Investments in Qualified Affordable Housing Projects - Components of Qualified Affordable Housing Projects Included in Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Tax credit amortization	$ 394	$ 394	$ 1,181	$ 1,198
Tax credits and other benefits	(529)	(572)	(1,674)	(1,717)
Total	$ (135)	$ (178)	$ (493)	$ (519)

Affordable Housing Tax Credits and Other Benefits, Net of Amortization

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- Definition

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

+ References

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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- Definition

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

+ References

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 (c)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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