4,115 Total liabilities 325,428 176,947 Shareholders’ equity 2,282,070 2,247,705 Total liabilities and shareholders’ equity $ 2,607,498 $ 2,424,652
Schedule of Condensed Income Statement	Statements of Income and Comprehensive Income Years Ended December 31, (Dollars in thousands) 2020 2019 2018 Income Interest income $ 27 $ 30 $ 23 Noninterest income 272 191 0 Dividends from subsidiaries 81,725 196,800 107,340 Total income 82,024 197,021 107,363 Expenses Interest expense 14,172 9,552 8,798 Salaries and employee benefits 8,004 8,169 6,413 Professional services 1,160 1,040 5,130 Other 5,163 6,599 5,648 Total expenses 28,499 25,360 25,989 Income before income taxes and equity in undistributed net earnings of subsidiaries 53,525 171,661 81,374 Income tax expense (benefit) (6,145) (5,975) (6,687) Equity in undistributed earnings (loss) of subsidiaries 96,140 20,439 84,534 Net income $ 155,810 $ 198,075 $ 172,595 Comprehensive income $ 191,151 $ 254,900 $ 153,670
Schedule of Condensed Cash Flow Statement	Statements of Cash Flows Years Ended December 31, (Dollars in thousands) 2020 2019 2018 Operating activities Net income $ 155,810 $ 198,075 $ 172,595 Adjustments to reconcile net income to net cash provided by operating activities Equity in undistributed (earnings) loss of subsidiaries (96,140) (20,439) (84,534) Depreciation and amortization 712 584 194 Stock-based compensation expense 7,678 7,969 6,219 Deferred income taxes (158) 1,255 739 (Decrease) increase in dividends payable (175) 384 (10,500) (Decrease) increase in other liabilities (22) (244) 9,979 Decrease (increase) in other assets 8,635 (7,187) 16,346 Net cash provided by (used in) operating activities 76,340 180,397 111,038 Investing activities Capital contributions to subsidiaries 0 0 (3,000) Net cash acquired (paid) in business combinations 0 (53,660) 11,353 Proceeds from sales and maturities of investment securities 0 264 0 Purchases of investment securities 0 (500) 0 Net cash (used in) provided by investing activities 0 (53,896) 8,353 Financing activities (Decrease) increase in short-term borrowings 0 0 (8,333) Proceeds from long-term borrowings 150,000 0 0 Cash dividends paid on common stock (89,691) (89,097) (79,655) Purchases of common stock (16,686) (66,218) 0 Proceeds from exercise of stock options, net of shares purchased 72 90 284 Other (3,002) (2,285) (2,528) Net cash provided by (used in) financing activities 40,693 (157,510) (90,232) Net increase (decrease) in cash 117,033 (31,009) 29,159 Cash at beginning of year 55,869 86,878 57,719 Cash at end of year $ 172,902 $ 55,869 $ 86,878

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Financing Receivables (Details)	12 Months Ended
	Dec. 31, 2020USD ($)
Commercial & Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured Loans, Loan Relationships, Review Threshold Amount Minimum	$ 250,000

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Premises and Equipment (Details)	12 Months Ended
	Dec. 31, 2020
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	20 years
Minimum | Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Minimum | Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Minimum | Software, Hardware, and Data Handling Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Maximum | Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Maximum | Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Maximum | Software, Hardware, and Data Handling Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Interest Receivable (Details) $ in Thousands	Dec. 31, 2020USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 37,682
Held-to-maturity Securities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	300
Available-for-sale Securities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 12,900

RECENTLY ADOPTED AND ISSUED A_3

RECENTLY ADOPTED AND ISSUED ACCOUNTING STANDARDS - Additional Information (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	$ 61,505	$ 61,505
Off-Balance Sheet, Credit Loss, Liability, Change in Method, Credit Loss Expense (Reversal)	12,155	12,200
Deferred tax liability, Credit Loss, Change in Method, Credit Loss Expense (Reversal)	$ (16,778)
Cumulative Effect, Period of Adoption, Adjustment
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			$ (56,882)	$ 3,542	$ 0
Retained earnings | Cumulative Effect, Period of Adoption, Adjustment
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ 56,900	$ (56,882)	$ 2,636	$ 5,093

RECENTLY ADOPTED AND ISSUED A_4

RECENTLY ADOPTED AND ISSUED ACCOUNTING STANDARDS ASC 326 (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable, Allowance	$ 119,155	$ 175,679	$ 57,650	$ 56,542	$ 54,021
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	61,505	61,505
Deferred Tax Liabilities, Deferred Expense	16,252		33,030
Deferred tax liability, Credit Loss, Change in Method, Credit Loss Expense (Reversal)	(16,778)
Off-Balance Sheet, Credit Loss, Liability	12,740		585
Off-Balance Sheet, Credit Loss, Liability, Change in Method, Credit Loss Expense (Reversal)	12,155	12,200
Commercial & Industrial
Loans and Leases Receivable, Allowance	28,485	51,454	18,584	18,746	17,598
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	9,901	9,901
Lease financing
Loans and Leases Receivable, Allowance	1,089	995	971	1,130	675
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	118	118
Construction real estate
Loans and Leases Receivable, Allowance	13,960	21,736	2,381	3,413	3,577
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	11,579	11,579
Commercial real estate
Loans and Leases Receivable, Allowance	47,697	76,795	23,579	21,048	20,930
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	24,118	24,118
Residential real estate
Loans and Leases Receivable, Allowance	10,789	8,560	5,299	4,964	4,683
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	5,490	5,490
Home equity
Loans and Leases Receivable, Allowance	13,217	11,869	4,787	5,348	4,935
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	8,430	8,430
Installment
Loans and Leases Receivable, Allowance	1,193	1,215	392	362	307
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	801	801
Credit card
Loans and Leases Receivable, Allowance	2,725	3,055	$ 1,657	$ 1,531	$ 1,316
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	$ 1,068	$ 1,068

RESTRICTIONS ON CASH AND DIVI_2

RESTRICTIONS ON CASH AND DIVIDENDS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Restrictions on Subsidiary Dividends, Loans or Advances [Line Items]
Average Restriction on Cash and Due From Bank Accounts	$ 0	$ 84.1
Restricted Cash	38	$ 15.8
Subsidiaries [Member]
Restrictions on Subsidiary Dividends, Loans or Advances [Line Items]
Retained Earnings, Unappropriated	700
Amount Available for Dividend Distribution without Affecting Capital Adequacy Requirements	$ 198

INVESTMENT SECURITIES INVESTMEN

INVESTMENT SECURITIES INVESTMENTS - Additional Information (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Gain (Loss) on Securities [Line Items]
Proceeds from Sale of Debt Securities, Available-for-sale			$ 117,800	$ 519,100	$ 290,700
Available-for-sale Securities, Gross Realized Gains			900	2,100	500
Available-for-sale Securities, Gross Realized Losses			800	2,100	600
Available For Sale Securities Net Realized Gain Loss Tax Provision			19	(7)	37
Securities transferred from HTM to AFS	$ 268,700	$ 372,100	0	268,703	$ 372,128
Realized gain (loss) on debt securities transferred from HTM to AFS	$ 200
Pledged Financial Instruments, Not Separately Reported, Securities			$ 1,500,000	$ 1,100,000
NumberOfSecuritiesInSecurityPortfolio			1,351	1,273
NumberOfSecuritiesInUnrealizedLossPosition			94	140
Debt Securities, Held-to-maturity, Allowance for Credit Loss			$ 0
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings				$ 0

INVESTMENTS - Summary of Held-T

INVESTMENTS - Summary of Held-To-Maturity and Available-For-Sale Investment Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Investment Holdings [Line Items]
Total	$ 131,687	$ 142,862
Held To Maturity unrecognized gain	5,011	1,497
Held To Maturity unrecognized loss	0	1,538
Held-to-Maturity Market Value	136,698	142,821
Total	3,330,029	2,798,298
Available for Sale unrecognized gain	99,942	58,555
Available for Sale unrecognized loss	5,391	4,769
Investment securities	3,424,580	2,852,084
U.S. Treasuries
Investment Holdings [Line Items]
Total	0	0
Held To Maturity unrecognized gain	0	0
Held To Maturity unrecognized loss	0	0
Held-to-Maturity Market Value	0	0
Investment securities	103	100
Debt Securities, Available-for-sale, Amortized Cost	99	99
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	4	1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Securities of U.S. government agencies and corporations
Investment Holdings [Line Items]
Total	0	0
Held To Maturity unrecognized gain	0	0
Held To Maturity unrecognized loss	0	0
Held-to-Maturity Market Value	0	0
Investment securities	60	158
Debt Securities, Available-for-sale, Amortized Cost	60	156
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	2
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Mortgage-backed securities-residential
Investment Holdings [Line Items]
Total	13,990	20,818
Held To Maturity unrecognized gain	197	122
Held To Maturity unrecognized loss	0	174
Held-to-Maturity Market Value	14,187	20,766
Total	704,482
Investment securities	720,183	431,555
Debt Securities, Available-for-sale, Amortized Cost	704,482	421,945
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	15,938	9,709
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(237)	(99)
Mortgage-backed securities-commercial
Investment Holdings [Line Items]
Total	71,737	101,267
Held To Maturity unrecognized gain	3,485	571
Held To Maturity unrecognized loss	0	1,225
Held-to-Maturity Market Value	75,222	100,613
Total	584,125
Investment securities	590,936	476,518
Debt Securities, Available-for-sale, Amortized Cost	584,125	474,174
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	10,395	4,988
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(3,584)	(2,644)
Collateralized mortgage obligations
Investment Holdings [Line Items]
Total	5,799	9,763
Held To Maturity unrecognized gain	79	0
Held To Maturity unrecognized loss	0	108
Held-to-Maturity Market Value	5,878	9,655
Total	634,418
Investment securities	655,121	785,444
Debt Securities, Available-for-sale, Amortized Cost	634,418	769,076
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	21,148	16,753
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(445)	(385)
Obligations of state and other political subdivisions
Investment Holdings [Line Items]
Total	9,911	11,014
Held To Maturity unrecognized gain	1,239	804
Held To Maturity unrecognized loss	0	31
Held-to-Maturity Market Value	11,150	11,787
Investment securities	902,518	676,253
Debt Securities, Available-for-sale, Amortized Cost	856,054	652,986
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	46,755	23,729
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(291)	(462)
Asset-backed Securities
Investment Holdings [Line Items]
Total	0	0
Held To Maturity unrecognized gain	0	0
Held To Maturity unrecognized loss	0	0
Held-to-Maturity Market Value	0	0
Total	478,539
Investment securities	481,871	400,431
Debt Securities, Available-for-sale, Amortized Cost	478,539	400,081
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	4,158	1,414
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(826)	(1,064)
Other securities
Investment Holdings [Line Items]
Total	30,250	0
Held To Maturity unrecognized gain	11	0
Held To Maturity unrecognized loss	0	0
Held-to-Maturity Market Value	30,261	0
Investment securities	73,788	81,625
Debt Securities, Available-for-sale, Amortized Cost	72,252	79,781
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,544	1,959
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	$ (8)	$ (115)

INVESTMENTS - Summary of Invest

INVESTMENTS - Summary of Investment Securities by Estimated Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Held-to-Maturity Amortized Cost
Amortized cost	$ 131,687	$ 142,862
Held-to-Maturity Market Value
Held-to-Maturity Market Value	136,698	142,821
Available-for-Sale Amortized Cost
Amortized Cost	3,330,029	2,798,298
Available-for-Sale Market Value
Investment securities	3,424,580	2,852,084
One Year or Less
Held-to-Maturity Amortized Cost
Amortized cost	0
Held-to-Maturity Market Value
Held-to-Maturity Market Value	0
Available-for-Sale Amortized Cost
Amortized Cost	5,745
Available-for-Sale Market Value
Investment securities	5,802
After One Year Through Five Years
Held-to-Maturity Amortized Cost
Amortized cost	0
Held-to-Maturity Market Value
Held-to-Maturity Market Value	0
Available-for-Sale Amortized Cost
Amortized Cost	62,930
Available-for-Sale Market Value
Investment securities	64,886
After Five Years Through Ten Years
Held-to-Maturity Amortized Cost
Amortized cost	36,084
Held-to-Maturity Market Value
Held-to-Maturity Market Value	37,205
Available-for-Sale Amortized Cost
Amortized Cost	161,307
Available-for-Sale Market Value
Investment securities	169,692
After Ten Years
Held-to-Maturity Amortized Cost
Amortized cost	4,077
Held-to-Maturity Market Value
Held-to-Maturity Market Value	4,206
Available-for-Sale Amortized Cost
Amortized Cost	698,483
Available-for-Sale Market Value
Investment securities	736,089
Mortgage-backed securities-residential
Held-to-Maturity Amortized Cost
Amortized cost	13,990	20,818
Held-to-Maturity Market Value
Held-to-Maturity Market Value	14,187	20,766
Available-for-Sale Amortized Cost
Amortized Cost	704,482
Available-for-Sale Market Value
Investment securities	720,183	431,555
Mortgage-backed securities-commercial
Held-to-Maturity Amortized Cost
Amortized cost	71,737	101,267
Held-to-Maturity Market Value
Held-to-Maturity Market Value	75,222	100,613
Available-for-Sale Amortized Cost
Amortized Cost	584,125
Available-for-Sale Market Value
Investment securities	590,936	476,518
Collateralized mortgage obligations
Held-to-Maturity Amortized Cost
Amortized cost	5,799	9,763
Held-to-Maturity Market Value
Held-to-Maturity Market Value	5,878	9,655
Available-for-Sale Amortized Cost
Amortized Cost	634,418
Available-for-Sale Market Value
Investment securities	655,121	785,444
Asset-backed Securities
Held-to-Maturity Amortized Cost
Amortized cost	0	0
Held-to-Maturity Market Value
Held-to-Maturity Market Value	0	0
Available-for-Sale Amortized Cost
Amortized Cost	478,539
Available-for-Sale Market Value
Investment securities	$ 481,871	$ 400,431

