Acquisition and Discontinued Operations Summary financial information for Mendota and ARS included in income (loss) from discontinued operations, net of taxes in the consolidated statements of operations (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	$ 19,159		$ 36,889		$ 76,033	$ 109,344
Net Investment Income	629		1,133		2,277	3,165
Net realized losses	(414)		0		(17)	(1)
Gain on change in fair value of equity investments	337		0		1,081	0
Disposal Group, Including Discontinued Operation, Other Income	2,184		2,467		7,060	7,494
Loss and loss adjustment expenses					1,628
Disposal Group, Including Discontinued Operation, Other Expense	713		5,128		7,101	15,764
Disposal Group, Including Discontinued Operation, General and Administrative Expense	3,925		4,400		11,703	14,830
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	0		0		0	250
Disposal Group, Including Discontinued Operation, Operating Expense	18,742		37,260		74,636	109,897
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	417		(371)		1,397	(553)
Discontinued Operation, Tax Effect of Discontinued Operation	0		0		0	(85)
Income (loss) from discontinued operations, net of taxes	417		(371)		1,397	(468)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	(1,172)		0		(7,800)	1,017
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation	0		0		0	0
(Loss) gain on disposal of discontinued operations, net of taxes	(1,172)		0		(7,800)	1,017
Operating Income (Loss) [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	16,727		32,556		68,319	98,996
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Investment Income	240		(110)		674	(255)
Net realized losses	130		1,976		(4)	3,109
Gain on change in fair value of equity investments	(122)		0		(16)	0
Loss and loss adjustment expenses	14,104		27,732		55,832	79,053
(Loss) gain on disposal of discontinued operations, net of taxes		$ 1,335		$ 1,017
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) gain on disposal of discontinued operations, net of taxes	$ (755)		$ (371)		$ (6,403)	$ 549