Fair Value Measurement (Level 3 Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	$ 22,875	$ 28,328
Included in earnings, as a part of:
Included in other comprehensive income	(393)	719
Purchases	5,196	8,201
Sales	(5,896)	(3,618)
Transfers in	6,640	2,424
Transfers out	(12,570)	(13,138)
Ending Balance	15,257	22,875
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0
U.S. Government-sponsored enterprise obligations [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	0	0
Included in earnings, as a part of:
Included in other comprehensive income	0	1
Purchases	0	1,000
Sales	0	0
Transfers in	0	0
Transfers out	0	(1,001)
Ending Balance		0
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0
State and municipal bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	5,025	7,338
Included in earnings, as a part of:
Included in other comprehensive income	(459)	(29)
Purchases	0	1,861
Sales	0	(1,731)
Transfers in	0	2,119
Transfers out	(4,566)	(4,424)
Ending Balance		5,025
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0
Corporate debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	13,081	14,176
Included in earnings, as a part of:
Included in other comprehensive income	73	688
Purchases	1,996	2,000
Sales	(1,896)	(1,826)
Transfers in	6,640	0
Transfers out	(5,049)	(2,025)
Ending Balance	14,500	13,081
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0
Asset-backed securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	4,769	6,814
Included in earnings, as a part of:
Included in other comprehensive income	(7)	59
Purchases	1,500	3,340
Sales	(4,000)	(61)
Transfers in	0	305
Transfers out	(1,494)	(5,688)
Ending Balance	757	4,769
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0
Equity Securities and Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	0	0
Included in earnings, as a part of:
Included in other comprehensive income	0	0
Purchases	1,700	0
Sales	0	0
Transfers in	0	0
Transfers out	(1,461)	0
Ending Balance		0
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0
Net investment income [Member]
Included in earnings, as a part of:
Net investment income	18	51
Net investment income [Member] \| U.S. Government-sponsored enterprise obligations [Member]
Included in earnings, as a part of:
Net investment income	0	0
Net investment income [Member] \| State and municipal bonds [Member]
Included in earnings, as a part of:
Net investment income	0	(14)
Net investment income [Member] \| Corporate debt [Member]
Included in earnings, as a part of:
Net investment income	18	65
Net investment income [Member] \| Asset-backed securities [Member]
Included in earnings, as a part of:
Net investment income	0	0
Net investment income [Member] \| Equity Securities and Other [Member]
Included in earnings, as a part of:
Net investment income	0	0
Equity in earnings of unconsolidated subsidiaries [Member]
Included in earnings, as a part of:
Net investment income	(83)	0
Equity in earnings of unconsolidated subsidiaries [Member] \| U.S. Government-sponsored enterprise obligations [Member]
Included in earnings, as a part of:
Net investment income	0	0
Equity in earnings of unconsolidated subsidiaries [Member] \| State and municipal bonds [Member]
Included in earnings, as a part of:
Net investment income	0	0
Equity in earnings of unconsolidated subsidiaries [Member] \| Corporate debt [Member]
Included in earnings, as a part of:
Net investment income	0	0
Equity in earnings of unconsolidated subsidiaries [Member] \| Asset-backed securities [Member]
Included in earnings, as a part of:
Net investment income	0	0
Equity in earnings of unconsolidated subsidiaries [Member] \| Equity Securities and Other [Member]
Included in earnings, as a part of:
Net investment income	(83)	0
Net realized investment gains (losses) [Member]
Included in earnings, as a part of:
Net investment income	(530)	(92)
Net realized investment gains (losses) [Member] \| U.S. Government-sponsored enterprise obligations [Member]
Included in earnings, as a part of:
Net investment income	0	0
Net realized investment gains (losses) [Member] \| State and municipal bonds [Member]
Included in earnings, as a part of:
Net investment income	0	(95)
Net realized investment gains (losses) [Member] \| Corporate debt [Member]
Included in earnings, as a part of:
Net investment income	(363)	3
Net realized investment gains (losses) [Member] \| Asset-backed securities [Member]
Included in earnings, as a part of:
Net investment income	(11)	0
Net realized investment gains (losses) [Member] \| Equity Securities and Other [Member]
Included in earnings, as a part of:
Net investment income	$ (156)	$ 0

Included in Earnings, as a part of.

No definition available.

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- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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