Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Activities
Net income	$ 19,606,000	$ 46,058,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	39,532,000	10,444,000
Depreciation of premises, furniture, and equipment	4,169,000	4,050,000
Net amortization of premium on securities	5,727,000	2,672,000
Net securities losses	1,005,000	0
Gains on sales of 1-4 family mortgages and corporate loans held-for-sale	(2,629,000)	(1,410,000)
Net losses (gains) on sales and valuation adjustments of OREO	128,000	(792,000)
Amortization of the FDIC indemnification asset	302,000	302,000
Net losses on sales and valuation adjustments of premises, furniture, and equipment	105,000	391,000
BOLI income	(1,982,000)	(1,826,000)
Share-based compensation expense	3,922,000	3,679,000
Tax benefit related to share-based compensation	62,000	55,000
Amortization of other intangible assets	2,770,000	2,363,000
Originations of mortgage loans held-for-sale	(104,694,000)	(62,895,000)
Proceeds from sales of mortgage loans held-for-sale	119,159,000	58,783,000
Net decrease (increase) in equity securities	2,038,000	(2,498,000)
Net (increase) decrease in accrued interest receivable and other assets	(114,028,000)	27,948,000
Net decrease in accrued interest payables and other liabilities	(40,870,000)	(37,870,000)
Net cash (used in) provided by operating activities	(65,678,000)	49,454,000
Investing Activities
Proceeds from maturities, repayments, and calls of securities available-for-sale	229,391,000	77,601,000
Proceeds from sales of securities available-for-sale	39,095,000	0
Purchases of securities available-for-sale	(586,292,000)	(131,707,000)
Proceeds from maturities, repayments, and calls of securities held-to-maturity	2,268,000	162,000
Purchases of securities held-to-maturity	(16,000)	(2,828,000)
Net purchases of FHLB stock	(38,948,000)	(5,488,000)
Net increase in loans	(373,138,000)	(131,221,000)
Premiums paid on BOLI, net of proceeds from claims	2,003,000	2,660,000
Proceeds from sales of OREO	230,000	2,795,000
Proceeds from sales of premises, furniture, and equipment	0	557,000
Purchases of premises, furniture, and equipment	(3,168,000)	(5,081,000)
Net cash received from (paid for) acquisition	142,282,000	(11,489,000)
Net cash used in investing activities	(586,293,000)	(204,039,000)
Financing Activities
Net (decrease) increase in deposit accounts	(102,404,000)	76,870,000
Net increase in borrowed funds	977,920,000	67,773,000
Repurchases of common stock	(22,557,000)	0
Cash dividends paid	(15,431,000)	(12,782,000)
Restricted stock activity	(3,166,000)	(3,775,000)
Net cash provided by financing activities	834,362,000	128,086,000
Net increase (decrease) in cash and cash equivalents	182,391,000	(26,499,000)
Cash and cash equivalents at beginning of period	299,221,000	289,258,000
Cash and cash equivalents at end of period	481,612,000	262,759,000
Supplemental Disclosures of Cash Flow Information:
Income taxes paid	1,029,000	321,000
Interest paid to depositors and creditors	28,285,000	23,707,000
Dividends declared, but unpaid	15,854,000	12,728,000
Stock issued for acquisitions, net of issuance costs	71,883,000	3,284,000
Non-cash transfers of loans to OREO	121,000	0
Non-cash transfers of loans held-for-investment to loans held-for-sale	3,155,000	2,630,000
Non-cash recognition of right-of-use asset/liability	$ 0	$ 143,561,000