General (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Potentially dilutive securities (in shares)	82,000	0	73,000	0
Deferred policy acquisition cost amortization	$ 142,295	$ 136,290	$ 424,799	$ 416,728
Advertising expenses			34,000	32,000
Revenue from contract with customer			12,300	11,600	$ 15,200
Related expenses from contracts with customers			$ 7,600	$ 7,800	$ 10,200
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, percentage of revenue			0.50%	0.50%	0.40%
Commission income receivable	1,100		$ 1,100		$ 1,200
Refund liability	$ 700		$ 700		$ 700
Insurance Policies [Member] \| Auto Insurance Specialists LLC and Poliseek AIS Insurance Solutions Inc
Disaggregation of Revenue [Line Items]
Revenue from contract with customer, percentage of revenue			80.00%

Revenue from Contract with Customer, Percentage of Revenue

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For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Amount of amortization expense (reversal of expense) for deferred policy acquisition costs.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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