CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Operating activities:
Net income	$ 44,642	$ 29,383	$ 40,291	$ 87,976
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization			14,915	10,006
Provision for credit losses	7,003	1,524	90,158	3,029	$ 4,684
Share based compensation expense			2,824	2,259
Tax (expense)/ benefit associated with share based compensation			(162)	75
Deferred income tax expense/ (benefit)			(22,965)	455
Origination of loans held for sale			(1,042,787)	(638,820)
Proceeds from sales of loans held for sale			1,025,610	590,997
Gains on sales of loans held for sale			(17,850)	(8,225)
Losses on sales of other real estate owned			32	173
Investment securities gains	(51)	(15)	(432)	(20)
Net (increase)/ decrease in accrued interest receivable			(17,243)	1,171
Net (increase)/ decrease in other assets			1,812	(3,997)
Net increase/ (decrease) in accrued expenses and other liabilities			5,173	(4,510)
Other – net			2,922	2,341
Net cash provided by operating activities			82,298	42,910
Investing activities:
(Purchases of)/ proceeds from other equity securities			(6,321)
(Purchases of)/ proceeds from other equity securities				21,451
Purchases of investments available-for-sale			(529,522)	(83,835)
Proceeds from sales of investments available-for-sale			121,357	0
Proceeds from maturities, calls and principal payments of investments available-for-sale			329,197	141,880
Net increase in loans			(1,107,824)	(25,327)
Proceeds from the sales of other real estate owned			60	324
Cash paid for the acquisition of business activity of RPJ, net of cash acquired			(26,925)	0
Cash acquired in the acquisition of business activity of Revere Bank, net of cash paid			80,466	0
Expenditures for premises and equipment			(3,399)	(4,269)
Net cash provided by/ (used in) investing activities			(1,142,911)	50,224
Financing activities:
Net increase in deposits			1,202,228	579,019
Net increase/ (decrease) in retail repurchase agreements and federal funds purchased			249,101	(201,421)
Proceeds from advances from FHLB			400,000	2,123,000
Repayment of advances from FHLB			(637,982)	(2,454,134)
Retirement of subordinated debt			(10,310)	0
Proceeds from issuance of common stock			1,474	1,068
Stock tendered for payment of withholding taxes			(463)	(702)
Repurchase of common stock			(25,702)	0
Dividends paid			(38,953)	(31,509)
Net cash provided by financing activities			1,139,393	15,321
Net increase in cash and cash equivalents			78,780	108,455
Cash and cash equivalents at beginning of period			146,103	101,481	101,481
Cash and cash equivalents at end of period	$ 224,883	$ 209,936	224,883	209,936	$ 146,103
Supplemental disclosures:
Interest payments			47,105	65,481
Income tax payments, net of refunds of $1,924 in 2020			28,099	23,417
Transfer from loans to other real estate owned			$ 0	$ 414