The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Amortization of other intangible assets	$ 4,789,000	$ 4,621,000	$ 4,692,000
Community banking
Goodwill [Line Items]
Goodwill increase	26,200,000
Specialty finance
Goodwill [Line Items]
Goodwill increase	$ 657,000
Core deposit intangibles \| Community banking
Goodwill [Line Items]
Finite-lived intangibles, useful life	10 years
Customer list intangibles \| Specialty finance
Goodwill [Line Items]
Finite-lived intangibles, useful life	18 years
Customer list intangibles \| Wealth management
Goodwill [Line Items]
Finite-lived intangibles, useful life	10 years