Goodwill and Other Intangible Assets (Schedule of Changes in Carrying Amount of Goodwill and Net Other Intangible Assets) (Details) (USD $)	3 Months Ended	6 Months Ended			6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011 Goodwill [Member]	Dec. 31, 2010 Goodwill [Member]	Jun. 30, 2011 Core Deposit Premium [Member]	Jun. 30, 2011 Mortgage Servicing Rights [Member]
Balance, beginning					$ 125,585,000	$ 125,585,000	$ 9,612,000	$ 1,325,000
Originations								10,000
Amortization	(751,000)	(911,000)	(1,600,000)	(1,800,000)			(1,413,000)	(151,000)
Impairment reversal								11,000
Balance, ending					$ 125,585,000	$ 125,585,000	$ 8,199,000	$ 1,195,000

Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions and the sum of the carrying amounts of all intangible assets, net of accumulated amortization and impairment charges.

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- Definition

The amount of impairment loss or impairment reversal recognized in the period resulting from the write-down or write-up of the carrying amount of a finite-lived intangible asset to fair value.

+ Details

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- Definition

Aggregate amount of amortization expense recognized for intangible asset during the period. A recognized intangible asset shall be amortized over its estimated useful life to the reporting entity unless that life is determined to be indefinite. If an intangible asset has a finite useful life, but the precise length of that life is not known, that intangible asset shall be amortized over the best estimate of its useful life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(2)

+ Details

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- Definition

The increase during the reporting period in the cumulative value of servicing rights. This increase is the result of new servicing rights that are created when mortgages are sold or transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

+ Details

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