Goodwill and Core Deposit and Trust Relationship Intangibles (Changes in Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Goodwill [Line Items]
Beginning balance	$ 41,730	$ 41,780
2011 impairment charge		(50)
2012 activity	5,906
Ending balance	47,636	41,730
Banking
Goodwill [Line Items]
Beginning balance	34,720	34,720
2011 impairment charge
2012 activity	6,182
Ending balance	40,902	34,720
Financial Services
Goodwill [Line Items]
Beginning balance	7,010	7,060
2011 impairment charge		(50)
2012 activity	(276)
Ending balance	$ 6,734	$ 7,010

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

- Definition

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

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+ Details

- Definition

Change in the carrying value of goodwill. The change could be the result of new goodwill acquired, goodwill impairment, if any, goodwill written off related to the sale of a business or other adjustments to goodwill.

+ References+ Details