Goodwill, Core Deposit Intangibles and Other Intangible Assets (Changes in Capitalized Mortgage and Commercial Servicing Rights) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Servicing Asset at Fair Value, Amount [Roll Forward]
Valuation allowance on servicing rights	$ (46)	$ 21	$ (33)
Mortgage Servicing Rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	23,248	32,088
Originations	5,045	7,149
Amortization	(5,867)	(9,049)
Sale of mortgage servicing rights	0	(6,940)
Acquired mortgage servicing rights	6,995	0
Valuation allowance on servicing rights	(58)	0
Balance at end of period	29,363	23,248	32,088
Fair value of mortgage servicing rights	$ 48,680	$ 37,081
Servicing rights, net to servicing portfolio (as a percent)	0.72%	0.65%
Commercial Servicing Rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	$ 2,609	$ 3,690
Originations	115	209
Amortization	(1,027)	(1,311)
Acquired mortgage servicing rights	0	0
Valuation allowance on servicing rights	12	21
Balance at end of period	1,709	2,609	$ 3,690
Fair value of mortgage servicing rights	$ 2,134	$ 3,221
Servicing rights, net to servicing portfolio (as a percent)	1.59%	1.87%

Commercial Servicing Rights (CSR) Impairment (Recovery)

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- Definition

Servicing Asset, Net to Servicing Portfolio, Percentage

+ References

No definition available.

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- Definition

The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(6)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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- Definition

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
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-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

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- Definition

Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

Amount conveyed to unrelated parties of contract to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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