INVESTMENTS - Age of Gross Unre

INVESTMENTS - Age of Gross Unrealized Losses and Associated Fair Value by Investment Category (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Investments, Unrealized Loss Position [Line Items]
Document Period End Date	Dec. 31, 2020
Less than 12 Months Fair Value	$ 426,607	$ 481,608
Less than 12 Months Unrealized Loss	(2,402)	(1,814)
12 Months or More Fair Value	117,126	214,322
12 Months or More Unrealized Loss	(2,989)	(4,493)
Total Fair Value	543,733	695,930
Total Unrealized Loss	(5,391)	(6,307)
U.S. Treasuries
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	0	0
Less than 12 Months Unrealized Loss	0	0
12 Months or More Fair Value	0	0
12 Months or More Unrealized Loss	0	0
Total Fair Value	0	0
Total Unrealized Loss	0	0
Securities of U.S. government agencies and corporations
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	0	0
Less than 12 Months Unrealized Loss	0	0
12 Months or More Fair Value	0	0
12 Months or More Unrealized Loss	0	0
Total Fair Value	0	0
Total Unrealized Loss	0	0
Mortgage-backed securities-residential
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	57,872	40,190
Less than 12 Months Unrealized Loss	(237)	(209)
12 Months or More Fair Value	0	11,063
12 Months or More Unrealized Loss	0	(64)
Total Fair Value	57,872	51,253
Total Unrealized Loss	(237)	(273)
Mortgage-backed securities-commercial
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	169,825	111,658
Less than 12 Months Unrealized Loss	(986)	(298)
12 Months or More Fair Value	48,158	104,069
12 Months or More Unrealized Loss	(2,598)	(3,571)
Total Fair Value	217,983	215,727
Total Unrealized Loss	(3,584)	(3,869)
Collateralized mortgage obligations
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	49,161	85,248
Less than 12 Months Unrealized Loss	(445)	(297)
12 Months or More Fair Value	1	30,628
12 Months or More Unrealized Loss	0	(196)
Total Fair Value	49,162	115,876
Total Unrealized Loss	(445)	(493)
Obligations of state and other political subdivisions
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	60,008	118,623
Less than 12 Months Unrealized Loss	(291)	(457)
12 Months or More Fair Value	0	7,950
12 Months or More Unrealized Loss	0	(36)
Total Fair Value	60,008	126,573
Total Unrealized Loss	(291)	(493)
Asset-backed Securities
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	84,749	125,889
Less than 12 Months Unrealized Loss	(435)	(553)
12 Months or More Fair Value	68,967	54,963
12 Months or More Unrealized Loss	(391)	(511)
Total Fair Value	153,716	180,852
Total Unrealized Loss	(826)	(1,064)
Other securities
Investments, Unrealized Loss Position [Line Items]
Less than 12 Months Fair Value	4,992	0
Less than 12 Months Unrealized Loss	(8)	0
12 Months or More Fair Value	0	5,649
12 Months or More Unrealized Loss	0	(115)
Total Fair Value	4,992	5,649
Total Unrealized Loss	$ (8)	$ (115)

LOANS - Additional Information

LOANS - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)loans	Dec. 31, 2019USD ($)loans	Dec. 31, 2018USD ($)loans	Dec. 31, 2017USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Restructured Loans | loans	155	157	196
Total restructured loans	$ 21,800	$ 30,000	$ 38,500
Restructured Loans, Accrual Status	7,100	11,400	16,100
Restructured Loans, Nonaccrual Status	14,700	18,500	22,400
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	300	2,500	0
Restructured Loans, Allowance for Loan and Lease Losses Included in Reserves	8,800	2,500	1,500
Restructured Loans, Portion Determined to be Uncollectible	1,700	2,600	900
Accruing TDRs performing in accordance with restructured terms for more than one year	5,000	4,700	7,900
Purchased impaired loans, carrying balance		68,664
Real Estate Acquired Through Foreclosure	1,287	2,033	$ 1,401	$ 2,781
Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchased impaired loans, carrying balance		$ 3,081
Paycheck Protection Program Amount of Funding	594,600
Unearned fees	$ 13,700

LOANS - Commercial and Consumer

LOANS - Commercial and Consumer Credit Exposure by Risk Attribute (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 2,378,125
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,239,068
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,303,349
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	935,938
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	687,912
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,075,362
Financing Receivable, before Allowance for Credit Loss	8,619,754
Financing Receivable, Revolving	1,281,216
Loans and Leases Receivable, Net of Deferred Income	9,900,970	$ 9,201,665
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		7,011,217
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		160,825
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		70,032
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Commercial & Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		2,465,877
Commercial & Industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		2,324,021
Commercial & Industrial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		100,954
Commercial & Industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		40,902
Commercial & Industrial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Construction real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		493,182
Construction real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		493,182
Construction real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Construction real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Construction real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Commercial real estate-investor
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		4,194,651
Commercial real estate-investor | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		4,108,752
Commercial real estate-investor | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		59,383
Commercial real estate-investor | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		26,516
Commercial real estate-investor | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Lease financing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		88,364
Lease financing | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		85,262
Lease financing | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		488
Lease financing | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		2,614
Lease financing | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		0
Total commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income	45,456	7,242,074
Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		1,055,949
Residential real estate | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		1,040,787
Residential real estate | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		15,162
Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		771,869
Home equity | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		766,169
Home equity | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		5,700
Installment
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income	163	82,589
Installment | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		82,385
Installment | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		204
Credit card
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		49,184
Credit card | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		48,983
Credit card | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		201
Total consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		1,959,591
Total consumer loans | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		1,938,324
Total consumer loans | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Net of Deferred Income		21,267
Total commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,172,540
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	472,861
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	322,361
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	241,535
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	134,478
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	145,589
Financing Receivable, before Allowance for Credit Loss	2,489,364
Financing Receivable, Revolving	518,145
Loans and Leases Receivable, Net of Deferred Income	3,007,509	2,465,877
Total commercial loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	1,141,163
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	460,210
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	296,221
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	208,077
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	122,686
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	138,307
Financing Receivable, before Allowance for Credit Loss	2,366,664
Financing Receivable, Revolving	502,286
Loans and Leases Receivable, Net of Deferred Income	2,868,950
Total commercial loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	24,668
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	10,281
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	18,118
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	6,893
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	6,668
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	6,090
Financing Receivable, before Allowance for Credit Loss	72,718
Financing Receivable, Revolving	10,470
Loans and Leases Receivable, Net of Deferred Income	83,188
Total commercial loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	6,709
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,370
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	8,022
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	26,565
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	5,124
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,192
Financing Receivable, before Allowance for Credit Loss	49,982
Financing Receivable, Revolving	5,389
Loans and Leases Receivable, Net of Deferred Income	55,371
Total commercial loans | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	0
Lease financing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	23,211
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	22,397
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	12,942
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	7,147
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,922
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,368
Financing Receivable, before Allowance for Credit Loss	72,987
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	72,987	88,364
Lease financing | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	22,916
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	22,397
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	12,942
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	6,967
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,802
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,368
Financing Receivable, before Allowance for Credit Loss	72,392
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	72,392
Lease financing | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	290
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	290
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	290
Lease financing | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	5
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	180
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	120
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	305
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	305
Lease financing | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	0
Construction real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	96,410
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	260,145
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	200,828
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	33,169
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	25,447
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	426
Financing Receivable, before Allowance for Credit Loss	616,425
Financing Receivable, Revolving	19,671
Loans and Leases Receivable, Net of Deferred Income	636,096	493,182
Construction real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	96,410
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	259,524
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	182,625
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	23,185
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	24,786
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	426
Financing Receivable, before Allowance for Credit Loss	586,956
Financing Receivable, Revolving	19,671
Loans and Leases Receivable, Net of Deferred Income	606,627
Construction real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	621
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	18,203
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	9,984
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	661
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	29,469
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	29,469
Construction real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	0
Construction real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	0
Commercial real estate-investor
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	522,148
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,031,404
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	465,108
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	430,029
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	319,063
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	419,831
Financing Receivable, before Allowance for Credit Loss	3,187,583
Financing Receivable, Revolving	56,957
Loans and Leases Receivable, Net of Deferred Income	3,244,540
Commercial real estate-investor | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	515,950
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,011,898
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	427,077
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	378,536
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	286,587
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	361,403
Financing Receivable, before Allowance for Credit Loss	2,981,451
Financing Receivable, Revolving	56,398
Loans and Leases Receivable, Net of Deferred Income	3,037,849
Commercial real estate-investor | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	17,463
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	15,534
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	44,426
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	32,408
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	43,704
Financing Receivable, before Allowance for Credit Loss	153,535
Financing Receivable, Revolving	559
Loans and Leases Receivable, Net of Deferred Income	154,094
Commercial real estate-investor | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	6,198
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,043
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	22,497
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	7,067
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	68
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	14,724
Financing Receivable, before Allowance for Credit Loss	52,597
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	52,597
Commercial real estate-investor | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	0
Commercial real estate-owner
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	190,652
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	174,364
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	157,181
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	139,001
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	132,078
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	233,224
Financing Receivable, before Allowance for Credit Loss	1,026,500
Financing Receivable, Revolving	36,818
Loans and Leases Receivable, Net of Deferred Income	1,063,318
Commercial real estate-owner | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	185,692
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	162,480
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	147,236
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	125,275
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	128,755
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	211,519
Financing Receivable, before Allowance for Credit Loss	960,957
Financing Receivable, Revolving	36,721
Loans and Leases Receivable, Net of Deferred Income	997,678
Commercial real estate-owner | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	4,292
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	11,380
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,891
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	8,230
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	3,017
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	19,384
Financing Receivable, before Allowance for Credit Loss	49,194
Financing Receivable, Revolving	59
Loans and Leases Receivable, Net of Deferred Income	49,253
Commercial real estate-owner | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	668
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	504
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	7,054
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	5,496
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	306
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	2,321
Financing Receivable, before Allowance for Credit Loss	16,349
Financing Receivable, Revolving	38
Loans and Leases Receivable, Net of Deferred Income	16,387
Commercial real estate-owner | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	0
Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	60,967
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	20,200
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	17,445
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	11,347
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	9,772
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	41,709
Financing Receivable, before Allowance for Credit Loss	161,440
Financing Receivable, Revolving	581,659
Loans and Leases Receivable, Net of Deferred Income	743,099	771,869
Home equity | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	60,967
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	20,200
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	17,445
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	11,308
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	9,744
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	41,571
Financing Receivable, before Allowance for Credit Loss	161,235
Financing Receivable, Revolving	577,609
Loans and Leases Receivable, Net of Deferred Income	738,844
Home equity | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	39
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	28
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	138
Financing Receivable, before Allowance for Credit Loss	205
Financing Receivable, Revolving	4,050
Loans and Leases Receivable, Net of Deferred Income	4,255
Total consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	21,599
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	15,667
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	11,064
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	8,847
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,971
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	3,221
Financing Receivable, before Allowance for Credit Loss	62,369
Financing Receivable, Revolving	19,481
Loans and Leases Receivable, Net of Deferred Income	81,850	82,589
Total consumer loans | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	21,584
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	15,614
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	11,041
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	8,812
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,954
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	3,185
Financing Receivable, before Allowance for Credit Loss	62,190
Financing Receivable, Revolving	19,479
Loans and Leases Receivable, Net of Deferred Income	81,669
Total consumer loans | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	15
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	53
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	23
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	35
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	17
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	36
Financing Receivable, before Allowance for Credit Loss	179
Financing Receivable, Revolving	2
Loans and Leases Receivable, Net of Deferred Income	181
Credit card
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	48,485
Loans and Leases Receivable, Net of Deferred Income	48,485	49,184
Credit card | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	47,845
Loans and Leases Receivable, Net of Deferred Income	47,845
Credit card | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	0
Financing Receivable, before Allowance for Credit Loss	0
Financing Receivable, Revolving	640
Loans and Leases Receivable, Net of Deferred Income	640
Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	290,598
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	242,030
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	116,420
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	64,863
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	60,181
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	228,994
Financing Receivable, before Allowance for Credit Loss	1,003,086
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	1,003,086	$ 1,055,949
Residential real estate | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	290,277
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	241,601
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	115,747
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	64,220
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	60,094
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	224,281
Financing Receivable, before Allowance for Credit Loss	996,220
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	996,220
Residential real estate | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	321
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	429
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	673
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	643
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	87
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	4,713
Financing Receivable, before Allowance for Credit Loss	6,866
Financing Receivable, Revolving	0
Loans and Leases Receivable, Net of Deferred Income	$ 6,866

