Consolidated Statement of Cash Flows (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash Flows from Operating Activities:
Net Income	$ 16,502	$ 16,704
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Provision for Loan Losses	565	1,125
Depreciation and Amortization	4,600	2,566
Allocation of ESOP Stock	428	443
Gains on the Sale of Securities Available-for-Sale	(2,795)	(1,496)
Other Than Temporary Impairment	17	0
Loans Originated and Held-for-Sale	(25,939)	(15,041)
Proceeds from the Sale of Loans Held-for-Sale	36,133	15,568
Net (Gains) Losses on the Sale of Loans	(437)	(527)
Net (Gains) Losses on the Sale of Premises and Equipment, Other Real Estate Owned and Repossessed Assets	(9)	1
Contributions to Pension Plans	(1,739)	(239)
Deferred Income Tax Expense (Benefit)	508	(654)
Shares Issued Under the Directors' Stock Plan	88	74
Stock-Based Compensation Expense	266	226
Net (Increase) Decrease in Other Assets	(1,202)	(561)
Net Increase (Decrease) in Other Liabilities	4,614	(2,497)
Net Cash Provided By (Used In) Operating Activities	31,600	15,692
Cash Flows from Investing Activities:
Proceeds from the Sale of Securities Available-for-Sale	38,856	25,440
Proceeds from the Maturities and Calls of Securities Available-for-Sale	236,332	192,092
Purchases of Securities Available-for-Sale	(224,577)	(241,376)
Proceeds from the Maturities and Calls of Securities Held-to-Maturity	24,787	13,898
Purchases of Securities Held-to-Maturity	(11,473)	(3,300)
Net (Increase) Decrease in Loans	14,098	(43,436)
Proceeds from the Sales of Premises and Equipment, Other Real Estate Owned and Repossessed Assets	373	479
Purchases of Premises and Equipment	(2,931)	(1,095)
Acquisition of Subsidiary	(3,297)	264
Purchase of Bank-Owned Life Insurance	(12,833)	0
Net Decrease (Increase) in Other Investments	3,842	(539)
Net Cash Provided By (Used In) Investing Activities	63,177	(57,573)
Cash Flows from Financing Activities:
Net Increase (Decrease) in Deposits	115,335	103,029
Net Increase (Decrease) in Short-Term Borrowings	(3,547)	(4,730)
Proceeds from Federal Home Loan Bank Advances	10,000	10,000
Repayment of Federal Home Loan Bank Advances	(100,000)	0
Purchases of Treasury Stock	(3,892)	(2,595)
Stock Options Exercised	853	319
Shares Issued Under the Employee Stock Purchase Plan	348	341
Tax Benefit from Exercise of Stock Options	21	67
Treasury Shares Issued for Dividend Reinvestment Plans	1,329	1,266
Acquisition by ESOP of Arrow Stock	0	(1,000)
Cash Dividends Paid	(8,513)	(8,202)
Net Cash Provided By (Used In) Financing Activities	11,934	98,495
Net Increase (Decrease) in Cash and Cash Equivalents	106,711	56,614
Cash and Cash Equivalents at Beginning of Period	31,079	67,116
Cash and Cash Equivalents at End of Period	137,790	123,730
Supplemental Disclosures to Statements of Cash Flow Information:
Interest on Deposits and Borrowings	15,379	17,910
Income Taxes	5,652	12,763
Non-cash Investing and Financing Activities:
Transfer of Loans to Other Real Estate Owned and Repossessed Assets	628	400
Net Unrealized Securities Holding Gains Arising During the Period, Net of Tax	4,900	4,841
Reclassification Adjustment for Net Securities Gains Included in Net Income, Net of Tax	(1,688)	(903)
Shares Issued for Acquisition of Subsidiary	5,317	682
Amortization of Net Retirement Plan Actuarial Loss	464	456
Accretion of Net Retirement Plan Prior Service Credit	(58)	(80)
Fair Value of Assets from Acquisition of Subsidiary	10,728	882
Fair Value of Liabilities from Acquisition of Subsidiary	$ 2,114	$ 465