Investments (OTTI by Asset Type) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
OTTI Losses Gross	$ 43	$ 342	$ 4,729	$ 4,494
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	(30)	0	(36)	10
OTTI Losses Recognized in Earnings	73	342	4,765	4,484
AFS Fixed Income Securities [Member]
OTTI Losses Gross			3,179	1,175
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income			(36)	10
OTTI Losses Recognized in Earnings			3,215	1,165
AFS Fixed Income Securities [Member] \| US Treasury and Government [Member]
OTTI Losses Gross			31
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income			0
OTTI Losses Recognized in Earnings			31
AFS Fixed Income Securities [Member] \| Obligations of States and Political Subdivisions [Member]
OTTI Losses Gross			612
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income			0
OTTI Losses Recognized in Earnings			612
AFS Fixed Income Securities [Member] \| Corporate Securities [Member]
OTTI Losses Gross	12		587	1,077
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0	0
OTTI Losses Recognized in Earnings	12		587	1,077
AFS Fixed Income Securities [Member] \| Collateralized Loan Obligations and Other Asset Backed Securities [Member]
OTTI Losses Gross	11		96
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	11		96
AFS Fixed Income Securities [Member] \| Commercial Mortgage Backed Securities [Member]
OTTI Losses Gross			670
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income			0
OTTI Losses Recognized in Earnings			670
AFS Fixed Income Securities [Member] \| Residential Mortgage Backed Securities [Member]
OTTI Losses Gross	20		1,183	98
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	(30)		(36)	10
OTTI Losses Recognized in Earnings	$ 50		1,219	88
Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross		342	1,360	3,319
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income		0	0	0
OTTI Losses Recognized in Earnings		342	1,360	3,319
Other Investments [Member]
OTTI Losses Gross			190
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income			0
OTTI Losses Recognized in Earnings			190
Common Stock [Member] \| Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross		342	1,360	3,316
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income		0	0	0
OTTI Losses Recognized in Earnings		$ 342	$ 1,360	3,316
Preferred Stock [Member] \| Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross				3
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income				0
OTTI Losses Recognized in Earnings				$ 3

Income Statement line item amount before tax of other than temporary impairment loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

No definition available.

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e25351-111560

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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