LOANS - Loan Delinquency, inclu

LOANS - Loan Delinquency, including Nonaccrual Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	$ 51,946	$ 48,554
Current	9,849,024	9,084,447
Loans and Leases Receivable, Gross		9,133,001
Purchased impaired loans, carrying balance		68,664
Total loans and leases	9,900,970	9,201,665
Greater than 90 days past due and still accruing	169	201
30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	17,837	12,923
60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	1,577	7,325
Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	32,532	28,306
Commercial & industrial
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	8,393	19,116
Current	2,999,116	2,443,680
Loans and Leases Receivable, Gross		2,462,796
Purchased impaired loans, carrying balance		3,081
Total loans and leases	3,007,509	2,465,877
Greater than 90 days past due and still accruing	0	0
Commercial & industrial | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	6,532	1,266
Commercial & industrial | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	3,332
Commercial & industrial | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	1,861	14,518
Lease financing
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Current	72,987	88,364
Loans and Leases Receivable, Gross		88,364
Purchased impaired loans, carrying balance		0
Total loans and leases	72,987	88,364
Greater than 90 days past due and still accruing	0	0
Lease financing | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Lease financing | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Lease financing | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Construction real estate
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Current	636,096	493,167
Loans and Leases Receivable, Gross		493,167
Purchased impaired loans, carrying balance		15
Total loans and leases	636,096	493,182
Greater than 90 days past due and still accruing	0	0
Construction real estate | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Construction real estate | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Construction real estate | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0	0
Commercial real estate-investor
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	24,558
Current	3,219,982
Total loans and leases	3,244,540
Greater than 90 days past due and still accruing	0
Commercial real estate-investor | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	136
Commercial real estate-investor | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	0
Commercial real estate-investor | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	24,422
Commercial real estate-owner
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	7,054
Current	1,056,264
Total loans and leases	1,063,318
Greater than 90 days past due and still accruing	0
Commercial real estate-owner | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	6,480
Commercial real estate-owner | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	174
Commercial real estate-owner | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	400
Commercial real estate
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due		7,246
Current		4,151,513
Loans and Leases Receivable, Gross		4,158,759
Purchased impaired loans, carrying balance		35,892
Total loans and leases	4,307,858	4,194,651
Greater than 90 days past due and still accruing		0
Commercial real estate | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due		776
Commercial real estate | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due		857
Commercial real estate | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due		5,613
Residential real estate
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	6,866	14,991
Current	996,220	1,014,138
Loans and Leases Receivable, Gross		1,029,129
Purchased impaired loans, carrying balance		26,820
Total loans and leases	1,003,086	1,055,949
Greater than 90 days past due and still accruing	0	0
Residential real estate | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	2,809	8,032
Residential real estate | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	370	1,928
Residential real estate | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	3,687	5,031
Home equity
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	4,255	6,408
Current	738,844	762,863
Loans and Leases Receivable, Gross		769,271
Purchased impaired loans, carrying balance		2,598
Total loans and leases	743,099	771,869
Greater than 90 days past due and still accruing	0	0
Home equity | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	1,483	2,530
Home equity | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	835	1,083
Home equity | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	1,937	2,795
Installment
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	180	309
Current	81,670	82,022
Loans and Leases Receivable, Gross		82,331
Purchased impaired loans, carrying balance		258
Total loans and leases	81,850	82,589
Greater than 90 days past due and still accruing	0	0
Installment | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	94	111
Installment | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	35	50
Installment | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	51	148
Credit card
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	640	484
Current	47,845	48,700
Loans and Leases Receivable, Gross		49,184
Purchased impaired loans, carrying balance		0
Total loans and leases	48,485	49,184
Greater than 90 days past due and still accruing	169	201
Credit card | 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	303	208
Credit card | 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	163	75
Credit card | Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Financing receivables, Past Due	$ 174	$ 201

LOANS - Restructured Loans (Det

LOANS - Restructured Loans (Details)	12 Months Ended
	Dec. 31, 2020USD ($)dentityloans	Dec. 31, 2019USD ($)loans	Dec. 31, 2018USD ($)loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extended Maturities	$ 0	$ 2,877,000	$ 4,093,000
Adjusted Interest Rates	0	5,284,000	52,000
Combined Rate And Maturity	0	516,000	0
Forebearance Agreements	4,759,000	20,320,000	23,175,000
Other	12,443,000	2,473,000	985,000
Total	$ 17,202,000	$ 31,470,000	$ 28,305,000
Number of Restructured Loans | loans	155	157	196
Restructured loans, Number of Loans | loans	45	63	43
Restructured loans, Restructured loans, Pre-Modification Loan Balance	$ 17,323,000	$ 31,884,000	$ 28,571,000
Restructured loans, Period End Balance	$ 17,202,000	$ 31,470,000	$ 28,305,000
Restructured loans with payment default within 12 months of modification, Number of Loans | loans	1	3	1
Restructured loans with payment default within 12 months of modification, Period End Balance	$ 29,000	$ 7,000,000	$ 41,000
Total restructured loans	21,800,000	30,000,000	38,500,000
Restructured Loans, Accrual Status	7,100,000	11,400,000	16,100,000
Restructured Loans, Nonaccrual Status	14,700,000	18,500,000	22,400,000
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	300,000	2,500,000	0
Restructured Loans, Allowance for Loan and Lease Losses Included in Reserves	8,800,000	2,500,000	1,500,000
Accruing TDRs performing in accordance with restructured terms for more than one year	$ 5,000,000	$ 4,700,000	$ 7,900,000
Restructured loans performance threshold (days) | d	90
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	$ 320,200,000
Payment Deferral [Member] | Loan Deferrals First Round [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	18,500,000
Payment Deferral [Member] | Loan Deferrals Second Round [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	54,900,000
Payment Deferral [Member] | Loan Deferrals Third Round [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	246,800,000
Payment Deferral [Member] | Interest only payments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	291,500,000
Payment Deferral [Member] | Full principal and Interest payments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	28,700,000
Commercial & Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured Loans, Loan Relationships, Review Threshold Amount Minimum	$ 250,000
Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured loans, Number of Loans | loans		8	17
Restructured loans, Restructured loans, Pre-Modification Loan Balance		$ 25,009,000	$ 23,943,000
Restructured loans, Period End Balance		$ 25,071,000	$ 23,890,000
Financing Receivable, Modifications, Number of Contracts | loans	8
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 14,984,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 14,984,000
Commercial & industrial | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Number of Contracts | entity	90
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	$ 312,500,000
Construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured loans, Number of Loans | loans		0	0
Restructured loans, Restructured loans, Pre-Modification Loan Balance		$ 0	$ 0
Restructured loans, Period End Balance		$ 0	$ 0
Financing Receivable, Modifications, Number of Contracts | loans	0
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured loans, Number of Loans | loans		9	8
Restructured loans, Restructured loans, Pre-Modification Loan Balance		$ 3,024,000	$ 3,385,000
Restructured loans, Period End Balance		$ 2,932,000	$ 3,150,000
Financing Receivable, Modifications, Number of Contracts | loans	0
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured loans, Number of Loans | loans		30	13
Restructured loans, Restructured loans, Pre-Modification Loan Balance		$ 3,415,000	$ 1,148,000
Restructured loans, Period End Balance		$ 3,062,000	$ 1,073,000
Financing Receivable, Modifications, Number of Contracts | loans	24
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 1,953,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 1,847,000
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured loans, Number of Loans | loans		14	5
Restructured loans, Restructured loans, Pre-Modification Loan Balance		$ 395,000	$ 95,000
Restructured loans, Period End Balance		$ 366,000	$ 192,000
Financing Receivable, Modifications, Number of Contracts | loans	11
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 351,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 349,000
Installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured loans, Number of Loans | loans		2	0
Restructured loans, Restructured loans, Pre-Modification Loan Balance		$ 41,000	$ 0
Restructured loans, Period End Balance		$ 39,000	$ 0
Financing Receivable, Modifications, Number of Contracts | loans	2
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 35,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 22,000
Installment | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Number of Contracts | entity	53
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	$ 7,700,000
Hotel [Member] | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	$ 186,200,000
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Percent	58.00%
Franchise [Member] | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Amount	$ 44,300,000
Financing Receivable, Non-Troubled Debt Restructuring Modifications, Percent	14.00%

LOANS - Nonaccrual, Restructure

LOANS - Nonaccrual, Restructured and Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	$ 25,919
Financing Receivable, Nonaccrual, No Allowance	54,833
Nonaccrual loans	80,752	$ 48,165	$ 70,700
Restructured loans - accrual status	7,100	11,400	16,100
Total nonpeforming loans		59,600
Interest income effect
Gross amount of interest that would have been recorded under original terms	5,892	5,813	4,656
Interest included in income
Nonaccrual loans	1,636	1,042	715
Restructured loans	426	801	642
Impaired Financing Receivable, Interest Income, Accrual Method	2,062	1,843	1,357
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	3,830	3,970	3,299
Loans and Leases Receivable-Nonaccrual, future commitment to lend	0	3	200
Restructured loans - nonaccrual status	14,700	18,500	22,400
Commercial & industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	18,711
Financing Receivable, Nonaccrual, No Allowance	10,519
Nonaccrual loans	29,230	24,346	30,925
Total nonpeforming loans		27,480
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		1,013	404
Lease financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0
Financing Receivable, Nonaccrual, No Allowance	0
Nonaccrual loans	0	223	22
Total nonpeforming loans		223
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		0	0
Construction real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0
Financing Receivable, Nonaccrual, No Allowance	0
Nonaccrual loans	0	0	9
Total nonpeforming loans		0
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		0	2
Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	6,957
Financing Receivable, Nonaccrual, No Allowance	27,725
Nonaccrual loans	34,682	7,295	20,500
Total nonpeforming loans		10,831
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		388	508
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	251
Financing Receivable, Nonaccrual, No Allowance	11,350
Nonaccrual loans	11,601	10,892	13,495
Total nonpeforming loans		15,162
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		319	324
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0
Financing Receivable, Nonaccrual, No Allowance	5,076
Nonaccrual loans	5,076	5,242	5,580
Total nonpeforming loans		5,700
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		121	117
Installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Nonaccrual, With Allowance	0
Financing Receivable, Nonaccrual, No Allowance	163
Nonaccrual loans	$ 163	167	169
Total nonpeforming loans		204
Interest included in income
Impaired Financing Receivable, Interest Income, Accrual Method		$ 2	$ 2

