CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES
Net income			$ 41,517	$ 29,804
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation			3,889	3,257
Provision for loan/lease losses	$ 2,012	$ 6,206	6,087	11,046
Stock-based compensation expense			1,869	1,106
Deferred compensation expense accrued			2,087	1,453
Losses on other real estate owned, net			3,205	49
Amortization of premiums on securities, net			1,339	1,201
Securities losses, net			56
Loans originated for sale			(104,824)	(39,923)
Proceeds on sales of loans			97,916	38,954
Gains on sales of residential real estate loans	(890)	(337)	(1,748)	(539)
Gains on sales of government guaranteed portions of loans	(519)	(46)	(589)	(405)
Losses on debt extinguishment, net	148		148
Gains on sales of premises and equipment			(67)
Amortization of intangibles	560	542	1,706	1,151
Accretion of acquisition fair value adjustments, net			(3,413)	(2,951)
Increase in cash value of bank-owned life insurance			(1,441)	(1,292)
Increase in other assets			(1,953)	(8,293)
Increase in other liabilities			336	2,254
Net cash provided by operating activities			46,120	36,872
CASH FLOWS FROM INVESTING ACTIVITIES
Net decrease (increase) in federal funds sold			17,098	(2,873)
Net decrease (increase) in interest-bearing deposits at financial institutions			(57,180)	22,099
Proceeds from sales of other real estate owned			840	1,288
Activity in securities portfolio:
Purchases			(28,119)	(66,420)
Calls, maturities and redemptions			9,074	22,915
Paydowns			36,649	36,279
Sales			33,128	1,938
Activity in restricted investment securities:
Purchases			(5,682)	(5,352)
Redemptions			5,006	109
Net increase in loans/leases originated and held for investment			(237,286)	(208,738)
Purchase of premises and equipment			(8,755)	(7,112)
Proceeds from sales of premises and equipment			146
Net cash paid for acquisition				(3,747)
Net cash (used in) investing activities			(235,081)	(209,614)
CASH FLOWS FROM FINANCING ACTIVITIES
Net increase in deposit accounts			276,960	82,309
Net decrease in short-term borrowings			(9,091)	(2,207)
Activity in Federal Home Loan Bank advances:
Term advances			25,000
Calls and maturities			(35,000)	(27,000)
Net change in short-term and overnight advances			(15,965)	120,330
Prepayments	(30,200)		(30,228)
Activity in other borrowings:
Proceeds from other borrowings				9,000
Calls, maturities and scheduled principal payments			(11,937)	(10,613)
Prepayments			(46,313)
Paydown of revolving line of credit			(9,000)
Proceeds from subordinated notes			63,393
Payment of cash dividends on common stock			(2,822)	(2,362)
Proceeds from issuance of common stock, net			1,143	970
Net cash provided by financing activities			206,140	170,427
Net increase (decrease) in cash and due from banks			17,179	(2,315)
Cash and due from banks, beginning			85,523	75,722	$ 75,722
Cash and due from banks, ending	102,702	73,407	102,702	73,407	85,523
Cash and due from banks	91,671	73,407	91,671	73,407	$ 85,523
Cash included in assets held for sale	$ 11,031		11,031
Supplemental disclosure of cash flow information, cash payments (receipts) for:
Interest			45,826	23,102
Income/franchise taxes			769	1,100
Supplemental schedule of noncash investing activities:
Change in accumulated other comprehensive income, unrealized gains on securities available for sale and derivative instruments, net			5,130	(5,148)
Exchange of shares of common stock in connection with payroll taxes for restricted stock and in connection with stock options exercised			(189)	(662)
Transfers of loans to other real estate owned			1,049	46
Increase (decrease) in the fair value of back-to-back interest rate swap assets and liabilities			80,760	(2,441)
Dividends payable			$ 944	938
Transfer of equity securities from securities available for sale to other assets at fair value				2,614
Fair value of assets acquired:
Cash and due from banks		4,587		4,587
Interest-bearing deposits at financial institutions		62,925		62,925
Securities		4,845		4,845
Loans receivable, net		477,337		477,337
Bank-owned life insurance		7,092		7,092
Premises and equipment, net		6,092		6,092
Restricted investment securities		3,654		3,654
Intangibles		8,209		8,209
Other assets		988		988
Total assets acquired		575,729		575,729
Fair value of liabilities assumed:
Deposits		439,580		439,580
Short-term borrowings		1,144		1,144
FHLB advances		73,610		73,610
Other borrowings		9,544		9,544
Other liabilities		8,408		8,408
Total liabilities assumed		532,286		532,286
Net assets acquired		$ 43,443		43,443
Consideration paid:
Cash paid				8,334
Common stock				80,637
Total consideration paid				88,971
Goodwill				45,528
Springfield Bancshares
Consideration paid:
Cash paid				$ 3,747