CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
INTEREST INCOME:
Loans, including fees	$ 133,958	$ 123,360	$ 124,843
Taxable investment securities	7,046	7,481	8,067
Federal Home Loan Bank stock and other	1,428	1,536	1,658
Total interest income	142,432	132,377	134,568
INTEREST EXPENSE:
Deposits	4,380	3,905	4,093
Securities sold under agreements to repurchase and other short-term borrowings	92	112	70
Federal Home Loan Bank advances	11,934	13,072	14,715
Subordinated note	2,056	2,515	2,515
Total interest expense	18,462	19,604	21,393
NET INTEREST INCOME	123,970	112,773	113,175
Provision for loan and lease losses	5,396	2,859	2,983
NET INTEREST INCOME AFTER PROVISION FOR LOAN AND LEASE LOSSES	118,574	109,914	110,192
NON-INTEREST INCOME:
Service charges on deposit accounts	13,015	13,807	13,954
Net refund transfer fees	17,388	16,130	13,884
Mortgage banking income	4,411	2,862	7,258
Interchange fee income	8,353	7,017	6,927
Bargain purchase gain			1,324
Gain on call of securities available for sale	88
Net gain (loss) on other real estate owned	(301)	(2,218)	346
Increase in cash surrender value of bank owned life insurance	1,402	1,329	86
Other	3,638	3,592	2,451
Total non-interest income	47,994	42,519	46,230
NON-INTEREST EXPENSES:
Salaries and employee benefits	58,091	54,373	57,778
Occupancy and equipment, net	20,689	22,008	21,918
Communication and transportation	3,752	3,866	4,128
Marketing and development	3,161	3,264	3,106
FDIC insurance expense	2,084	1,865	1,682
Bank franchise tax expense	4,734	4,616	4,115
Data processing	4,340	3,513	3,120
Interchange related expense	3,873	3,450	3,063
Supplies	1,101	1,009	1,157
Other real estate owned expense	735	1,024	1,948
Legal and professional fees	3,306	2,766	5,955
Other	7,458	6,364	7,954
Total non-interest expenses	113,324	108,118	115,924
INCOME BEFORE INCOME TAX EXPENSE	53,244	44,315	40,498
INCOME TAX EXPENSE	18,078	15,528	15,075
NET INCOME	$ 35,166	$ 28,787	$ 25,423
Class A Common Stock
BASIC EARNINGS PER SHARE:
Basic earnings per share (in dollars per share)	$ 1.70	$ 1.39	$ 1.23
DILUTED EARNINGS PER SHARE:
Diluted earnings per share (in dollars per share)	1.70	1.38	1.22
DIVIDENDS DECLARED PER COMMON SHARE:
Dividend declared per common share (in dollars per share)	0.781	0.737	0.693
Class B Common Stock
BASIC EARNINGS PER SHARE:
Basic earnings per share (in dollars per share)	1.55	1.32	1.17
DILUTED EARNINGS PER SHARE:
Diluted earnings per share (in dollars per share)	1.54	1.32	1.16
DIVIDENDS DECLARED PER COMMON SHARE:
Dividend declared per common share (in dollars per share)	$ 0.710	$ 0.670	$ 0.630