Investments (OTTI by Asset Type) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
OTTI Losses Gross	$ 1,211	$ 559	$ 4,686	$ 4,152
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	(6)	10	(6)	10
OTTI Losses Recognized in Earnings	1,217	549	4,692	4,142
US Treasury and Government [Member]
OTTI Losses Gross	2		31
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	2		31
Obligations of States and Political Subdivisions [Member]
OTTI Losses Gross	239		612
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	239		612
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
OTTI Losses Gross	62		85
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	62		85
Commercial Mortgage Backed Securities [Member]
OTTI Losses Gross	220		670
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	220		670
Other Investments [Member]
OTTI Losses Gross	190		190
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	190		190
AFS Fixed Income Securities [Member]
OTTI Losses Gross	975	202	3,136	1,175
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	(6)	10	(6)	10
OTTI Losses Recognized in Earnings	981	192	3,142	1,165
AFS Fixed Income Securities [Member] \| Corporate Securities [Member]
OTTI Losses Gross	381	104	575	1,077
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0	0	0
OTTI Losses Recognized in Earnings	381	104	575	1,077
AFS Fixed Income Securities [Member] \| Residential Mortgage Backed Securities [Member]
OTTI Losses Gross	71	98	1,163	98
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	(6)	10	(6)	10
OTTI Losses Recognized in Earnings	77	88	1,169	88
Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross	46	357	1,360	2,977
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0	0	0
OTTI Losses Recognized in Earnings	46	357	1,360	2,977
Common Stock [Member] \| Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross	46	357	1,360	2,974
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0	0	0
OTTI Losses Recognized in Earnings	$ 46	$ 357	$ 1,360	2,974
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=66902209&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=27723805&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=73527792&loc=SL6284393-111563

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