Retirement Benefit Plans (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018		Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match, maximum		5.00%
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		$ 53,571	$ 53,571		$ 48,445		$ 53,571
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		53,571
Fair Value of Plan Assets, End of Period		48,445	53,571
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		$ 53,571	$ 53,571		$ 48,445		$ 53,571
Percent of Total					100.00%		100.00%
Expected Future Benefit Payments [Abstract]
Health Care Cost Trend Rate Assumed for Next Year					7.00%		7.25%
Rate to which the Cost Trend Rate is Assumed to Decline (the Ultimate Trend Rate)					3.78%		3.89%
Year that the Rate Reaches the Ultimate Trend Rate		2075	2075
Effect of One Percentage Point Increase on Service and Interest Cost Components		$ 42
Effect of One Percentage Point Decrease on Service and Interest Cost Components		(36)
Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation		478
Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation		(417)
Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		53,571	$ 53,571		$ 48,445		$ 53,571
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		53,571
Fair Value of Plan Assets, End of Period		48,445	53,571
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		53,571	53,571		48,445		53,571
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Cash
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		22	22		0		22
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		22
Fair Value of Plan Assets, End of Period		0	22
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		22	22		$ 0		$ 22
Percent of Total					0.00%		0.00%
Cash | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		22	22		$ 0		$ 22
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		22
Fair Value of Plan Assets, End of Period		0	22
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		22	22		0		22
Cash | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Cash | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Interest-Bearing Money Market Fund
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		2,682	2,682		3,310		2,682
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		2,682
Fair Value of Plan Assets, End of Period		3,310	2,682
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		2,682	2,682		$ 3,310		$ 2,682
Percent of Total					6.80%		5.00%
Interest-Bearing Money Market Fund | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		2,682	2,682		$ 3,310		$ 2,682
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		2,682
Fair Value of Plan Assets, End of Period		3,310	2,682
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		2,682	2,682		3,310		2,682
Interest-Bearing Money Market Fund | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Interest-Bearing Money Market Fund | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Common Stock
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		5,657	5,657		5,381		5,657
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		5,657
Fair Value of Plan Assets, End of Period		5,381	5,657
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		5,657	5,657		$ 5,381		$ 5,657
Percent of Total					11.10%	[1]	10.60%
Common Stock | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		5,657	5,657		$ 5,381		$ 5,657
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		5,657
Fair Value of Plan Assets, End of Period		5,381	5,657
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		5,657	5,657		5,381		5,657
Common Stock | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Common Stock | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
North Country Funds - Equity
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	19,680	19,680		16,629		19,680
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	19,680
Fair Value of Plan Assets, End of Period	[2]	16,629	19,680
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	19,680	19,680		$ 16,629		$ 19,680
Percent of Total	[2]				34.30%		36.70%
North Country Funds - Equity | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	19,680	19,680		$ 16,629		$ 19,680
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	19,680
Fair Value of Plan Assets, End of Period	[2]	16,629	19,680
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	19,680	19,680		16,629		19,680
North Country Funds - Equity | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	0
Fair Value of Plan Assets, End of Period	[2]	0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
North Country Funds - Equity | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	0
Fair Value of Plan Assets, End of Period	[2]	0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
Other Mutual Funds - Equity
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		15,168	15,168		13,081		15,168
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		15,168
Fair Value of Plan Assets, End of Period		13,081	15,168
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		15,168	15,168		$ 13,081		$ 15,168
Percent of Total					27.00%		28.30%
