Investments (OTTI by Asset Type) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
OTTI Losses Gross	$ 3,475	$ 3,593
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0
OTTI Losses Recognized in Earnings	3,475	3,593
US Treasury and Government [Member]
OTTI Losses Gross	29
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0
OTTI Losses Recognized in Earnings	29
Obligations of States and Political Subdivisions [Member]
OTTI Losses Gross	373
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0
OTTI Losses Recognized in Earnings	373
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
OTTI Losses Gross	23
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0
OTTI Losses Recognized in Earnings	23
Commercial Mortgage Backed Securities [Member]
OTTI Losses Gross	450
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0
OTTI Losses Recognized in Earnings	450
AFS Fixed Income Securities [Member]
OTTI Losses Gross	2,161	973
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0
OTTI Losses Recognized in Earnings	2,161	973
AFS Fixed Income Securities [Member] \| Corporate Securities [Member]
OTTI Losses Gross	194	973
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0
OTTI Losses Recognized in Earnings	194	973
AFS Fixed Income Securities [Member] \| Residential Mortgage Backed Securities [Member]
OTTI Losses Gross	1,092
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0
OTTI Losses Recognized in Earnings	1,092
Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross	1,314	2,620
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0
OTTI Losses Recognized in Earnings	1,314	2,620
Common Stock [Member] \| Total AFS Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross	1,314	2,617
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0
OTTI Losses Recognized in Earnings	$ 1,314	2,617
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

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.

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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Amount before tax of other than temporary impairment (OTTI) loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25362-111560

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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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