CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net income	$ 144,434	$ 58,914
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	(35,000)	96,646
Depreciation, amortization and accretion, net	27,567	34,058
Deferred income tax provision (benefits)	7,168	(13,786)
Stock-based compensation	6,779	5,596
Other losses (gains)	76	(33)
Originations of loans held for sale	(73,368)	(123,331)
Proceeds from sales of loans held for sale	85,787	120,970
Net gains on sales of loans originated for investment and held for sale	(2,442)	(4,581)
Net (gains) losses on investment securities	(102)	126
Change in assets and liabilities:
Net decrease in other assets	19,740	18,272
Net increase (decrease) in other liabilities	67,557	(84,298)
Net cash provided by operating activities	248,196	108,553
Available-for-sale securities:
Proceeds from maturities and principal repayments	920,073	597,670
Proceeds from calls and sales	2,820	644,703
Purchases	(1,900,080)	(2,195,832)
Other investments:
Proceeds from sales	7,956	18,346
Purchases	(60,155)	(27,562)
Loans:
Net decrease (increase) in loans and leases resulting from originations and principal repayments	183,820	(698,069)
Proceeds from sales of loans originated for investment	2,200	132,011
Purchases of loans	(39,558)	(40,611)
Proceeds from bank-owned life insurance	5,628	1,845
Purchases of premises, equipment and software	(9,689)	(20,646)
Proceeds from sales of premises and equipment	1,394
Proceeds from sales of other real estate owned		316
Other	(2,422)	(1,951)
Net cash used in investing activities	(888,013)	(1,589,780)
Cash flows from financing activities
Net increase in deposits	1,607,392	2,916,640
Repayment of short-term borrowings		(200,000)
Dividends paid	(67,448)	(67,547)
Stock tendered for payment of withholding taxes	(2,845)	(1,661)
Common stock repurchased	(31,928)	(5,000)
Net cash provided by financing activities	1,505,171	2,642,432
Net increase in cash and cash equivalents	865,354	1,161,205
Cash and cash equivalents at beginning of period	1,040,944	694,017
Cash and cash equivalents at end of period	1,906,298	1,855,222
Supplemental disclosures
Interest paid	14,464	37,370
Income taxes paid, net of income tax refunds	30,399	4,242
Noncash investing and financing activities:
Operating lease right-of-use assets obtained in exchange for new lease obligations	7,221	1,965
Transfers from loans and leases to loans held for sale	1,839	130,863
Obligation to fund low-income housing partnerships	$ 15,314	$ 11,369