LOANS - Investment in Impaired

LOANS - Investment in Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Current balance		$ 59,600
Contractual Principal Balance		84,482
Allowance for loan and lease losses		2,175
Average Recorded Investment		79,318	$ 59,728
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		1,713
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		130
Total interest included in income	$ 2,062	1,843	1,357
Commercial & industrial
Financing Receivable, Impaired [Line Items]
Current balance		27,480
Contractual Principal Balance		41,222
Allowance for loan and lease losses		2,044
Average Recorded Investment		36,567	15,398
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		926
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		87	44
Total interest included in income		1,013	404
Lease financing
Financing Receivable, Impaired [Line Items]
Current balance		223
Contractual Principal Balance		223
Allowance for loan and lease losses		0
Average Recorded Investment		225	21
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0	0
Total interest included in income		0	0
Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance		0
Contractual Principal Balance		0
Allowance for loan and lease losses		0
Average Recorded Investment		6	20
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0	0
Total interest included in income		0	2
Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance		10,831
Contractual Principal Balance		18,572
Allowance for loan and lease losses		113
Average Recorded Investment		20,096	26,140
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		357
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		31	18
Total interest included in income		388	508
Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance		15,162
Contractual Principal Balance		17,662
Allowance for loan and lease losses		18
Average Recorded Investment		16,361	12,254
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		307
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		12	23
Total interest included in income		319	324
Home equity
Financing Receivable, Impaired [Line Items]
Current balance		5,700
Contractual Principal Balance		6,462
Allowance for loan and lease losses		0
Average Recorded Investment		5,893	5,621
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		121
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0	3
Total interest included in income		121	117
Installment
Financing Receivable, Impaired [Line Items]
Current balance		204
Contractual Principal Balance		341
Allowance for loan and lease losses		0
Average Recorded Investment		170	274
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method		2
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		0	0
Total interest included in income		2	2
Nonperforming Financing Receivables With Related Allowance [Member]
Financing Receivable, Impaired [Line Items]
Current balance		11,719
Contractual Principal Balance		22,482
Allowance for loan and lease losses		2,175
Average Recorded Investment		6,563	3,277
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method			88
Loans with no related allowance recorded [member]
Financing Receivable, Impaired [Line Items]
Current balance		47,881
Contractual Principal Balance		62,000
Allowance for loan and lease losses		0
Average Recorded Investment		72,755	56,451
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			1,269
Loans with no related allowance recorded [member] | Commercial & industrial
Financing Receivable, Impaired [Line Items]
Current balance		16,726
Contractual Principal Balance		19,709
Allowance for loan and lease losses		0
Average Recorded Investment		31,846	14,498
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			360
Loans with no related allowance recorded [member] | Lease financing
Financing Receivable, Impaired [Line Items]
Current balance		223
Contractual Principal Balance		223
Allowance for loan and lease losses		0
Average Recorded Investment		168	21
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			0
Loans with no related allowance recorded [member] | Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance		0
Contractual Principal Balance		0
Allowance for loan and lease losses		0
Average Recorded Investment		6	20
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			2
Loans with no related allowance recorded [member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance		10,160
Contractual Principal Balance		17,897
Allowance for loan and lease losses		0
Average Recorded Investment		18,757	24,738
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			490
Loans with no related allowance recorded [member] | Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance		14,868
Contractual Principal Balance		17,368
Allowance for loan and lease losses		0
Average Recorded Investment		15,915	11,359
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			301
Loans with no related allowance recorded [member] | Home equity
Financing Receivable, Impaired [Line Items]
Current balance		5,700
Contractual Principal Balance		6,462
Allowance for loan and lease losses		0
Average Recorded Investment		5,893	5,541
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			114
Loans with no related allowance recorded [member] | Installment
Financing Receivable, Impaired [Line Items]
Current balance		204
Contractual Principal Balance		341
Allowance for loan and lease losses		0
Average Recorded Investment		170	274
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method			2
Nonperforming Financing Receivables With Related Allowance [Member] | Commercial & industrial
Financing Receivable, Impaired [Line Items]
Current balance		10,754
Contractual Principal Balance		21,513
Allowance for loan and lease losses		2,044
Average Recorded Investment		4,721	900
Nonperforming Financing Receivables With Related Allowance [Member] | Lease financing
Financing Receivable, Impaired [Line Items]
Current balance		0
Contractual Principal Balance		0
Allowance for loan and lease losses		0
Average Recorded Investment		57	0
Nonperforming Financing Receivables With Related Allowance [Member] | Construction real estate
Financing Receivable, Impaired [Line Items]
Current balance		0
Contractual Principal Balance		0
Allowance for loan and lease losses		0
Average Recorded Investment		0	0
Nonperforming Financing Receivables With Related Allowance [Member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Current balance		671
Contractual Principal Balance		675
Allowance for loan and lease losses		113
Average Recorded Investment		1,339	1,402
Nonperforming Financing Receivables With Related Allowance [Member] | Residential real estate
Financing Receivable, Impaired [Line Items]
Current balance		294
Contractual Principal Balance		294
Allowance for loan and lease losses		18
Average Recorded Investment		446	895
Nonperforming Financing Receivables With Related Allowance [Member] | Home equity
Financing Receivable, Impaired [Line Items]
Current balance		0
Contractual Principal Balance		0
Allowance for loan and lease losses		0
Average Recorded Investment		0	80
Nonperforming Financing Receivables With Related Allowance [Member] | Installment
Financing Receivable, Impaired [Line Items]
Current balance		0
Contractual Principal Balance		0
Allowance for loan and lease losses		0
Average Recorded Investment		$ 0	$ 0

LOANS - Collateral Dependent Lo

LOANS - Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	$ 9,900,970	$ 9,201,665
Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	36,803
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	29,837
Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	3,269
Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	6,444
Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	17,893
Total Collateral
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	99,301
Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	5,055
Commercial & industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	45,456	7,242,074
Commercial & industrial | Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	30,961
Commercial & industrial | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	6,130
Commercial & industrial | Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	2,608
Commercial & industrial | Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	865
Commercial & industrial | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Commercial & industrial | Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	4,892
Commercial real estate-investor
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	27,282
Commercial real estate-investor | Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Commercial real estate-investor | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	20,212
Commercial real estate-investor | Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	661
Commercial real estate-investor | Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	5,537
Commercial real estate-investor | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	872
Commercial real estate-investor | Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Commercial real estate-owner
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	9,723
Commercial real estate-owner | Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	5,842
Commercial real estate-owner | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	3,495
Commercial real estate-owner | Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Commercial real estate-owner | Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	42
Commercial real estate-owner | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	344
Commercial real estate-owner | Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Home Equity Loan
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	5,076
Home Equity Loan | Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Home Equity Loan | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Home Equity Loan | Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Home Equity Loan | Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Home Equity Loan | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	5,076
Home Equity Loan | Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	11,601	1,055,949
Residential real estate | Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Residential real estate | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Residential real estate | Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Residential real estate | Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Residential real estate | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	11,601
Residential real estate | Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Installment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	163	$ 82,589
Installment | Business assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Installment | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Installment | Equipment
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Installment | Land
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Installment | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	0
Installment | Other Property
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans and leases	$ 163

LOANS - Changes in Other Real E

LOANS - Changes in Other Real Estate Owned (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of year	$ 2,033	$ 1,401	$ 2,781
Additions	1,017	2,448	3,182
Proceeds from Sale of Other Real Estate	2,076	1,453	3,797
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Other Deduction	(313)	363	765
Balance at end of year	1,287	2,033	1,401
Commercial & industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Additions	510	415	1,269
Proceeds from Sale of Other Real Estate	217	541	2,967
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Other Deduction	(448)	112	355
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Additions	507	2,033	1,913
Proceeds from Sale of Other Real Estate	1,859	912	830
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Other Deduction	$ 135	$ 251	$ 410

ALLOWANCE FOR CREDIT LOSSES - C

ALLOWANCE FOR CREDIT LOSSES - Changes in the Allowance for Credit Losses for the Previous Three Years (Detail) - USD ($) $ in Thousands	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for loan and lease losses
Balance at beginning of year	$ 57,650	$ 57,650	$ 56,542	$ 54,021
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	61,505	61,505
Provision for loan and lease losses		70,796	30,598	14,586
Loans charged off		(21,359)	(35,565)	(20,670)
Recoveries		7,087	6,075	8,605
Total net charge-offs		14,272	29,490	12,065
Balance at end of year	119,155	175,679	57,650	56,542
Commercial & Industrial
Allowance for loan and lease losses
Balance at beginning of year	18,584	18,584	18,746	17,598
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	9,901	9,901
Provision for loan and lease losses		25,407	23,631	10,615
Loans charged off		(5,345)	26,676	(11,533)
Recoveries		2,907	2,883	2,066
Total net charge-offs		2,438	23,793	9,467
Balance at end of year	28,485	51,454	18,584	18,746
Lease financing
Allowance for loan and lease losses
Balance at beginning of year	971	971	1,130	675
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	118	118
Provision for loan and lease losses		758	3	454
Loans charged off		(852)	162	0
Recoveries		0	0	1
Total net charge-offs		852	162	(1)
Balance at end of year	1,089	995	971	1,130
Construction real estate
Allowance for loan and lease losses
Balance at beginning of year	2,381	2,381	3,413	3,577
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	11,579	11,579
Provision for loan and lease losses		7,759	(1,100)	(310)
Loans charged off		0	0	0
Recoveries		17	68	146
Total net charge-offs		(17)	(68)	(146)
Balance at end of year	13,960	21,736	2,381	3,413
Commercial real estate
Allowance for loan and lease losses
Balance at beginning of year	23,579	23,579	21,048	20,930
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	24,118	24,118
Provision for loan and lease losses		38,936	5,107	847
Loans charged off		(12,100)	3,689	(4,835)
Recoveries		2,262	1,113	4,106
Total net charge-offs		9,838	2,576	729
Balance at end of year	47,697	76,795	23,579	21,048
Residential
Allowance for loan and lease losses
Balance at beginning of year	5,299	5,299	4,964	4,683
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	5,490	5,490
Provision for loan and lease losses		(2,122)	739	492
Loans charged off		(488)	677	(422)
Recoveries		381	273	211
Total net charge-offs		107	404	211
Balance at end of year	10,789	8,560	5,299	4,964
Home equity
Allowance for loan and lease losses
Balance at beginning of year	4,787	4,787	5,348	4,935
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	8,430	8,430
Provision for loan and lease losses		(939)	695	829
Loans charged off		(1,541)	(2,591)	(1,725)
Recoveries		1,132	1,335	1,309
Total net charge-offs		409	1,256	416
Balance at end of year	13,217	11,869	4,787	5,348
Installment
Allowance for loan and lease losses
Balance at beginning of year	392	392	362	307
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	801	801
Provision for loan and lease losses		12	2	(85)
Loans charged off		(148)	(223)	(435)
Recoveries		158	251	575
Total net charge-offs		(10)	(28)	(140)
Balance at end of year	1,193	1,215	392	362
Credit card
Allowance for loan and lease losses
Balance at beginning of year	1,657	1,657	1,531	1,316
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method	1,068	1,068
Provision for loan and lease losses		985	1,521	1,744
Loans charged off		(885)	1,547	(1,720)
Recoveries		230	152	191
Total net charge-offs		655	1,395	1,529
Balance at end of year	$ 2,725	$ 3,055	$ 1,657	$ 1,531

ALLOWANCE FOR CREDIT LOSSES -_2

ALLOWANCE FOR CREDIT LOSSES - Changes in the Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	$ 175,679	$ 119,155	$ 57,650	$ 56,542	$ 54,021
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			2,175
Ending allowance on loans collectively evaluated for impairment			55,475
Impaired Financing Receivable, Related Allowance			57,650
Loans and Leases:
Ending balance of loans individually evaluated for impairment			59,600
Ending balance of loans collectively evaluated for impairment			9,142,065
Loans and Leases Receivable, Net of Deferred Income	9,900,970		9,201,665
Commercial & Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	51,454	28,485	18,584	18,746	17,598
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			2,044
Ending allowance on loans collectively evaluated for impairment			16,540
Impaired Financing Receivable, Related Allowance			18,584
Loans and Leases:
Ending balance of loans individually evaluated for impairment			27,480
Ending balance of loans collectively evaluated for impairment			2,438,397
Loans and Leases Receivable, Net of Deferred Income			2,465,877
Lease financing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	995	1,089	971	1,130	675
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			0
Ending allowance on loans collectively evaluated for impairment			971
Impaired Financing Receivable, Related Allowance			971
Loans and Leases:
Ending balance of loans individually evaluated for impairment			223
Ending balance of loans collectively evaluated for impairment			88,141
Loans and Leases Receivable, Net of Deferred Income			88,364
Construction real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	21,736	13,960	2,381	3,413	3,577
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			0
Ending allowance on loans collectively evaluated for impairment			2,381
Impaired Financing Receivable, Related Allowance			2,381
Loans and Leases:
Ending balance of loans individually evaluated for impairment			0
Ending balance of loans collectively evaluated for impairment			493,182
Loans and Leases Receivable, Net of Deferred Income			493,182
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	76,795	47,697	23,579	21,048	20,930
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			113
Ending allowance on loans collectively evaluated for impairment			23,466
Impaired Financing Receivable, Related Allowance			23,579
Loans and Leases:
Ending balance of loans individually evaluated for impairment			10,831
Ending balance of loans collectively evaluated for impairment			4,183,820
Loans and Leases Receivable, Net of Deferred Income			4,194,651
Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	8,560	10,789	5,299	4,964	4,683
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			18
Ending allowance on loans collectively evaluated for impairment			5,281
Impaired Financing Receivable, Related Allowance			5,299
Loans and Leases:
Ending balance of loans individually evaluated for impairment			15,162
Ending balance of loans collectively evaluated for impairment			1,040,787
Loans and Leases Receivable, Net of Deferred Income	11,601		1,055,949
Home equity
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	11,869	13,217	4,787	5,348	4,935
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			0
Ending allowance on loans collectively evaluated for impairment			4,787
Impaired Financing Receivable, Related Allowance			4,787
Loans and Leases:
Ending balance of loans individually evaluated for impairment			5,700
Ending balance of loans collectively evaluated for impairment			766,169
Loans and Leases Receivable, Net of Deferred Income			771,869
Installment
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	1,215	1,193	392	362	307
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			0
Loans and Leases:
Loans and Leases Receivable, Net of Deferred Income			1,959,591
Installment
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			0
Ending allowance on loans collectively evaluated for impairment			392
Impaired Financing Receivable, Related Allowance			392
Loans and Leases:
Ending balance of loans individually evaluated for impairment			204
Ending balance of loans collectively evaluated for impairment			82,385
Loans and Leases Receivable, Net of Deferred Income	163		82,589
Credit card
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Allowance	$ 3,055	$ 2,725	1,657	$ 1,531	$ 1,316
Allowance for loan and lease losses:
Ending allowance on loans individually evaluated for impairment			0
Ending allowance on loans collectively evaluated for impairment			1,657
Impaired Financing Receivable, Related Allowance			1,657
Loans and Leases:
Ending balance of loans individually evaluated for impairment			0
Ending balance of loans collectively evaluated for impairment			49,184
Loans and Leases Receivable, Net of Deferred Income			$ 49,184

