Investments (OTTI by Asset Type) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
OTTI Losses Gross	$ 6,579	$ 4,809	$ 8,509
OTTI included in OCI	0	(36)	10
Total OTTI charges recognized in earnings	6,579	4,845	8,499
Other Investments [Member]
OTTI Losses Gross	1,893	190
OTTI included in OCI	0	0
Total OTTI charges recognized in earnings	1,893	190
AFS Fixed Income Securities [Member]
OTTI Losses Gross	4,686	3,184	5,191
OTTI included in OCI	0	(36)	10
Total OTTI charges recognized in earnings	4,686	3,220	5,181
AFS Fixed Income Securities [Member] \| US Government Agencies Debt Securities [Member]
OTTI Losses Gross		36
OTTI included in OCI		0
Total OTTI charges recognized in earnings		36
AFS Fixed Income Securities [Member] \| Obligations of States and Political Subdivisions [Member]
OTTI Losses Gross		612	2,797
OTTI included in OCI		0	0
Total OTTI charges recognized in earnings		612	2,797
AFS Fixed Income Securities [Member] \| Corporate Securities [Member]
OTTI Losses Gross	1,783	587	1,880
OTTI included in OCI	0	0	0
Total OTTI charges recognized in earnings	1,783	587	1,880
AFS Fixed Income Securities [Member] \| Collateralized Loan Obligations and Other Asset-Backed Securities [Member]
OTTI Losses Gross		96	19
OTTI included in OCI		0	0
Total OTTI charges recognized in earnings		96	19
AFS Fixed Income Securities [Member] \| Commercial Mortgage Backed Securities [Member]
OTTI Losses Gross		670	220
OTTI included in OCI		0	0
Total OTTI charges recognized in earnings		670	220
AFS Fixed Income Securities [Member] \| Residential Mortgage Backed Securities [Member]
OTTI Losses Gross	2,903	1,183	275
OTTI included in OCI	0	(36)	10
Total OTTI charges recognized in earnings	$ 2,903	1,219	265
Available-for-sale Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross		1,435	3,318
OTTI included in OCI		0	0
Total OTTI charges recognized in earnings		1,435	3,318
Common Stock [Member] \| Available-for-sale Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross		1,435	3,316
OTTI included in OCI		0	0
Total OTTI charges recognized in earnings		$ 1,435	3,316
Nonredeemable Preferred Stock [Member] \| Available-for-sale Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross			2
OTTI included in OCI			0
Total OTTI charges recognized in earnings			$ 2

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=115930623&loc=d3e25362-111560

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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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

No definition available.

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