Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Activities
Net income	$ 43,339	$ 49,132
Adjustments to reconcile net income to net cash provided by operating activities:
Credit loss expense	22,744	57
Net amortization of debt securities	3,237	5,379
Net amortization (accretion) of purchase accounting adjustments	324	(1,788)
Amortization of debt modification costs	0	412
Origination of loans held for sale	(275,256)	(145,163)
Proceeds from loans held for sale	268,067	154,756
Gain on sale of loans	(11,862)	(5,798)
Gain on sale of debt securities	(863)	(213)
Bank-owned life insurance income, net	(656)	(497)
Stock-based compensation, net of tax benefits	1,199	1,197
Depreciation and amortization of premises and equipment	4,833	4,574
Gain on sale and write-downs of other real estate owned, net	(196)	(416)
Amortization of core deposit intangibles	2,533	1,694
Amortization of investments in variable interest entities	2,114	1,644
Net increase in accrued interest receivable	(10,690)	(2,959)
Net increase in other assets	(9,793)	(1,636)
Net (decrease) increase in accrued interest payable	(99)	457
Net decrease in other liabilities	(13,213)	(14,525)
Net cash provided by operating activities	25,762	46,307
Investing Activities
Sales of available-for-sale debt securities	0	269,616
Maturities, prepayments and calls of available-for-sale debt securities	176,926	120,368
Purchases of available-for-sale debt securities	(811,523)	(311,281)
Maturities, prepayments and calls of held-to-maturity debt securities	20,250	29,945
Principal collected on loans	810,652	617,236
Loan originations	(942,157)	(656,930)
Net additions to premises and equipment	(940)	(3,809)
Proceeds from sale of other real estate owned	1,198	1,208
Proceeds from redemption of non-marketable equity securities	36,244	39,436
Purchases of non-marketable equity securities	(51,598)	(28,000)
Investments in variable interest entities	(2,895)	(576)
Net cash received from acquisitions	43,713	0
Net cash (used in) provided by investing activities	(720,130)	77,213
Financing Activities
Net increase in deposits	178,132	94,322
Net increase in securities sold under agreements to repurchase	3,263	93,470
Net increase (decrease) in short-term Federal Home Loan Bank advances	475,000	(285,000)
Repayments of long-term Federal Home Loan Bank advances	(547)	(896)
Net (decrease) increase in other borrowed funds	(5)	27
Cash dividends paid	(18,652)	(25,562)
Tax withholding payments for stock-based compensation	(977)	(1,144)
Proceeds from stock option exercises	634	0
Net cash provided by (used in) financing activities	636,848	(124,783)
Net decrease in cash, cash equivalents and restricted cash	(57,520)	(1,263)
Cash, cash equivalents and restricted cash at beginning of period	330,961	203,790
Cash, cash equivalents and restricted cash at end of period	273,441	202,527
Supplemental Disclosure of Cash Flow Information
Cash paid during the period for interest	8,595	10,447
Supplemental Disclosure of Non-Cash Investing and Financing Activities
Sale and refinancing of other real estate owned	215	0
Transfer of loans to other real estate owned	465	1,437
Right-of-use assets obtained in exchange for operating lease liabilities	2,241	647
Dividends declared during the period but not paid	27,727	22,039
Fair value of common stock shares issued	112,133	0
Cash consideration	13,721	0
Fair Value of Assets Acquired	744,109	0
Liabilities Assumed	$ 618,255	$ 0