Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating Activities
Net income	$ 101,421	$ 90,090
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	7,938	1,194
Net amortization of investment securities premiums and discounts	16,265	19,990
Net accretion of purchase accounting adjustments	(4,534)	(1,413)
Loans held for sale originated or acquired	(672,055)	(789,605)
Proceeds from sales of loans held for sale	730,082	816,236
Gain on sale of loans	(23,031)	(23,841)
Loss on sale of investments	545	706
Bank-owned life insurance income, net	(1,032)	(814)
Stock-based compensation	3,129	2,225
Net tax benefits from stock-based compensation	(1,680)	(793)
Depreciation of premises and equipment	10,989	11,440
Gain on sale of other real estate owned and write-downs, net	(1,808)	(103)
Amortization of core deposit intangibles	1,880	2,362
Amortization of investments in variable interest entities	3,581	1,745
Net increase in accrued interest receivable	(3,564)	(5,449)
Net decrease in other assets	6,147	5,820
Net decrease in accrued interest payable	(431)	(84)
Net increase (decrease) in other liabilities	4,609	(1,182)
Net cash provided by operating activities	178,451	128,524
Investing Activities
Sales of available-for-sale securities	247,748	20,539
Maturities, prepayments and calls of available-for-sale securities	347,450	527,596
Purchases of available-for-sale securities	(28,301)	(217,261)
Maturities, prepayments and calls of held-to-maturity securities	18,910	21,965
Purchases of held-to-maturity securities	0	(1,222)
Principal collected on loans	1,472,757	1,276,078
Loans originated or acquired	(2,022,508)	(1,755,185)
Net additions to premises and equipment	(7,682)	(6,893)
Proceeds from sale of other real estate owned	11,812	8,793
Proceeds from sale of non-marketable equity securities	47,805	69,607
Purchases of non-marketable equity securities	(42,598)	(61,999)
Proceeds from bank-owned life insurance	437	294
Investments in variable interest entities	(16,541)	(3,751)
Net cash (paid) received in acquisitions	(4,091)	6,701
Net cash provided by (used in) investing activities	25,198	(114,738)
Financing Activities
Net increase in deposits	98,013	305,035
Net decrease in securities sold under agreements to repurchase	(20,054)	(22,171)
Net decrease in short-term Federal Home Loan Bank advances	(62,800)	(140,000)
Proceeds from long-term Federal Home Loan Bank advances	150,000	0
Repayments of long-term Federal Home Loan Bank advances	(208,097)	(45,491)
Net increase in other borrowed funds	3,803	994
Cash dividends paid	(95,332)	(53,393)
Tax withholding payments for stock-based compensation	(1,513)	(600)
Net cash (used in) provided by financing activities	(135,980)	44,374
Net increase in cash and cash equivalents	67,669	58,160
Cash and cash equivalents at beginning of period	152,541	193,253
Cash and cash equivalents at end of period	220,210	251,413
Supplemental Disclosure of Cash Flow Information
Cash paid during the period for interest	23,223	22,506
Cash paid during the period for income taxes	29,315	25,254
Supplemental Disclosure of Non-Cash Investing Activities
Sale and refinancing of other real estate owned	531	611
Transfer of loans to other real estate owned	3,844	4,117
Dividends declared but not paid	232	15,409
Fair value of common stock shares issued	46,673	10,465
Cash consideration for outstanding shares	17,342	3,475
Fair Value of Assets Acquired	355,230	69,750
Liabilities Assumed	$ 321,824	$ 62,225