Other Mutual Funds - Equity | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		15,168	15,168		$ 13,081		$ 15,168
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		15,168
Fair Value of Plan Assets, End of Period		13,081	15,168
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		15,168	15,168		13,081		15,168
Other Mutual Funds - Equity | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Other Mutual Funds - Equity | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Equity Funds
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		34,848	34,848		29,710		34,848
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		34,848
Fair Value of Plan Assets, End of Period		29,710	34,848
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		34,848	34,848		$ 29,710		$ 34,848
Percent of Total					61.30%		65.00%
Equity Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		34,848	34,848		$ 29,710		$ 34,848
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		34,848
Fair Value of Plan Assets, End of Period		29,710	34,848
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		34,848	34,848		29,710		34,848
Equity Funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Equity Funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
North Country Funds - Fixed Income
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	8,388	8,388		8,124		8,388
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	8,388
Fair Value of Plan Assets, End of Period	[2]	8,124	8,388
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	8,388	8,388		$ 8,124		$ 8,388
Percent of Total	[2]				16.80%		15.70%
North Country Funds - Fixed Income | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	8,388	8,388		$ 8,124		$ 8,388
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	8,388
Fair Value of Plan Assets, End of Period	[2]	8,124	8,388
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	8,388	8,388		8,124		8,388
North Country Funds - Fixed Income | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	0
Fair Value of Plan Assets, End of Period	[2]	0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
North Country Funds - Fixed Income | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period	[2]	0
Fair Value of Plan Assets, End of Period	[2]	0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets	[2]	0	0		0		0
Other Mutual Funds - Fixed Income
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		1,974	1,974		1,920		1,974
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		1,974
Fair Value of Plan Assets, End of Period		1,920	1,974
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		1,974	1,974		$ 1,920		$ 1,974
Percent of Total					4.00%		3.70%
Other Mutual Funds - Fixed Income | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		1,974	1,974		$ 1,920		$ 1,974
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		1,974
Fair Value of Plan Assets, End of Period		1,920	1,974
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		1,974	1,974		1,920		1,974
Other Mutual Funds - Fixed Income | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Other Mutual Funds - Fixed Income | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Fixed Income Funds
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		10,362	10,362		10,044		10,362
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		10,362
Fair Value of Plan Assets, End of Period		10,044	10,362
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		10,362	10,362		$ 10,044		$ 10,362
Percent of Total					20.80%		19.40%
Fixed Income Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		10,362	10,362		$ 10,044		$ 10,362
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		10,362
Fair Value of Plan Assets, End of Period		10,044	10,362
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		10,362	10,362		10,044		10,362
Fixed Income Funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Fixed Income Funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0		0		0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0
Fair Value of Plan Assets, End of Period		0	0
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Fair Value of Plan Assets		0	0		0		0
Employees' Pension Plan
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		53,571	50,220	$ 50,220	48,445		53,571
Benefit Obligation		38,921	36,154	36,154	38,069		38,921
Funded Status of Plan					10,376		14,650
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning of Period		38,921	36,154
Service Cost		1,557	1,392	1,400
Interest Cost		1,598	1,682	1,641
Plan Participants' Contributions		0	0
Amendments		0	0
Actuarial Loss		(795)	2,440
Benefits Paid		(3,212)	(2,747)
Benefit Obligation, End of Period		38,069	38,921	36,154
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		53,571	50,220
Actual Return on Plan Assets		(1,914)	6,098
Employer Contributions		0	0
Plan Participants' Contributions		0	0
Benefits Paid		(3,212)	(2,747)
Fair Value of Plan Assets, End of Period		48,445	53,571	50,220
Accumulated Benefit Obligation at December 31, 2012					37,749
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Prepaid Benefit Cost					10,376		14,650