ALLOWANCE FOR CREDIT LOSSES ALL

ALLOWANCE FOR CREDIT LOSSES ALLOWANCE FOR CREDIT LOSSES - Additional information (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Interest Receivable			$ 37,682
Reserves for unfunded commitments			12,500	$ 600
Off-Balance Sheet, Credit Loss, Liability, Change in Method, Credit Loss Expense (Reversal)	$ 12,155		12,200
Provision for Other Credit Losses		$ (200)	$ (237)	$ (165)	$ 273

PREMISES AND EQUIPMENT - Schedu

PREMISES AND EQUIPMENT - Schedule of Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 321,880	$ 328,940
Less accumulated depreciation and amortization	114,669	114,434
Total premises and equipment	207,211	214,506
Operating Leases, Rent Expense	9,100	11,200	$ 9,100
Land and land improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	52,373	54,958
Buildings [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	161,371	163,277
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	70,177	74,881
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	29,525	31,728
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 8,434	$ 4,096

LEASES - Lease Cost (Details)

LEASES - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Cost	$ 7,897	$ 7,324
Short-term Lease, Cost	142	55
Variable Lease, Cost	2,532	2,553
Total operating lease cost	$ 10,571	$ 9,932

LEASES - Lease Maturity (Detail

LEASES - Lease Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Lessee, Operating Lease, Liability, to be Paid, Year One	$ 6,864
Lessee, Operating Lease, Liability, to be Paid, Year Two	7,074
Lessee, Operating Lease, Liability, to be Paid, Year Three	7,143
Lessee, Operating Lease, Liability, to be Paid, Year Four	6,858
Lessee, Operating Lease, Liability, to be Paid, Year Five	6,217
Lessee, Operating Lease, Liability, to be Paid, after Year Five	56,951
Total lease payments	91,107
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	$ 19,395
Operating Lease, Liability	us-gaap:OtherLiabilities	us-gaap:OtherLiabilities

LEASES - Schedule of supplement

LEASES - Schedule of supplemental balance sheet information related to leases (Details)	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	15 years 1 month 6 days	15 years 7 months 6 days
Operating Lease, Weighted Average Discount Rate, Percent	3.07%	3.43%

LEASES - Supplemental cash flow

LEASES - Supplemental cash flow information related to leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating Lease, Payments	$ 8,196	$ 7,335	$ 0
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 9,725	$ 64,902

LEASES - Additional Information

LEASES - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Right-of-Use Asset	$ 63.9	$ 58.6
Operating Lease, Liability	us-gaap:OtherLiabilities	us-gaap:OtherLiabilities
Operating Lease, Liability	us-gaap:OtherLiabilities	us-gaap:OtherLiabilities
Accrued interest and other liabilities
Leases [Abstract]
Operating Lease, Liability	us-gaap:OtherLiabilities
Operating Lease, Liability	us-gaap:OtherLiabilities

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL AND OTHER INTANGIBLE ASSETS-Schedule of Goodwill (Details) - USD ($) $ in Thousands	Aug. 30, 2019	Apr. 01, 2018	Sep. 30, 2019	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance at beginning of year					$ 937,771	$ 880,251	$ 204,084
Goodwill	$ 58,000	$ 675,643	$ 58,000	$ 676,200	0	57,520	676,167
Balance at end of year					$ 937,771	$ 937,771	$ 880,251

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL AND OTHER INTANGIBLE ASSETS-Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 100,564	$ 100,544
Finite-Lived Intangible Assets, Accumulated Amortization	36,012	24,343
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	51,031	51,031
Finite-Lived Intangible Assets, Accumulated Amortization	27,524	21,149
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	39,420	39,420
Finite-Lived Intangible Assets, Accumulated Amortization	4,778	1,195
Other
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	10,113	10,093
Finite-Lived Intangible Assets, Accumulated Amortization	$ 3,710	$ 1,999

GOODWILL AND OTHER INTANGIBLE_5

GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL AND OTHER INTANGIBLE ASSETS-Schedule of Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2020USD ($)
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Finite-Lived Intangible Asset, Expected Amortization, Year One	$ 10,249
Finite-Lived Intangible Asset, Expected Amortization, Year Two	7,708
Finite-Lived Intangible Asset, Expected Amortization, Year Three	6,729
Finite-Lived Intangible Asset, Expected Amortization, Year Four	6,660
Finite-Lived Intangible Asset, Expected Amortization, Year Five	$ 6,611

GOODWILL AND OTHER INTANGIBLE_6

GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL AND OTHER INTANGIBLE ASSETS--Additional Information (Details) - USD ($) $ in Thousands	Aug. 30, 2019	Apr. 01, 2018	Sep. 30, 2019	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 58,000	$ 675,643	$ 58,000	$ 676,200	$ 0	$ 57,520	$ 676,167
Intangible assets amortization					$ 11,126	$ 9,671	$ 7,359
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization method					accelerated basis
Estimated weighted average life (in years)					7 years 1 month 6 days
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization method					straight-line basis
Estimated weighted average life (in years)					11 years
Finite-lived Intangible Assets Acquired	$ 39,400

DEPOSITS (Details)

DEPOSITS (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deposits [Abstract]
Time Deposit Maturities, Year One	$ 1,544,131
Time Deposit Maturities, Year Two	215,855
Time Deposit Maturities, Year Three	56,882
Time Deposit Maturities, Year Four	32,978
Time Deposit Maturities, Year Five	22,210
Time Deposit Maturities, after Year Five	677
Time	$ 1,872,733	$ 2,240,441

DEPOSITS-Additional Information

DEPOSITS-Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deposits [Abstract]
Time Deposits, at or Above FDIC Insurance Limit	$ 220.5	$ 285

BORROWINGS BORROWINGS - Repurch

BORROWINGS BORROWINGS - Repurchase Agreements (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Securities Sold under Agreements to Repurchase	$ 126,594
Carrying Value of Securities Sold under Repurchase Agreements and Deposits Received for Securities Loaned	126,700	$ 90,200
Collateralized Mortgage Obligations
Securities Sold under Agreements to Repurchase	47,359
Mortgage-backed securities
Securities Sold under Agreements to Repurchase	$ 79,235

BORROWINGS - Schedule of Short-

BORROWINGS - Schedule of Short-term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Short-term Debt [Line Items]
Short-term Debt	$ 166,594	$ 1,316,181	$ 1,040,691
Short-term debt interest rate	0.05%	1.62%	2.33%
Short-term debt, average for the year	$ 590,903	$ 1,146,719	$ 947,427
Short-term debt, average rate (as a percent)	1.09%	1.90%	1.90%
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]
Short-term Debt [Line Items]
Short-term Debt	$ 166,594	$ 165,181	$ 183,591
Short-term debt interest rate	0.05%	0.85%	1.65%
Short-term debt, average for the year	$ 149,036	$ 155,859	$ 87,221
Short-term debt, average rate (as a percent)	0.26%	1.15%	0.58%
Short-term debt, maximum month-end balances	$ 260,621	$ 260,621	$ 183,591
Federal Home Loan Bank Borrowings [Member]
Short-term Debt [Line Items]
Short-term Debt	$ 0	$ 1,151,000	$ 857,100
Short-term debt interest rate	0.00%	1.73%	2.48%
Short-term debt, average for the year	$ 441,867	$ 990,860	$ 857,028
Short-term debt, average rate (as a percent)	1.37%	2.37%	2.03%
Short-term debt, maximum month-end balances	$ 1,171,400	$ 1,171,400	$ 1,170,800
Short-term Debt
Short-term Debt [Line Items]
Short-term debt, average for the year	$ 0	$ 0	$ 3,178
Short-term debt, average rate (as a percent)	0.00%	0.00%	4.36%
Short-term debt, maximum month-end balances	$ 0	$ 0	$ 10,000

BORROWINGS - Schedule of Long-t

BORROWINGS - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Amount
FHLB long-term advances	$ 19,971	$ 242,428
Subordinated Debt	321,384	170,967
Unamortized debt issuance costs	(2,770)	(1,007)
Finance Lease, Liability	1,860	1,213
Other Long-term Debt	775	775
Total long-term debt	$ 776,202	$ 414,376
Average Rate
Federal Home Loan Bank	1.43%	1.94%
Debt, Weighted Average Interest Rate	4.86%	4.97%
Lessee, Finance Lease, Discount Rate	3.81%	4.48%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	0.00%	0.00%
Long-term Debt, Weighted Average Interest Rate, at Point in Time	2.25%	3.20%
Maturities of Long-term Debt [Abstract]
2020	$ 20,050
2021	435,065
2022	87
2023	91
2024	96
Thereafter	320,813
Secured Debt	$ 434,982	$ 0
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	0.35%

BORROWINGS Borrowings - - Addit

BORROWINGS Borrowings - - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Subordinated Debt		$ 321,384	$ 170,967
Debt, Weighted Average Interest Rate		4.86%	4.97%
Subordinated debt, original issue		$ 120,000
Subordinated Borrowing, Interest Rate		5.13%
Book value of FHLB collateral		$ 6,300,000
Convertible Subordinated Debt		$ 150,000
Debt Instrument, Basis Spread on Variable Rate		5.09%
Secured Debt		$ 434,982	$ 0
Long Term Debt Percentage in Basis Points		35
Federal Home Loan Bank		1.43%	1.94%
Repayments of Debt, Maturing in More than Three Months		$ 120,000
Private Placement [Member]
Debt Instrument [Line Items]
Subordinated Debt		$ 8,400
Debt, Weighted Average Interest Rate		6.00%
Long-term Debt [Member]
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate		5.25%
Subordinated Debt [Member]
Debt Instrument [Line Items]
Subordinated Debt		$ 49,500
Debt Instrument Maturity Period		30 years
DebtInstrumentMinimumCallablePeriod		5 years
Private Placement [Member]
Debt Instrument [Line Items]
DebtInstrumentMinimumCallablePeriod	5 years

DERIVATIVES - Additional Inform

DERIVATIVES - Additional Information (Detail) $ in Thousands	Dec. 31, 2020USD ($)entity	Dec. 31, 2019USD ($)entity
Derivative [Line Items]
Number of counterparties | entity	20	18
Derivative Asset	$ 272,499	$ 112,607
Derivative Assets (Liabilities), at Fair Value, Net	(107)
Derivative Liability	272,606	112,616
Derivative, Notional Amount	$ 11,875,690	$ 7,586,618
Foreign Exchange [Member]
Derivative [Line Items]
Number of counterparties | entity	6	6
Credit Risk Contract [Member]
Derivative [Line Items]
Outstanding liability from counterparty contracts	$ 300	$ 200
Derivative, Notional Amount	242,400	216,200
Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Derivative, Notional Amount	114,200	33,400
Other Credit Derivatives [Member]
Derivative [Line Items]
Outstanding liability from counterparty contracts		900
Derivative, Notional Amount	112,600	37,800
Credit Risk Derivative Assets, at Fair Value	2,700
Derivative [Member] | Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability	182,300	67,500
Derivative, Notional Amount	2,300,000	1,900,000
Derivative [Member] | Other Liabilities [Member] | Foreign Exchange [Member]
Derivative [Line Items]
Derivative Liability	33,100	18,300
Derivative, Notional Amount	$ 3,600,000	$ 1,900,000

DERIVATIVES - Summary of Deriva

DERIVATIVES - Summary of Derivative Financial Instruments and Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 11,875,690	$ 7,586,618
Derivative Asset	272,499	112,607
Estimate Fair Value Loss	(272,606)	(112,616)
Fair Value Hedges | Matched interest rate swaps | Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,300,336	1,923,375
Derivative Asset	107	2,636
Estimate Fair Value Loss	(184,884)	(70,808)
Fair Value Hedges | Matched interest rate swaps | Accrued interest and other assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,300,336	1,923,375
Derivative Asset	184,777	70,799
Estimate Fair Value Loss	(107)	(2,636)
Foreign Exchange [Member] | Matched interest rate swaps | Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,637,509	1,869,934
Derivative Asset	27,249	10,433
Estimate Fair Value Loss	(60,366)	(28,739)
Foreign Exchange [Member] | Matched interest rate swaps | Accrued interest and other assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,637,509	1,869,934
Derivative Asset	60,366	28,739
Estimate Fair Value Loss	(27,249)	(10,433)
Derivative [Member] | Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	2,300,000	1,900,000
Estimate Fair Value Loss	$ (182,300)	$ (67,500)

