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Summary Of Significant Accounting Policies (Summary Of Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary Of Significant Accounting Policies [Abstract]
Interest expense	$ 14,850	$ 11,823	$ 9,323
Income taxes	13,187	10,555	7,494
Real estate and other assets acquired in settlement of loans	426	496	374
Accrued and declared unpaid dividends	3,859	3,403	3,185
Increase (decrease) in net unsettled security purchases		(170)	(478)
Securities transferred from available for sale to held to maturity			$ 165,238
Common stock issued for acquisition		8,100
Loans and other non-cash assets, excluding goodwill and other intangible asses	812	4,848
Deposits and other liabilities	$ 44	$ 1,845

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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