CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities
Net income		$ 52,612	$ 41,680
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of premises and equipment		2,333	2,336
Provision for loan losses		7,600	20,000
Amortization of intangibles		1,068	483
Net accretion of loans		(3,790)	(969)
Accretion on bank premises		(65)	(46)
Accretion on deposits		(917)	(46)
Amortization (accretion) on borrowings		166	(98)
Stock-based compensation expense		2,143	499
Losses on sales of investment securities, net	[1]	280
(Gains) losses on equity securities, net		(340)	325
Gains on sales of loans held-for-sale, net		(343)	(31)
Loans originated for resale		(11,807)	(2,206)
Proceeds from sale of loans held-for sale		10,552	2,337
Net loss on sale of other real estate owned			192
Loss on extinguishment of debt		1,047
Increase in cash surrender value of bank owned life insurance		(2,570)	(1,715)
Amortization of premiums and accretion of discounts on investments securities, net		3,069	2,577
Amortization of subordinated debt issuance costs		246	250
Increase in accrued interest receivable		(376)	(2,220)
Net change in operating leases		1,359
Decrease in other assets		2,483	42
(Decrease) increase in other liabilities		(1,396)	3,945
Net cash provided by operating activities		63,354	67,335
Investment securities available-for-sale:
Purchases		(203,494)	(114,457)
Sales		183,728
Maturities, calls and principal repayments		136,375	115,757
Sales of equity securities		569
Net redemptions of restricted investment in bank stocks		3,190	1,011
Payments on loans held-for-sale			159
Net increase in loans		(239,012)	(283,283)
Purchases of premises and equipment		(1,336)	(1,629)
Purchases of bank owned life insurance		(10,000)
Proceeds from sale of other real estate owned			884
Cash and cash equivalents acquired in acquisition		13,741
Cash consideration paid in acquisition		(2,530)
Net cash used in investing activities		(118,769)	(281,558)
Cash flows from financing activities
Net increase in deposits		243,949	193,683
Increase in subordinated debentures			73,525
Advances of Federal Home Loan Bank ("FHLB") borrowings		1,576,000	1,256,000
Repayments of FHLB borrowings		(1,728,944)	(1,296,000)
Repurchase of stock		(5,175)
Cash dividends paid on common stock		(9,037)	(7,243)
Proceeds from exercise of stock options		265	524
Net cash provided by financing activities		77,058	220,489
Net change in cash and cash equivalents		21,643	6,266
Cash and cash equivalents at beginning of period		172,366	149,582
Cash and cash equivalents at end of period		194,009	155,848
Cash payments for:
Interest paid on deposits and borrowings		67,443	40,200
Income taxes		13,199	2,507
Supplemental disclosures of noncash investing activities
Transfer of loans to other real estate owned		907	538
Transfer of loans held-for-investment to loans held-for-sale		31,647	21,236
Transfer of loans held-for-sale to held-for-investment			45,552
Business combinations:
Fair value of net assets acquired, net of cash and cash equivalents		534,146
Fair value of liabilities assumed		$ 488,475

[1] Not within scope of ASC 606.