Accrued Benefit Liability					0		0
Net Benefit Cost Recognized					10,376		14,650
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Net Retirement Plan Loss, Before-Tax Amount		4,480	(517)	(2,657)
Net prior Service Cost Arising During the Period		0	0	0
Amortization of Net Loss		(194)	(306)	(591)
Accretion of Net Retirement Plan Prior Service Credit, Tax (Expense) Benefit		49	57	57
Total Other Comprehensive (Loss) Income for Pension and Other Postretirement Benefit Plans		4,335	(766)	(3,191)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net Actuarial Loss					10,942		6,656
Prior Service (Credit) Cost					313		264
Total Accumulated Other Comprehensive Income, Before Tax					11,255		$ 6,920
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Net Actuarial Loss					612
Prior Service (Credit) Cost					$ 69
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service Cost		1,557	1,392	1,400
Interest Cost		1,598	1,682	1,641
Expected Return on Plan Assets		(3,362)	(3,141)	(3,198)
Amortization of Prior Service (Credit) Cost		(49)	(57)	(57)
Amortization of Net Loss		194	306	591
Net Periodic Benefit Cost		$ (62)	$ 182	$ 377
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount Rate					4.81%		4.24%
Rate of Compensation Increase					3.50%		3.50%
Interest Rate Credit for Determining Projected Cash Balance Account					3.36%		3.00%
Interest Rate to Annuitize Cash Balance Account					3.43%		4.25%
Interest Rate to Convert Annuities to Actuarially Equivalent Lump Sum Account							4.25%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount Rate		4.24%	4.83%	4.73%
Expected Long-Term Return on Assets		6.50%	6.50%	7.00%
Rate of Compensation Increase		3.50%	3.50%	3.50%
Interest Rate Credit for Determining Projected Cash Balance Account		3.00%	3.00%	3.03%
Interest Rate to Annuitize Cash Balance Account			4.50%	5.00%
Interest Rate to Convert Accuities to Actuarially Equivalent Lump Sum Amounts			4.50%	5.00%
Fair Value of Plan Assets		$ 53,571	$ 50,220	$ 50,220	$ 48,445		$ 53,571
Expected Future Benefit Payments [Abstract]
2019					2,223
2020					2,792
2021					2,513
2022					2,756
2023					2,781
2022- 2026					15,162
Estimated Contributions During 2015					0
Select Executive Retirement Plan
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0	0	0		0
Benefit Obligation		4,586	4,547	4,547	4,710		4,586
Funded Status of Plan					(4,710)		(4,586)
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning of Period		4,586	4,547
Service Cost		414	45	40
Interest Cost		192	209	206
Plan Participants' Contributions		0	0
Amendments		0	0
Actuarial Loss		(17)	245
Benefits Paid		(465)	(460)
Benefit Obligation, End of Period		4,710	4,586	4,547
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0	0
Actual Return on Plan Assets		0	0
Employer Contributions		465	460
Plan Participants' Contributions		0	0
Benefits Paid		(465)	(460)
Fair Value of Plan Assets, End of Period		0	0	0
Accumulated Benefit Obligation at December 31, 2012					4,672
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Prepaid Benefit Cost					0		0
Accrued Benefit Liability					(4,710)		(4,586)
Net Benefit Cost Recognized					(4,710)		(4,586)
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Net Retirement Plan Loss, Before-Tax Amount		(17)	244	(32)
Net prior Service Cost Arising During the Period		0	0	0
Amortization of Net Loss		(131)	(129)	(125)
Accretion of Net Retirement Plan Prior Service Credit, Tax (Expense) Benefit		(57)	(57)	(57)
Total Other Comprehensive (Loss) Income for Pension and Other Postretirement Benefit Plans		(205)	58	(214)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net Actuarial Loss					1,979		2,127
Prior Service (Credit) Cost					432		489
Total Accumulated Other Comprehensive Income, Before Tax					2,411		$ 2,616
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Net Actuarial Loss					106
Prior Service (Credit) Cost					$ 54
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service Cost		414	45	40
Interest Cost		192	209	206
Expected Return on Plan Assets		0	0	0
Amortization of Prior Service (Credit) Cost		57	57	57
Amortization of Net Loss		131	129	125
Net Periodic Benefit Cost		$ 794	$ 440	$ 428
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount Rate					4.80%		4.18%
Rate of Compensation Increase					3.50%		3.50%
Interest Rate Credit for Determining Projected Cash Balance Account					3.36%		3.00%
Interest Rate to Annuitize Cash Balance Account					4.46%		4.25%
Interest Rate to Convert Annuities to Actuarially Equivalent Lump Sum Account							4.25%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount Rate		4.18%	4.73%	4.61%
Rate of Compensation Increase		3.50%	3.50%	3.50%
Interest Rate Credit for Determining Projected Cash Balance Account		3.00%	3.00%	3.03%
Interest Rate to Annuitize Cash Balance Account			4.50%	5.00%
Interest Rate to Convert Accuities to Actuarially Equivalent Lump Sum Amounts			4.50%	5.00%
Fair Value of Plan Assets		$ 0	$ 0	$ 0	$ 0		$ 0
Expected Future Benefit Payments [Abstract]
2019					447
2020					432
2021					416
2022					399
2023					381
2022- 2026					2,683
Estimated Contributions During 2015					447