DERIVATIVES - Disclosure by Typ

DERIVATIVES - Disclosure by Type of Financial Instrument (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 272,606	$ 112,616
Derivative Liability, Fair Value, Gross Asset	(402,480)	(188,395)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		(75,779)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(129,874)
Fair Value Hedges | Matched interest rate swaps | Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	184,991	73,444
Derivative Liability, Fair Value, Gross Asset	(385,088)	(147,193)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		73,749
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(200,097)
Fair Value Hedges | Foreign Exchange [Member] | Accrued interest and other liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	87,615	39,172
Derivative Liability, Fair Value, Gross Asset	(17,392)	(41,202)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$ 70,223	$ (2,030)

DERIVATIVES - Derivative Financ

DERIVATIVES - Derivative Financial Instruments, Average Remaining Maturity and the Weighted-Average Interest Rates being Paid and Received (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative, Notional Amount	$ 11,875,690	$ 7,586,618
Average Maturity (years)	2 years 3 months 18 days
Fair Value	$ (107)
Asset conversion swaps | Derivative Financial Instruments Receive Fixed Pay Variable
Derivative [Line Items]
Derivative, Notional Amount	$ 2,300,336
Average Maturity (years)	4 years 10 months 24 days
Fair Value	$ 184,670
Asset conversion swaps | Derivative Financial Instruments Receive Variable Pay Fixed
Derivative [Line Items]
Derivative, Notional Amount	$ 2,300,336
Average Maturity (years)	4 years 10 months 24 days
Fair Value	$ (184,777)
Foreign Exchange [Member] | Derivative Financial Instruments Receive Fixed Pay Variable
Derivative [Line Items]
Derivative, Notional Amount	$ 3,637,509
Average Maturity (years)	7 months 6 days
Fair Value	$ 33,117
Foreign Exchange [Member] | Derivative Financial Instruments Receive Variable Pay Fixed
Derivative [Line Items]
Derivative, Notional Amount	$ 3,637,509
Average Maturity (years)	7 months 6 days
Fair Value	$ (33,117)

RELATED PARTIES TRANSACTIONS (D

RELATED PARTIES TRANSACTIONS (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Loans to Related Parties [Roll Forward]
Beginning balance	$ 5,289
Additions	1,811
Deductions	(2,003)
Ending balance	5,097
Loans 90 days past due	$ 0

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	$ 9,900,970	$ 9,201,665
Unused Commitments to Extend Credit	2,853,059
Commercial & industrial
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,007,509	2,465,877
Unused Commitments to Extend Credit	1,270,765
Lease financing
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	72,987	88,364
Unused Commitments to Extend Credit	0
Construction real estate
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	636,096	493,182
Unused Commitments to Extend Credit	374,008
Commercial real estate
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	4,307,858	4,194,651
Commercial real estate-investor
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	3,244,540
Unused Commitments to Extend Credit	139,754
Commercial real estate-owner
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	1,063,318
Unused Commitments to Extend Credit	51,637
Residential real estate
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	1,003,086	1,055,949
Unused Commitments to Extend Credit	28,895
Home equity
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	743,099	771,869
Unused Commitments to Extend Credit	762,406
Installment
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	81,850	82,589
Unused Commitments to Extend Credit	18,229
Credit card
Other Commitments [Line Items]
Loans and Leases Receivable, Net of Deferred Income	48,485	$ 49,184
Unused Commitments to Extend Credit	$ 207,365

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2020
Commitments and Contingencies Disclosure [Line Items]
Reserves for unfunded commitments	$ 12,500	$ 600
Loans and Leases Receivable, Commitments, Fixed Rates	123,600	123,700
Loans and Leases Receivable, Commitments, Variable Rates	$ 3,300,000	$ 3,200,000
Loan Commitments, Fixed Interest Rate Range, Minimum	0.00%	0.00%
Loan Commitments, Fixed Interest Rate Range, Maximum	21.00%	21.00%
Loan Commitments, Fixed Rate, Maturities, Minimum	1 year	1 year
Loan Commitments, Fixed Rate, Maturities, Maximum	30 years 9 months 18 days	31 years 7 months 6 days
Letters of credit issued to guarantee performance of a client to a third party	$ 36,100	$ 33,400
Affordable Housing Program Obligation	47,500	38,500
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	13,064	10,075	$ 5,439
Amortization Method Qualified Affordable Housing Project Investments, Amortization	8,100	6,900	5,700
Affordable housing contingent commitment	0	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	4,000	5,100
Estimated Litigation Liability				$ 0
Renewable Energy Recorded Investment	5,200
Renewable Energy Maximimum Exposure to Loss	7,700
Variable Interest Entity, Not Primary Beneficiary [Member]
Commitments and Contingencies Disclosure [Line Items]
Historic Tax Credit Recorded Investment	3,600	3,100
Commitments to Extend Credit
Commitments and Contingencies Disclosure [Line Items]
Commitments outstanding to extend credit	3,400,000	3,300,000
Affordable housing investment [Member]
Commitments and Contingencies Disclosure [Line Items]
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	7,600	6,200	4,900
Historic tax credit [Member]
Commitments and Contingencies Disclosure [Line Items]
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	600	$ 3,500	$ 500
FFBC_RenewableEnergyProgramMember [Member]
Commitments and Contingencies Disclosure [Line Items]
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	$ 4,800

INCOME TAXES (Detail)

INCOME TAXES (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current expense [Abstract]
Federal	$ 34,632	$ 31,343	$ 34,330
State	2,349	854	1,029
Total current expense	36,981	32,197	35,359
Deferred (benefit) expense [Abstract]
Federal	(8,624)	10,946	4,675
State	244	1,644	1,592
Total deferred (benefit) expense	(8,380)	12,590	6,267
Income tax expense	28,601	44,787	41,626
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income taxes computed at federal statutory rate (21%) on income before income taxes	38,726	51,001	44,986
Benefit from tax-exempt income	(5,901)	(5,964)	(4,499)
Tax credits	(13,064)	(10,075)	(5,439)
Basis reduction on tax credit	657	738	0
Tax benefit of equity compensation	340	(140)	(565)
State income taxes, net of federal tax benefit	2,049	1,973	2,070
Affordable housing investments	6,635	5,825	4,725
Other	(841)	1,429	348
Income tax expense	28,601	44,787	41,626
Deferred tax assets [Abstract]
Allowance for credit losses	39,671	13,011
Fair value adjustments on business combinations	3,870	6,470
Deferred compensation	235	228
Postretirement benefits other than pension liability	684	666
Accrued stock-based compensation	1,654	1,296
Other real estate owned write-downs	8	162
Interest on nonaccrual loans	1,712	548
Accrued expenses	5,647	4,708
State net operating loss	1,959	2,792
Deferred tax asset, Leasing liability	16,947	14,806
Federal tax credit carryforwards	2,854	133
Deferred Tax Assets, Deferred Income	1,691	0
Other	577	683
Total deferred tax assets	77,509	45,503
Deferred tax liabilities [Abstract]
Tax depreciation greater than book depreciation	(11,923)	(10,970)
FHLB and FRB stock	(4,043)	(4,043)
Mortgage-servicing rights	(2,925)	(2,435)
Leasing activities	(6,661)	(7,349)
Retirement obligations	10,984	8,511
Intangible assets	(13,942)	(11,647)
Deferred loan fees and costs	0	(1,100)
Prepaid expenses	(619)	(623)
Limited partnership investments	2,471	2,249
Unrealized gains on investment securities	(20,253)	(11,359)
Foreign exchange deferred income	(2,080)	(2,845)
Deferred Tax Liability, Unrealized gain/loss equity securities	(2,179)	(128)
Deferred tax liability, right of use asset	(15,053)	(13,354)
Other	(2,035)	(1,920)
Deferred Tax Liabilities, Gross	(95,168)	(78,533)
Total deferred tax liabilities	(17,659)	(33,030)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Balance at beginning of year	3,006	3,735
Decrease resulting from settlements	(620)	(729)
Balance at end of year	$ 2,386	$ 3,006	$ 3,735
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
Deferred Tax Assets Operating Loss Carryforwards State And Local Acquired	$ 2,500	$ 3,600
Deferred taxes, business combination, valuation allowance	0	0
Retained Earnings For Which No Deferred Income Tax Liability Has Been Recognized	16,100	16,100
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Bad Debt Reserve for Tax Purposes of Qualified Lender	3,400
Unrecognized tax benefits affecting income tax rate	1,900	2,400
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$ 0	$ 0

EMPLOYEE BENEFIT PLANS (Details

EMPLOYEE BENEFIT PLANS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Pension Cost (Reversal of Cost)	$ 2,484,000	$ 1,041,000	$ 859,000
Payment for Pension Benefits	$ 0	0	0
Defined Contribution Plan, Maximum Annual Contribution Percent by Employee	50.00%
Defined Contribution Plan, Cost	$ 0	0	0
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year	0
Change in Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	0.0078
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	75,044,000	68,286,000
Service cost	7,932,000	6,591,000	6,501,000
Interest cost	2,455,000	2,778,000	2,394,000
Actuarial gain (loss)	9,171,000	6,848,000
Defined Benefit Plan, Benefit Obligation, Benefits Paid	7,108,000	9,459,000
Benefit obligation at end of year	87,494,000	75,044,000	68,286,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	141,816,000	130,078,000
Actual return on plan assets	20,996,000	21,197,000
Defined Benefit Plan, Plan Assets, Benefits Paid	7,108,000	9,459,000
Fair value of plan assets at end of year	155,704,000	141,816,000	130,078,000
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Assets	68,210,000	66,772,000
Liabilities	0	0
Net amount recognized	68,210,000	66,772,000
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Abstract]
Net actuarial loss	32,943,000	37,278,000
Net prior service cost	(682,000)	(1,095,000)
Deferred tax assets	(7,349,000)	(8,242,000)
Net amount recognized	24,912,000	27,941,000	32,590,000	$ 19,631,000
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	(3,029,000)	(4,649,000)	8,180,000
Accumulated benefit obligation	86,327,000	74,424,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	7,932,000	6,591,000	6,501,000
Interest cost	2,455,000	2,778,000	2,394,000
Expected return on plan assets	(9,824,000)	(9,718,000)	(9,811,000)
Amortization of prior service cost	(413,000)	(413,000)	(413,000)
Defined Benefit Plan, Amortization of Gain (Loss)	2,334,000	1,803,000	2,188,000
Net periodic benefit (income) cost	2,484,000	1,041,000	859,000
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract]
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Gain (Loss), before Tax	(2,001,000)	(4,630,000)	12,319,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax	0	0	0
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Prior Service Cost, before Tax	413,000	413,000	413,000
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax	(2,334,000)	(1,803,000)	(2,188,000)
Total recognized in accumulated other comprehensive income	(3,922,000)	(6,020,000)	10,544,000
Total recognized in net periodic benefit cost and accumulated other comprehensive income	$ (1,438,000)	$ (4,979,000)	$ 11,403,000
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.55%	3.33%	4.31%
Rate of compensation increase	3.50%	3.50%	3.50%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Weighted-Average Interest Crediting Rate	2.14%	2.82%	3.61%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	3.33%	4.31%	3.43%
Expected return on plan assets	7.25%	7.25%	7.25%
Rate of compensation increase	3.50%	3.50%	3.50%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Weighted-Average Interest Crediting Rate	2.82%	3.61%	2.63%
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2021	$ 5,780,000
2022	5,432,000
2023	5,474,000
2024	6,605,000
2025	6,565,000
Thereafter	$ 38,095,000

EMPLOYEE BENEFIT PLANS Defined

EMPLOYEE BENEFIT PLANS Defined Benefit Plan, Fair Value on Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	$ 155,704	$ 141,816	$ 130,078
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	151,511	136,459
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	4,193	5,357
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	155,704	141,816
Cash | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	129	195
Cash | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Cash | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Cash | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	129	195
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	4,193	5,357
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	4,193	5,357
Fixed income mutual funds | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	65,443	75,720
Fixed income mutual funds | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Fixed income mutual funds | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Fixed income mutual funds | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	65,443	75,720
Equity mutual funds | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	85,939	60,544
Equity mutual funds | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Equity mutual funds | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	0	0
Equity mutual funds | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fair value measurements	$ 85,939	$ 60,544

REVENUE RECOGNITION REVENUE R_2

REVENUE RECOGNITION REVENUE RECOGNITION (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue Recognition and Deferred Revenue [Abstract]
Interchange income	$ 23.9	$ 30.4	$ 31.3
Credit card expense	$ 12.2	$ 11.9	$ 11

