ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY (Balance In The Allowance For Loan Losses And The Recorded Investment In Loans By Portfolio Management) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	$ 51,817	$ 51,260	$ 53,400	$ 45,007	$ 45,007
Provision for loan losses	0	2,400	1,299	10,900	13,800
Loans charged-off	(483)	(2,099)	(4,067)	(5,048)	(6,829)
Recoveries	578	512	1,280	1,214	1,422
Net loans charged-off	95	(1,587)	(2,787)	(3,834)	(5,407)
Balance September 30,	51,912	52,073	51,912	52,073	53,400
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	35,928		35,928		35,074
Valuation allowance	51,912	52,073	51,912	52,073	53,400
Loans:
Loans individually evaluated for impairment	61,303		61,303		63,516
Loans collectively evaluated for impairment	2,142,085		2,142,085		2,170,193
Total ending loans balance	2,203,388		2,203,388		2,233,709
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	19,696	22,999	22,830	21,479	21,479
Provision for loan losses	1,532	1,171	380	3,048	3,112
Loans charged-off	(98)	(883)	(2,552)	(1,470)	(2,587)
Recoveries	224	465	696	695	826
Net loans charged-off	126	(418)	(1,856)	(775)	(1,761)
Balance September 30,	21,354	23,752	21,354	23,752	22,830
Ending allowance balance attributable to loans:
Individually evaluated for impairment	6,571		6,571		9,443
Collectively evaluated for impairment	14,783		14,783		13,387
Valuation allowance	21,354	23,752	21,354	23,752	22,830
Loans:
Loans individually evaluated for impairment	20,319		20,319		24,204
Loans collectively evaluated for impairment	808,700		808,700		727,160
Total ending loans balance	829,019		829,019		751,364
Commercial Real Estate and Multi-Family Residential Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	24,083	20,032	23,489	15,893	15,893
Provision for loan losses	(1,236)	2,134	158	7,362	9,748
Loans charged-off	(112)	(557)	(959)	(1,973)	(2,514)
Recoveries	120	10	167	327	362
Net loans charged-off	8	(547)	(792)	(1,636)	(2,152)
Balance September 30,	22,855	21,619	22,855	21,619	23,489
Ending allowance balance attributable to loans:
Individually evaluated for impairment	8,869		8,869		8,382
Collectively evaluated for impairment	13,986		13,986		15,107
Valuation allowance	22,855	21,619	22,855	21,619	23,489
Loans:
Loans individually evaluated for impairment	37,924		37,924		35,794
Loans collectively evaluated for impairment	746,439		746,439		815,883
Total ending loans balance	784,363		784,363		851,677
Agri-business and Agricultural Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	1,419	948	695	1,318	1,318
Provision for loan losses	(76)	(194)	648	(564)	(520)
Loans charged-off	0	(103)	0	(103)	(103)
Recoveries	1	0	0	0	0
Net loans charged-off	1	(103)	1	(103)	(103)
Balance September 30,	1,344	651	1,344	651	695
Ending allowance balance attributable to loans:
Individually evaluated for impairment	67		67		213
Collectively evaluated for impairment	1,277		1,277		482
Valuation allowance	1,344	651	1,344	651	695
Loans:
Loans individually evaluated for impairment	820		820		853
Loans collectively evaluated for impairment	213,350		213,350		237,150
Total ending loans balance	214,170		214,170		238,003
Other Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	176	560	65	270	270
Provision for loan losses	(207)	(536)	(100)	(246)	(205)
Loans charged-off	0	0	0	0	0
Recoveries	182	0	186	0	0
Net loans charged-off	182	0	186	0	0
Balance September 30,	151	24	151	24	65
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	151		151		65
Valuation allowance	151	24	151	24	65
Loans:
Loans individually evaluated for impairment	0		0		0
Loans collectively evaluated for impairment	44,974		44,974		58,249
Total ending loans balance	44,974		44,974		58,249
Consumer 1-4 Family Mortgage Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	2,412	2,658	2,322	1,694	1,694
Provision for loan losses	356	(272)	417	1,390	1,632
Loans charged-off	(196)	(292)	(288)	(1,009)	(1,050)
Recoveries	21	5	121	24	46
Net loans charged-off	(175)	(287)	(146)	(985)	(1,004)
Balance September 30,	2,593	2,099	2,593	2,099	2,322
Ending allowance balance attributable to loans:
Individually evaluated for impairment	459		459		288
Collectively evaluated for impairment	2,134		2,134		2,034
Valuation allowance	2,593	2,099	2,593	2,099	2,322
Loans:
Loans individually evaluated for impairment	2,194		2,194		2,665
Loans collectively evaluated for impairment	284,027		284,027		285,791
Total ending loans balance	286,221		286,221		288,456
Other Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	523	605	645	682	682
Provision for loan losses	114	294	125	320	350
Loans charged-off	(77)	(264)	(268)	(493)	(575)
Recoveries	30	32	88	158	188
Net loans charged-off	(47)	(232)	(180)	(335)	(387)
Balance September 30,	590	667	590	667	645
Ending allowance balance attributable to loans:
Individually evaluated for impairment	18		18		0
Collectively evaluated for impairment	572		572		645
Valuation allowance	590	667	590	667	645
Loans:
Loans individually evaluated for impairment	46		46		0
Loans collectively evaluated for impairment	44,595		44,595		45,960
Total ending loans balance	44,641		44,641		45,960
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance July 1,	3,508	3,458	3,354	3,671	3,671
Provision for loan losses	(483)	(197)	(329)	(410)	(317)
Loans charged-off	0	0	0	0	0
Recoveries	0	0	0	0	0
Net loans charged-off	0	0	0	0	0
Balance September 30,	3,025	3,261	3,025	3,261	3,354
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	3,025		3,025		3,354
Valuation allowance	3,025	3,261	3,025	3,261	3,354
Loans:
Loans individually evaluated for impairment	0		0		0
Loans collectively evaluated for impairment	0		0		0
Total ending loans balance	$ 0		$ 0		$ 0