Investments (OTTI by Asset Type) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
OTTI Losses Gross	$ 3,644	$ 6,579	$ 4,809
OTTI included in OCI	0	0	(36)
Total OTTI charges recognized in earnings	3,644	6,579	4,845
Other Investments [Member]
OTTI Losses Gross	1,049	1,893	190
OTTI included in OCI	0	0	0
Total OTTI charges recognized in earnings	1,049	1,893	190
Available-for-sale Securities [Member]
OTTI Losses Gross	2,595	4,686	3,184
OTTI included in OCI	0	0	(36)
Total OTTI charges recognized in earnings	2,595	4,686	3,220
Available-for-sale Securities [Member] \| US Government Agencies Debt Securities [Member]
OTTI Losses Gross			36
OTTI included in OCI			0
Total OTTI charges recognized in earnings			36
Available-for-sale Securities [Member] \| Obligations of States and Political Subdivisions [Member]
OTTI Losses Gross	66		612
OTTI included in OCI	0		0
Total OTTI charges recognized in earnings	66		612
Available-for-sale Securities [Member] \| Corporate Securities [Member]
OTTI Losses Gross	2,529	1,783	587
OTTI included in OCI	0	0	0
Total OTTI charges recognized in earnings	$ 2,529	1,783	587
Available-for-sale Securities [Member] \| Collateralized Loan Obligations and Other Asset-Backed Securities [Member]
OTTI Losses Gross			96
OTTI included in OCI			0
Total OTTI charges recognized in earnings			96
Available-for-sale Securities [Member] \| Commercial Mortgage Backed Securities [Member]
OTTI Losses Gross			670
OTTI included in OCI			0
Total OTTI charges recognized in earnings			670
Available-for-sale Securities [Member] \| Residential Mortgage Backed Securities [Member]
OTTI Losses Gross		2,903	1,183
OTTI included in OCI		0	(36)
Total OTTI charges recognized in earnings		$ 2,903	1,219
Available-for-sale Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross			1,435
OTTI included in OCI			0
Total OTTI charges recognized in earnings			1,435
Common Stock [Member] \| Available-for-sale Securities [Member] \| Equity Securities [Member]
OTTI Losses Gross			1,435
OTTI included in OCI			0
Total OTTI charges recognized in earnings			$ 1,435

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=118954083&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=118985780&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=118930883&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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