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Comprehensive Income (Loss), before Reclassification Adjustments and Tax [Abstract]
Unrealized gain (loss) on debt securities	$ 36,643	$ 65,858	$ (14,461)
Unrealized gain (loss) on derivatives	0	281	628
Retirement obligations	2,001	4,630	(12,319)
Total	38,644	70,769	(26,152)
Other Comprehensive Income (Loss) Reclassifications before Tax [Abstract]
Unrealized gain (loss) on debt securities	(4,563)	(370)	(161)
Unrealized gain (loss) on derivatives	0	0	0
Retirement obligation	1,921	1,390	1,775
Total	(6,484)	(1,760)	(1,936)
Transactions Pre-tax
Unrealized gain (loss) on debt securities	41,206	66,228	(14,300)
Unrealized gain (loss) on derivatives	0	281	628
Retirement obligation	3,922	6,020	(10,544)
Total	45,128	72,529	(24,216)
Transactions Tax-effect
Unrealized gain (loss) on debt securities	(8,894)	(14,269)	3,071
Unrealized gain (loss) on derivatives	0	(64)	(144)
Retirement obligation	(893)	(1,371)	2,364
Total	(9,787)	(15,704)	5,291
Transactions Net of tax
Unrealized gain (loss) on debt securities	32,312	51,959	(11,229)
Unrealized gain (loss) on derivatives	0	217	484
Retirement obligation	3,029	4,649	(8,180)
Total	35,341	56,825	(18,925)
Cumulative effect of accounting change
Unrealized gain (loss) on debt securities		906	(190)
Unrealized gain (loss) on derivatives		0	(124)
Retirement obligation		0	(4,779)
Total		906	(5,093)
Balances Net of tax
Unrealized gain (loss) on debt securities	73,576	41,264	(11,601)	$ (182)
Unrealized gain (loss) on derivatives	0	0	(217)	(577)
Retirement obligation	(24,912)	(27,941)	(32,590)	(19,631)
Total	$ 48,664	$ 13,323	$ (44,408)	$ (20,390)

ACCUMULATED OTHER COMPREHENSI_4

ACCUMULATED OTHER COMPREHENSIVE INCOME AMOUNT RECLASSIFIED FROM ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Realized gains and losses on securities available for sale	$ (4,563)	$ (370)	$ (161)
Amortization of prior service cost	413	413	413
Recognized net actuarial loss	(2,334)	(1,803)	(2,188)
Other Comprehensive Income, Reclassification, Amortization of Defined Benefit Plans items, Pre-tax	(1,921)	(1,390)	(1,775)
Total reclassifications for the period, before tax	$ (6,484)	$ (1,760)	$ (1,936)

CAPITAL - Risk-Based Capital (D

CAPITAL - Risk-Based Capital (Details) $ in Thousands	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Conservation Buffer-Fully Phased-In	2.50%
Banking Regulation, Total Risk-Based Capital, Excess, Actual	$ 566,800
Banking Regulation, Risk-Based Information [Abstract]
Banking Regulation, Common Equity Tier One Risk-Based Capital, Actual	$ 1,325,922	$ 1,245,746
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual	0.1182	0.1130
Banking Regulation, Common Equity Tier One Risk-Based Capital, Capital Adequacy, Minimum	$ 785,338	$ 771,666
Common Equity Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets	0.0700	0.0700
Banking Regulation, Tier One Risk-Based Capital [Abstract]
Banking Regulation, Tier One Risk-Based Capital, Actual	$ 1,368,818	$ 1,288,185
Banking Regulation, Tier One Risk-Based Capital Ratio, Actual	0.1220	0.1169
Banking Regulation, Tier One Risk-Based Capital, Capital Adequacy, Minimum	$ 953,625	$ 937,023
Banking Regulation, Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.085	0.0850
Banking Regulation, Total Capital [Abstract]
Banking Regulation, Total Capital, Actual	$ 1,744,802	$ 1,475,813
Banking Regulation, Total Risk-Based Capital Ratio, Actual	0.1555	0.1339
Banking Regulation, Total Risk-Based Capital, Capital Adequacy, Minimum	$ 1,178,007	$ 1,157,498
Banking Regulation, Total Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.1050	0.1050
Banking Regulation, Tier One Leverage Capital [Abstract]
Banking Regulation, Tier One Leverage Capital, Actual	$ 1,368,818	$ 1,288,185
Banking Regulation, Tier One Leverage Capital Ratio, Actual	0.0955	0.0958
Banking Regulation, Tier One Leverage Capital, Capital Adequacy, Minimum	$ 573,526	$ 537,606
Banking Regulation, Tier One Leverage Capital Ratio, Capital Adequacy, Minimum	0.0400	0.0400
Subsidiaries [Member]
Banking Regulation, Risk-Based Information [Abstract]
Banking Regulation, Common Equity Tier One Risk-Based Capital, Actual	$ 1,452,403	$ 1,333,978
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual	0.1295	0.1211
Banking Regulation, Common Equity Tier One Risk-Based Capital, Capital Adequacy, Minimum	$ 784,807	$ 770,997
Common Equity Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets	0.0700	0.0700
Common Equity Tier One Risk Based Capital Required to be Well Capitalized To Risk Weighted Assets	$ 728,749	$ 715,926
Common Equity Tier One Risk Based Capital Required to be Well Capitalized To Risk Weighted Assets	6.50%	6.50%
Banking Regulation, Tier One Risk-Based Capital [Abstract]
Banking Regulation, Tier One Risk-Based Capital, Actual	$ 1,452,507	$ 1,334,082
Banking Regulation, Tier One Risk-Based Capital Ratio, Actual	0.1296	0.1211
Banking Regulation, Tier One Risk-Based Capital, Capital Adequacy, Minimum	$ 952,980	$ 936,211
Banking Regulation, Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.0850	0.0850
Capital Required for Capital Adequacy to Risk Weighted Assets	$ 896,922	$ 881,140
Banking Regulation, Tier One Risk-Based Capital Ratio, Well Capitalized, Minimum	0.0800	0.0800
Banking Regulation, Total Capital [Abstract]
Banking Regulation, Total Capital, Actual	$ 1,560,457	$ 1,399,817
Banking Regulation, Total Risk-Based Capital Ratio, Actual	0.1392	0.1271
Banking Regulation, Total Risk-Based Capital, Capital Adequacy, Minimum	$ 1,177,211	$ 1,156,496
Banking Regulation, Total Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.1050	0.1050
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	$ 1,121,153	$ 1,101,425
Banking Regulation, Total Risk-Based Capital Ratio, Well Capitalized, Minimum	0.1000	0.1000
Banking Regulation, Tier One Leverage Capital [Abstract]
Banking Regulation, Tier One Leverage Capital, Actual	$ 1,452,507	$ 1,334,082
Banking Regulation, Tier One Leverage Capital Ratio, Actual	0.1014	0.0993
Banking Regulation, Tier One Leverage Capital, Capital Adequacy, Minimum	$ 573,094	$ 537,299
Banking Regulation, Tier One Leverage Capital Ratio, Capital Adequacy, Minimum	0.0400	0.0400
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	$ 716,367	$ 671,623
Banking Regulation, Tier One Leverage Capital Ratio, Well Capitalized, Minimum	0.0500	0.0500

CAPITAL - Share Repurchase (Det

CAPITAL - Share Repurchase (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 22, 2019
Banking Regulation, Total Capital [Abstract]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased				5,000,000
Treasury Stock, Shares, Acquired	880,000	2,753,272	0
Treasury Stock Acquired, Average Cost Per Share	$ 18.96	$ 24.05
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	1,366,728

STOCK OPTIONS AND AWARDS (Detai

STOCK OPTIONS AND AWARDS (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Noncash Expense		$ 7,678	$ 7,969	$ 6,219
Total unrecognized compensation cost					$ 9,100
Unrecognized compensation cost, period for recognition (in years)		1 year 11 months 1 day
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized		4,311,365
Share-based Compensation Arrangement by Share-based Payment Award, Other Share Increase (Decrease)	83,551
Share-based Compensation Arrangement by Share-based Payment Award, Option Term		10 years
Options outstanding at end of year	37,856	37,856	37,856		27,451
Activity for stock option plan [Roll Forward]
Outstanding at beginning of year (in shares)	37,856	37,856
Granted (in shares)		0	0	0
Exercised (in shares)		(10,405)
Forfeited or expired (in shares)		0
Outstanding at end of year (in shares)		27,451	37,856
Exercised (in shares)					27,451
Weighted average exercise price, outstanding at beginning of year (in dollars per share)	$ 9.54	$ 9.54
Weighted average exercise price, granted (in dollars per share)		0
Weighted average exercise price, exercised (in dollars per share)		6.92
Weighted average exercise price, forfeited or expired (in dollars per share)		0
Weighted average exercise price, outstanding at end of year (in dollars per share)		$ 10.53	$ 9.54
Weighted average exercise price, Exercisable (in dollars per share)					$ 10.53
Weighted average remaining contractual term, outstanding at end of year (in years)		2 years 6 months 10 days
Weighted average remaining contractual life, exercisable at end of year (in years)		2 years 6 months 10 days
Aggregate intrinsic value, outstanding at end of year					$ 192
Aggregate intrinsic value, exercisable at end of year					$ 192
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Total intrinsic value of options exercised		$ 86	$ 462	$ 734
Proceeds from exercise of stock options		72	90	284
Share-based Payment Arrangement, Exercise of Option, Tax Benefit		1,776	1,844	1,439
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in period, total fair value		$ 6,100	$ 7,400	$ 5,600
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Number of shares nonvested at beginning of year	530,569	530,569	462,446	468,372
Number of shares granted		503,311	395,023	303,930
Number of shares vested		(233,828)	(295,633)	(267,031)
Number of shares forfeited		(36,769)	(31,267)	(42,825)
Number of shares nonvested at end of year		763,283	530,569	462,446
Weighted average of shares fair value, nonvested at beginning of year	$ 27.19	$ 27.19	$ 26.39	$ 21.63
Weighted average of shares fair value granted		18.62	26.55	28.94
Weighted average of shares fair value vested		26.07	24.94	20.94
Weighted average of shares fair value forfeited		23.79	28.63	26.38
Weighted average of shares fair value, nonvested at end of year		$ 22.04	$ 27.19	$ 26.39

EARNINGS PER COMMON SHARE - Com

EARNINGS PER COMMON SHARE - Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator for basic and diluted earnings per share -income available to common shareholders:
Net income	$ 155,810	$ 198,075	$ 172,595
Denominator for basic earnings per share - weighted average shares	97,363,952	98,305,570	88,582,090
Effect of dilutive securities -
Employee stock awards	729,146	545,901	514,680
Warrants	0	0	517,435
Denominator for diluted earnings per share - adjusted weighted average shares	98,093,098	98,851,471	89,614,205
Basic	$ 1.60	$ 2.01	$ 1.95
Diluted	$ 1.59	$ 2	$ 1.93

EARNINGS PER COMMON SHARE - Add

EARNINGS PER COMMON SHARE - Additional Information (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share Disclosure [Line Items]
Preferred Stock, Shares Authorized	10,000,000	10,000,000	10,000,000
Preferred Stock, Shares Outstanding	0	0	0
Antidilutive Stock Options
Earnings Per Share Disclosure [Line Items]
Stock options and warrants with an exercise price greater than the average market price of the common shares not included in the computation of net income per diluted share	0	0	0
Antidilutive Warrants
Earnings Per Share Disclosure [Line Items]
Stock options and warrants with an exercise price greater than the average market price of the common shares not included in the computation of net income per diluted share	0	0
MainSource [Member]
Earnings Per Share Disclosure [Line Items]
Warrants Exercise Price			$ 10.62
MainSource [Member] | Antidilutive Warrants
Earnings Per Share Disclosure [Line Items]
Stock options and warrants with an exercise price greater than the average market price of the common shares not included in the computation of net income per diluted share			804,858

FAIR VALUE DISCLOSURES - Estima

FAIR VALUE DISCLOSURES - Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial assets
Investment securities held-to-maturity	$ 131,687	$ 142,862
Other investments	133,198	125,020
Loans held for sale	41,100	13,700
Interest Receivable	37,682
Deposits
Noninterest-bearing	3,763,709	2,643,928
Savings	3,680,774	2,960,979
Time	1,872,733	2,240,441
Deposits	12,232,003	10,210,229
Carrying value
Financial assets
Cash and short-term investments	251,359	257,639
Investment securities held-to-maturity	131,687	142,862
Other investments	133,198	125,020
Loans and leases	9,725,291	9,144,015
Interest Receivable	50,903	39,591
Deposits
Deposits	12,232,003	10,210,229
Short-term borrowings	166,594	1,316,181
Long-term debt	776,202	414,376
Interest Payable	6,240	13,671
Fair value
Financial assets
Cash and short-term investments	251,359	257,639
Investment securities held-to-maturity	136,698	142,821
Other investments	133,198	125,020
Loans and leases	9,743,497	9,134,215
Interest Receivable	50,903	39,591
Deposits
Deposits	12,238,058	10,209,790
Short-term borrowings	166,594	1,316,181
Long-term debt	774,674	414,937
Interest Payable	6,240	13,671
Fair Value, Inputs, Level 1 [Member] | Fair value
Financial assets
Cash and short-term investments	251,359	257,639
Investment securities held-to-maturity	0	0
Other investments	837	699
Loans and leases	0	0
Interest Receivable	0	0
Deposits
Deposits	0	0
Short-term borrowings	166,594	1,316,181
Long-term debt	0	0
Interest Payable	14	1,899
Fair Value, Inputs, Level 2 [Member] | Fair value
Financial assets
Cash and short-term investments	0	0
Investment securities held-to-maturity	136,698	142,821
Other investments	122,953	123,821
Loans and leases	0	0
Interest Receivable	13,221	12,743
Deposits
Deposits	12,238,058	10,209,790
Short-term borrowings	0	0
Long-term debt	774,674	414,937
Interest Payable	6,226	11,772
Fair Value, Inputs, Level 3 [Member] | Fair value
Financial assets
Cash and short-term investments	0	0
Investment securities held-to-maturity	0	0
Other investments	9,408	500
Loans and leases	9,743,497	9,134,215
Interest Receivable		26,848
Deposits
Deposits	0	0
Short-term borrowings	0	0
Long-term debt	0	0
Interest Payable	$ 0	$ 0