Postretirement Benefit Plans
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Fair Value of Plan Assets		0	0	0	0		0
Benefit Obligation		7,727	7,623	7,623	7,706		7,727
Funded Status of Plan					(7,706)		(7,727)
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning of Period		7,727	7,623
Service Cost		136	130	147
Interest Cost		333	339	340
Plan Participants' Contributions		416	492
Amendments		453	0
Actuarial Loss		(664)	(14)
Benefits Paid		(695)	(843)
Benefit Obligation, End of Period		7,706	7,727	7,623
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning of Period		0	0
Actual Return on Plan Assets		0	0
Employer Contributions		279	351
Plan Participants' Contributions		416	492
Benefits Paid		(695)	(843)
Fair Value of Plan Assets, End of Period		0	0	0
Accumulated Benefit Obligation at December 31, 2012					7,706
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Prepaid Benefit Cost					0		0
Accrued Benefit Liability					(7,706)		(7,727)
Net Benefit Cost Recognized					(7,706)		(7,727)
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Net Retirement Plan Loss, Before-Tax Amount		(665)	(14)	(328)
Net prior Service Cost Arising During the Period		453	0	0
Amortization of Net Loss		0	24	0
Accretion of Net Retirement Plan Prior Service Credit, Tax (Expense) Benefit		(100)	11	12
Total Other Comprehensive (Loss) Income for Pension and Other Postretirement Benefit Plans		(312)	21	(316)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net Actuarial Loss					(893)		(228)
Prior Service (Credit) Cost					786		433
Total Accumulated Other Comprehensive Income, Before Tax					(107)		$ 205
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Net Actuarial Loss					(70)
Prior Service (Credit) Cost					$ 101
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service Cost		136	130	147
Interest Cost		333	339	340
Expected Return on Plan Assets		0	0	0
Amortization of Prior Service (Credit) Cost		100	(11)	(12)
Amortization of Net Loss		0	(24)	0
Net Periodic Benefit Cost		$ 569	$ 434	$ 475
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount Rate					4.81%		4.22%
Rate of Compensation Increase					3.50%		3.50%
Interest Rate to Annuitize Cash Balance Account					4.88%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount Rate		4.22%	4.80%	4.69%
Rate of Compensation Increase		3.50%	3.50%	3.50%
Fair Value of Plan Assets		$ 0	$ 0	$ 0	$ 0		$ 0
Expected Future Benefit Payments [Abstract]
2019					580
2020					594
2021					639
2022					626
2023					614
2022- 2026					3,212
Estimated Contributions During 2015					$ 580
Minimum | Cash
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					0.00%		0.00%
Minimum | Interest-Bearing Money Market Fund
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					0.00%		0.00%
Minimum | Common Stock
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					0.00%		0.00%
Minimum | North Country Funds - Equity
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Minimum | Other Mutual Funds - Equity
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Minimum | Equity Funds
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					55.00%		55.00%
Minimum | North Country Funds - Fixed Income
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Minimum | Other Mutual Funds - Fixed Income
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Minimum | Fixed Income Funds
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					10.00%		10.00%
Maximum | Cash
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					15.00%		15.00%
Maximum | Interest-Bearing Money Market Fund
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					15.00%		15.00%
Maximum | Common Stock
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					10.00%		10.00%
Maximum | North Country Funds - Equity
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Maximum | Other Mutual Funds - Equity
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Maximum | Equity Funds
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					85.00%		85.00%
Maximum | North Country Funds - Fixed Income
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Maximum | Other Mutual Funds - Fixed Income
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage
Maximum | Fixed Income Funds
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Target Allocation Maximum, Percentage					30.00%		30.00%
Subsequent to January 1, 2003
Defined Benefit Plan Disclosure [Line Items]
Service credits, percent of eligible salaries		6.00%
Prior to January 1, 2003 | Minimum
Defined Benefit Plan Disclosure [Line Items]
Service credits, percent of eligible salaries		6.00%
Prior to January 1, 2003 | Maximum
Defined Benefit Plan Disclosure [Line Items]
Service credits, percent of eligible salaries		12.00%

[1] Acquisition of Arrow Financial Corporation common stock was under 10% of the total fair value of the employee's pension plan assets at the time of acquisition.

[2] The North Country Funds - Equity and the North Country Funds - Fixed Income are publicly traded mutual funds advised by Arrow's subsidiary, North Country Investment Advisers, Inc.