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Investments Investments (Equity in Earnings (Loss) of Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Losses recorded from affordable housing projects	$ 5,612	$ 3,964	$ 9,712	$ 7,272
Tax credits recognized related to affordable housing projects	4,624	4,612	9,237	9,225
Losses from historic tax credit investments	1,506	2,350	3,382	2,766
Tax credits recognized related to historic tax credit investments	$ 693	$ 820	$ 1,355	$ 2,624

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- Definition

Historic Tax Credits Investments and Other Tax Benefits, Amount

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- Definition

Income (Loss) from Historical Projects, Equity Method Investments

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985

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Amount of investment income (loss) of qualified affordable housing project investments accounted for using the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985

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