PARENT COMPANY FINANCIAL INFORMATION (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Assets [Abstract]
Cash on deposit with subsidiary bank	$ 29,239,309	$ 28,204,699
Securities available for sale, at estimated fair value	239,685,763	280,869,810
Other Assets	18,119,801	25,159,322
Total assets	1,248,159,708	1,216,259,587
Liabilities and shareholders' equity: [Abstract]
Dividends payable	0	1,141,081
Other liabilities	11,922,115	9,445,319
Total liabilities	1,117,044,771	1,090,330,147
Shareholders' equity:
Total shareholders' equity	131,114,937	125,929,440	97,408,563	90,085,665
Total liabilities and shareholders' equity	1,248,159,708	1,216,259,587
Statement of Income [Abstract]
Income before income tax expense	16,406,722	15,570,905	15,207,112
Income tax expense (benefit)	5,384,482	5,033,150	5,105,239
Net income	11,022,240	10,537,755	10,101,873
Cash flows from operating activities: [Abstract]
Net income	11,022,240	10,537,755	10,101,873
Adjustments to reconcile net income to net cash provided by operating activities:
Change in other assets	6,083,953	(9,890,546)	2,708,278
Change in other liabilities	587,918	206,721	(959,274)
Net cash provided by operating activities	24,562,149	9,142,072	17,824,381
Cash flow from investing activities:
Net cash used by investing activities	(56,856,819)	(5,063,570)	(8,958,440)
Cash flow from financing activities [Abstract]
Purchase of treasury stock	(635,800)	(501,299)	(425,567)
Sale of treasury stock	257,449	242,610	153,360
Net cash provided (used) by financing activities	19,634,038	(11,796,426)	(27,984,560)
(Decrease) increase in cash and cash equivalents	(12,660,632)	(7,717,924)	(19,118,619)
Cash and cash equivalents, beginning of period	52,901,853	60,619,777	79,738,396
Cash and cash equivalents, end of period	40,241,221	52,901,853	60,619,777
Parent Company [Member]
Assets [Abstract]
Cash on deposit with subsidiary bank	1,788,169	1,122,470
Dividends receivable from subsidiary bank	0	1,141,081
Securities available for sale, at estimated fair value	304,190	307,064
Other Assets	1,813,162	2,578,312
Total assets	131,143,587	127,197,542
Liabilities and shareholders' equity: [Abstract]
Dividends payable	0	1,141,081
Other liabilities	28,650	127,021
Total liabilities	28,650	1,268,102
Shareholders' equity:
Total shareholders' equity	131,114,937	125,929,440
Total liabilities and shareholders' equity	131,143,587	127,197,542
Statement of Income [Abstract]
Dividends from subsidiary bank	4,572,958	11,916,475	3,520,584
Interest and Dividend Income	7,372	8,127	3,451
Other income	150,136	776,672	388,190
Operating Expenses	331,441	227,847	209,794
Income before income tax expense	4,399,025	12,473,427	3,702,431
Income before income tax	10,863,816	10,680,352	10,102,779
Income tax expense (benefit)	(158,424)	142,597	906
Net income	11,022,240	10,537,755	10,101,873
Cash flows from operating activities: [Abstract]
Net income	11,022,240	10,537,755	10,101,873
Adjustments to reconcile net income to net cash provided by operating activities:
Change in dividend receivable	1,141,081	(259,879)	(1,115)
Change in other assets	765,150	(60,510)	(19,789)
Change in other liabilities	48,182	136,602	678,237
Expense related to employee stock compensation	80,000	55,000	55,000
Expense related to restricted stock units for directors' deferred compensation plan	86,717	80,083	111,772
Expense to employee restricted stock awards	79,510	28,141	1,143
Net cash provided by operating activities	6,758,089	12,310,267	4,526,773
Cash flow from investing activities:
Cash paid Fort Orange Financial Corp. acquisition	0	(8,137,816)	0
Net cash used by investing activities	0	(8,137,816)	0
Cash flow from financing activities [Abstract]
Cash dividends paid	(5,714,039)	(4,056,597)	(3,519,470)
Purchase of treasury stock	(635,800)	(501,299)	(425,567)
Sale of treasury stock	257,449	242,610	153,360
Net cash provided (used) by financing activities	(6,092,390)	(4,315,286)	(3,791,677)
(Decrease) increase in cash and cash equivalents	665,699	(142,835)	735,096
Cash and cash equivalents, beginning of period	1,122,470	1,265,305	530,209
Cash and cash equivalents, end of period	1,788,169	1,122,470	1,265,305
Parent Company [Member] | Chemung Canal Trust Company [Member]
Assets [Abstract]
Investment in subsidiary	126,597,837	121,462,184
Statement of Income [Abstract]
Equity in undistributed earnings	6,410,993	(1,837,241)	6,391,013
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings	(6,410,993)	1,837,241	(6,391,013)
Parent Company [Member] | CFS Group Inc [Member]
Assets [Abstract]
Investment in subsidiary	640,229	586,431
Statement of Income [Abstract]
Equity in undistributed earnings	53,798	44,166	9,335
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings	$ (53,798)	$ (44,166)	$ (9,335)