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Qualified Affordable Housing And Historic Rehabilitation Projects (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Investments in Affordable Housing Projects [Abstract]
Investment in qualified affordable housing projects	$ 4,600,000		$ 4,600,000		$ 6,000,000.0
Amortization expense included in noninterest expense	700,000	$ 700,000	1,400,000	$ 1,400,000
Affordable housing tax credits	700,000	$ 800,000	1,500,000	$ 1,500,000
Investment in historic rehabilitation projects	300,000		300,000		300,000
Historic rehabilitation tax credits	$ 200,000		$ 500,000		$ 0

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Amortization Method Historic Rehabilitation Project Investments

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Historic Rehabilitation Tax Credits And Other Tax Benefits, Amount

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Amount of affordable housing tax credits and other tax benefits recognized.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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Amount of investment in qualified affordable housing projects.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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Amount of amortization expense of investment in qualified affordable housing projects.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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