Consolidated Statement of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash Flows from Operating Activities:
Net Income	$ 22,179	$ 21,933	$ 21,892
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Provision for Loan Losses	845	845	1,302
Depreciation and Amortization	8,856	6,509	3,563
Allocation of ESOP Stock	409	428	453
Gains on the Sale of Securities Available-for-Sale	(949)	(2,795)	(1,507)
Losses on the Sale of Securities Available-for-Sale	84	0	0
Loans Originated and Held-for-Sale	(60,668)	(39,111)	(41,030)
Proceeds from the Sale of Loans Held-for-Sale	61,041	49,378	31,760
Net Gains on the Sale of Loans	(2,282)	(866)	(1,024)
Net Loss (Gains) on the Sale of Premises and Equipment, Other Real Estate Owned and Repossessed Assets	(71)	(32)	10
Contributions to Pension Plans	(328)	(5,319)	(1,813)
Deferred Income Tax Expense (Benefit) Expense	(353)	2,172	154
Shares Issued Under the Directors' Stock Plan	175	175	149
Stock-Based Compensation Expense	424	354	299
Net Decrease in Other Assets	(2,108)	(1,725)	(638)
Net Increase (Decrease) in Other Liabilities	990	689	(4,627)
Net Cash Provided By Operating Activities	32,460	36,085	10,219
Cash Flows from Investing Activities:
Proceeds from the Sale of Securities Available-for-Sale	58,718	39,009	25,497
Proceeds from the Maturities and Calls of Securities Available-for-Sale	210,224	280,126	278,804
Purchases of Securities Available-for-Sale	(197,029)	(354,310)	(382,614)
Proceeds from the Maturities and Calls of Securities Held-to-Maturity	49,983	40,692	15,227
Purchases of Securities Held-to-Maturity	(140,635)	(31,701)	(6,532)
Net (Increase) Decrease in Loans	(40,951)	3,108	(24,259)
Proceeds from the Sales of Premises and Equipment, Other Real Estate Owned and Repossessed Assets	1,263	770	612
Purchases of Premises and Equipment	(8,073)	(5,372)	(1,081)
Cash Paid for Subsidiaries	(75)	(3,296)	264
Net Decrease in Other Investments	(930)	(1,880)	(333)
Purchase of Bank Owned Life Insurance	0	(15,702)	0
Net Cash Used In Investing Activities	(65,645)	(44,796)	(93,749)
Cash Flows from Financing Activities:
Net Increase in Deposits	87,109	110,042	90,438
Net (Decrease) Increase in Short-Term Borrowings	(26,615)	15,079	(20,694)
Federal Home Loan Bank Advances	0	10,000	10,000
Federal Home Loan Bank Repayments	(10,000)	(100,000)	(20,000)
Purchases of Treasury Stock	(4,877)	(6,039)	(3,347)
Stock Options Exercised	2,105	1,413	798
Shares Issued Under the Employee Stock Purchase Plan	484	474	475
Tax Benefit from Exercise of Stock Options	68	51	105
Shares Issued for Dividend Reinvestment Plans	1,822	1,796	1,715
Acquisition by ESOP of Arrow Stock	0	0	(1,000)
Cash Dividends Paid	(11,815)	(11,448)	(10,997)
Net Cash Provided By Financing Activities	38,281	21,368	47,493
Net Increase (Decrease) in Cash and Cash Equivalents	5,096	12,657	(36,037)
Cash and Cash Equivalents at Beginning of Year	43,736	31,079	67,116
Cash and Cash Equivalents at End of Year	48,832	43,736	31,079
Supplemental Disclosures to Statements of Cash Flow Information:
Interest on Deposits and Borrowings	12,520	19,490	23,995
Income Taxes	8,866	7,952	15,223
Non-cash Investing and Financing Activities:
Transfer of Loans to Other Real Estate Owned and Repossessed Assets	1,426	1,011	568
Shares Issued for Acquisition of Subsidiary	233	5,261	682
Fair Value of Assets from Acquisition of Subsidiary	0	10,638	882
Fair Value of Liabilities from Acquisition of Subsidiary	$ 0	$ 2,081	$ 465