FAIR VALUE DISCLOSURES - Summar

FAIR VALUE DISCLOSURES - Summary of Financial Assets and Liabilities Measure at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Investment securities	$ 3,424,580	$ 2,852,084
Loans Held-for-sale, Fair Value Disclosure	41,100	13,700
Derivatives	272,499	112,607
Liabilities
Derivatives	272,606	112,616
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 [Member] | Fair value
Assets
Loans Held-for-sale, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 [Member]
Assets
Investment securities	103	100
Derivatives		0
Total	103	100
Liabilities
Total	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 [Member] | Fair value
Assets
Loans Held-for-sale, Fair Value Disclosure	41,103	13,680
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 [Member]
Assets
Investment securities	3,383,902	2,842,794
Derivatives		73,558
Total	3,697,652	2,969,204
Liabilities
Total	273,739	112,922
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member] | Fair value
Assets
Loans Held-for-sale, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Assets
Investment securities	40,575	9,190
Derivatives		0
Total	40,575	9,190
Liabilities
Total	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Assets
Investment securities	3,424,580	2,852,084
Loans Held-for-sale, Fair Value Disclosure	41,103	13,680
Derivatives		73,558
Total	3,738,330	2,978,494
Liabilities
Total	273,739	112,922
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 [Member]
Assets
Derivatives	0
Liabilities
Derivatives	0	0
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 [Member]
Assets
Derivatives	185,032
Liabilities
Derivatives	186,124	73,750
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Assets
Derivatives	0
Liabilities
Derivatives	0	0
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Assets
Derivatives	185,032
Liabilities
Derivatives	186,124	73,750
Foreign Exchange [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 [Member]
Assets
Derivatives	0	0
Liabilities
Derivatives	0	0
Foreign Exchange [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 [Member]
Assets
Derivatives	87,615	39,172
Liabilities
Derivatives	87,615	39,172
Foreign Exchange [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Assets
Derivatives	0	0
Liabilities
Derivatives	0	0
Foreign Exchange [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Assets
Derivatives	87,615	39,172
Liabilities
Derivatives	$ 87,615	$ 39,172

FAIR VALUE DISCLOSURES - Reconc

FAIR VALUE DISCLOSURES - Reconciliation of Gains and Losses on Level 3 Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Beginning balance	$ 9,190	$ 14,715
Accretion (amortization)	1	(552)
Increase (decrease) fair value	(17)	30
Settlements	31,401	(5,003)
Ending balance	$ 40,575	$ 9,190

FAIR VALUE DISCLOSURES - Summ_2

FAIR VALUE DISCLOSURES - Summary of Financial Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis (Detail) - Fair Value, Measurements, Nonrecurring - Fair value - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Inputs, Level 1 [Member] | Real Estate Acquired in Satisfaction of Debt
Assets
Total	$ 0	$ 0
Fair Value, Inputs, Level 1 [Member] | Commercial & industrial
Assets
Total	0	0
Fair Value, Inputs, Level 1 [Member] | Commercial real estate
Assets
Total	0	0
Fair Value, Inputs, Level 2 [Member] | Real Estate Acquired in Satisfaction of Debt
Assets
Total	0	0
Fair Value, Inputs, Level 2 [Member] | Commercial & industrial
Assets
Total	0	0
Fair Value, Inputs, Level 2 [Member] | Commercial real estate
Assets
Total	0	0
Fair Value, Inputs, Level 3 [Member] | Real Estate Acquired in Satisfaction of Debt
Assets
Total	54	1,088
Fair Value, Inputs, Level 3 [Member] | Commercial & industrial
Assets
Total	25,367	8,710
Fair Value, Inputs, Level 3 [Member] | Commercial real estate
Assets
Total	$ 6,432	$ 558

FAIR VALUE DISCLOSURES (Details

FAIR VALUE DISCLOSURES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Loans Held-for-sale, Fair Value Disclosure	$ 41.1	$ 13.7
Financing Receivable, Held-for-Sale	35.5	12.7
Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables	5.6	$ 0.9
Fair Value, Option, Changes in Fair Value, Gain (Loss)	$ 4.6

BUSINESS COMBINATIONS - Additio

BUSINESS COMBINATIONS - Additional Information - Narrative (Details) - USD ($) $ in Thousands	Aug. 30, 2019	Apr. 01, 2018	Sep. 30, 2019	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 1,059,504
Cash consideration	$ 53,700	43
Stock consideration	60,900	1,043,424
Total assets acquired	74,900	4,402,804
Total liabilities assumed	18,400	4,018,943			$ 0	$ 18,380	$ 4,018,948
Goodwill	58,000	675,643	$ 58,000	$ 676,200	$ 0	$ 57,520	$ 676,167
Loans		2,792,572
Business Combination, Acquired Receivables, Gross Contractual Amount		$ 2,900,000
Bannockburn [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred	$ 114,600

BUSINESS COMBINATION BUSINESS C

BUSINESS COMBINATION BUSINESS COMBINATIONS (Details) - USD ($) $ in Thousands	Aug. 30, 2019	Apr. 01, 2018	Sep. 30, 2019	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Cash consideration	$ 53,700	$ 43
Stock consideration	60,900	1,043,424
Warrant consideration		14,460
Options consideration		1,577
Total purchase consideration		1,059,504
Cash		71,806
Investment securities available-for-sale		900,935
Investment securities held-to-maturity		171,423
Other investments		28,763
Loans		2,792,572
Premises and equipment		98,814
Intangible assets		42,887
Other assets		167,829
Assets held for sale		127,775
Total assets acquired	74,900	4,402,804
Deposits		3,263,920
Subordinated notes		49,027
FHLB advances		291,887
Other borrowings		205,620
Other liabilities		32,649
Liabilities held for sale		175,840
Total liabilities assumed	18,400	4,018,943			$ 0	$ 18,380	$ 4,018,948
Net identifiable assets		383,861
Goodwill	$ 58,000	$ 675,643	$ 58,000	$ 676,200	$ 0	$ 57,520	$ 676,167

BUSINESS COMBINATION BUSINESS_2

BUSINESS COMBINATION BUSINESS COMBINATIONS - Pro Forma Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Business Combinations [Abstract]
Business Acquisition, Pro Forma Revenue	$ 484,915	$ 454,579
Business Acquisition, Pro Forma Net Income	$ 221,122	$ 130,402
Business Acquisition, Pro Forma Earnings Per Share, Basic	$ 2.27	$ 1.34
Business Acquisition, Pro Forma Earnings Per Share, Diluted	$ 2.25	$ 1.33

FIRST FINANCIAL BANCORP. (PAR_3

FIRST FINANCIAL BANCORP. (PARENT COMPANY ONLY) FINANCIAL INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Cash	$ 200,691	$ 236,221	$ 236,221	$ 231,054	$ 200,691	$ 236,221	$ 150,650
Other investments				133,198	125,020
Premises and equipment				207,211	214,506
Total assets				15,973,134	14,511,625
Subordinated Debt				321,384	170,967
Other liabilities				516,265	323,134
Total liabilities				13,691,064	12,263,920
Shareholders’ equity				2,282,070	2,247,705	2,078,249	930,664
Total liabilities and shareholders’ equity				15,973,134	14,511,625
Income Statement [Abstract]
Noninterest income	189,123	131,373	103,382
Interest Expense	68,452	123,324	91,147
Salaries and employee benefits	236,779	209,061	188,990
Professional services	9,961	11,254	12,272
Income before income taxes and equity in undistributed net earnings of subsidiaries	184,411	242,862	214,221
Income tax expense (benefit)	28,601	44,787	41,626
Net income	155,810	198,075	172,595
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	191,151	254,900	153,670
Operating activities
Net income	155,810	198,075	172,595
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	33,337	28,138	24,171
Stock-based compensation expense	7,678	7,969	6,219
Deferred income taxes	(8,380)	12,590	6,267
Decrease (increase) in other assets	(288,857)	(165,902)	35,000
Net cash provided by (used in) operating activities	109,888	186,329	260,346
Investing activities
Net cash acquired (paid) in business combinations	0	(51,663)
Cash Acquired from Acquisition			64,895
Proceeds from sales and maturities of investment securities	904,821	557,034	387,351
Purchases of investment securities	(1,551,952)	(834,743)	(852,131)
Net cash provided by (used in) investing activities	(1,204,871)	(252,424)	(204,785)
Financing activities
Net (decrease) increase in short-term borrowings	(1,149,587)	275,490	30,531
Cash dividends paid on common stock	(89,691)	(89,097)	(79,655)
Treasury stock purchase	(16,686)	(66,218)	0
Proceeds from exercise of stock options, net of shares purchased	72	90	284
Net cash provided by (used in) financing activities	1,125,346	30,565	30,010
Cash and due from banks at beginning of year	200,691	236,221	150,650
Cash and due from banks at end of year	231,054	200,691	236,221
Parent Company [Member]
Statement of Financial Position [Abstract]
Cash	55,869	86,878	57,719	172,902	55,869	$ 86,878	$ 57,719
Other investments				1,388	1,116
Subordinated notes from subsidiaries				7,500	7,500
Premises and equipment				1,328	1,344
Other assets				68,812	77,572
Total assets				2,607,498	2,424,652
Subordinated Debt				320,615	171,983
Dividends payable				674	849
Other liabilities				4,139	4,115
Total liabilities				325,428	176,947
Shareholders’ equity				2,282,070	2,247,705
Total liabilities and shareholders’ equity				2,607,498	2,424,652
Income Statement [Abstract]
Interest income	27	30	23
Noninterest income	272	191	0
Dividends from subsidiaries	81,725	196,800	107,340
Total income	82,024	197,021	107,363
Interest Expense	14,172	9,552	8,798
Salaries and employee benefits	8,004	8,169	6,413
Professional services	1,160	1,040	5,130
Other	5,163	6,599	5,648
Total expenses	28,499	25,360	25,989
Income before income taxes and equity in undistributed net earnings of subsidiaries	53,525	171,661	81,374
Income tax expense (benefit)	(6,145)	(5,975)	(6,687)
Equity in undistributed earnings (loss) of subsidiaries	(96,140)	(20,439)	(84,534)
Net income	155,810	198,075	172,595
Operating activities
Net income	155,810	198,075	172,595
Adjustments to reconcile net income to net cash provided by operating activities
Equity in undistributed earnings (loss) of subsidiaries	(96,140)	(20,439)	(84,534)
Depreciation and amortization	712	584	194
Stock-based compensation expense	7,678	7,969	6,219
Deferred income taxes	(158)	1,255	739
(Decrease) increase in dividends payable	(175)	384	(10,500)
(Decrease) increase in other liabilities	(22)	(244)	9,979
Decrease (increase) in other assets	8,635	(7,187)	16,346
Net cash provided by (used in) operating activities	76,340	180,397	111,038
Investing activities
Capital contributions to subsidiaries	0	0	(3,000)
Net cash acquired (paid) in business combinations	0	(53,660)
Cash Acquired from Acquisition			11,353
Proceeds from sales and maturities of investment securities	0	264	0
Purchases of investment securities	0	(500)	0
Net cash provided by (used in) investing activities	0	(53,896)	8,353
Financing activities
Net (decrease) increase in short-term borrowings	0	0	(8,333)
Proceeds from Issuance of Subordinated Long-term Debt	150,000	0	0
Cash dividends paid on common stock	(89,691)	(89,097)	(79,655)
Treasury stock purchase	(16,686)	(66,218)	0
Proceeds from exercise of stock options, net of shares purchased	72	90	284
Other	(3,002)	(2,285)	(2,528)
Net cash provided by (used in) financing activities	40,693	(157,510)	(90,232)
Net increase (decrease) in cash	117,033	(31,009)	29,159
Cash and due from banks at beginning of year	55,869	86,878	57,719
Cash and due from banks at end of year	$ 172,902	$ 55,869	$ 86,878
Commercial Banks [Member] | Parent Company [Member]
Statement of Financial Position [Abstract]
Investment in subsidiaries				2,346,009	2,272,991
Nonbanks [Member] | Parent Company [Member]
Statement of Financial Position [Abstract]
Investment in subsidiaries				9,559	8,260
Subsidiaries [Member] | Parent Company [Member]
Statement of Financial Position [Abstract]
Investment in subsidiaries				$ 2,355,568	$ 2,281,251