Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Operating Activities
Net income	$ 101,524	$ 82,943
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	57	5,513
Net amortization of debt securities	8,707	6,835
Net accretion of purchase accounting adjustments	(2,187)	(1,425)
Amortization of debt modification costs	825	825
Origination of loans held for sale	(353,921)	(415,553)
Proceeds from loans held for sale	346,144	425,484
Gain on sale of loans	(13,560)	(14,239)
(Gain) loss on sale of debt securities	(347)	389
Bank-owned life insurance income, net	(1,021)	(1,310)
Stock-based compensation, net of tax benefits	1,850	1,868
Depreciation and amortization of premises and equipment	9,011	7,544
Gain on sale and write-downs of other real estate owned, net	(334)	(81)
Amortization of core deposit intangibles	3,559	2,804
Amortization of investments in variable interest entities	3,885	2,911
Net increase in accrued interest receivable	(3,213)	(4,306)
Net (increase) decrease in other assets	(6,520)	1,048
Net increase in accrued interest payable	749	57
Net decrease in other liabilities	(9,518)	(2,070)
Net cash provided by operating activities	85,690	99,237
Investing Activities
Sales of available-for-sale debt securities	415,093	219,855
Maturities, prepayments and calls of available-for-sale debt securities	247,854	156,482
Purchases of available-for-sale debt securities	(457,915)	(499,552)
Maturities, prepayments and calls of held-to-maturity debt securities	32,575	26,767
Principal collected on loans	1,364,270	1,269,145
Loan originations	(1,675,181)	(1,681,348)
Net additions to premises and equipment	(11,882)	(11,297)
Proceeds from sale of other real estate owned	2,440	1,693
Proceeds from redemption of non-marketable equity securities	76,948	41,393
Purchases of non-marketable equity securities	(71,198)	(40,385)
Proceeds from bank-owned life insurance	0	299
Investments in variable interest entities	(6,451)	(23,072)
Net cash received from acquisitions	11,307	101,268
Net cash used in investing activities	(72,140)	(438,752)
Financing Activities
Net increase in deposits	86,429	528,881
Net increase (decrease) in securities sold under agreements to repurchase	97,091	(30,238)
Net (decrease) increase in short-term Federal Home Loan Bank advances	(120,000)	40,000
Repayments of long-term Federal Home Loan Bank advances	(987)	(528)
Net increase (decrease) in other borrowed funds	54	(9,850)
Cash dividends paid	(47,560)	(19,551)
Tax withholding payments for stock-based compensation	(1,158)	(1,071)
Net cash provided by financing activities	13,869	507,643
Net increase in cash, cash equivalents and restricted cash	27,419	168,128
Cash, cash equivalents and restricted cash at beginning of period	203,790	200,004
Cash, cash equivalents and restricted cash at end of period	231,209	368,132
Supplemental Disclosure of Cash Flow Information
Cash paid during the period for interest	22,244	16,878
Income Taxes Paid	21,680	12,403
Supplemental Disclosure of Non-Cash Investing and Financing Activities
Sale and refinancing of other real estate owned	7	372
Transfer of loans to other real estate owned	1,914	1,144
Right-of-use assets obtained in exchange for operating lease liabilities	3,862	0
Dividends declared but not paid	23,482	22,211
Fair value of common stock shares issued	87,153	250,807
Cash consideration for outstanding shares	4	16,265
Effective settlement of a pre-existing relationship	0	10,054
Fair Value of Assets Acquired	379,155	1,549,158
Liabilities Assumed	$ 291,998	$ 1,383,756