Parent Only Financial Information Parent Only Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
ASSETS
Interest-Bearing Deposits at Banks	$ 12,705	$ 11,756
Available-for-sale Securities	457,606	478,698
Held-to-Maturity Securities	299,261	239,803
Other Assets	43,235	37,236
Total Assets	2,163,698	2,022,796
LIABILITIES
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts	20,000	20,000
Other Liabilities	24,437	24,138
Total Liabilities	1,971,544	1,846,971
STOCKHOLDERS' EQUITY
Total Stockholders' Equity	192,154	175,825	166,385	152,259
Total Liabilities and Stockholders' Equity	2,163,698	2,022,796
Arrow Financial Corporation [Member]
ASSETS
Interest-Bearing Deposits at Banks	3,349	1,913
Available-for-sale Securities	1,166	1,148
Held-to-Maturity Securities	1,000	1,000
Investment in Subsidiaries at Equity	206,680	192,985
Other Assets	5,807	5,339
Total Assets	218,002	202,385
LIABILITIES
Junior Subordinated Obligations Issued to Unconsolidated Subsidiary Trusts	20,000	20,000
Other Liabilities	5,848	6,560
Total Liabilities	25,848	26,560
STOCKHOLDERS' EQUITY
Total Stockholders' Equity	192,154	175,825
Total Liabilities and Stockholders' Equity	$ 218,002	$ 202,385