Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

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The amount of cash paid during the reporting period for charges associated with the mergers.

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Acquisitions Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
Acquisitions Narrative (Details) - USD ($) $ in Thousands	Apr. 29, 2016	Dec. 31, 2017	Dec. 31, 2016
AmCo Holding Company
Business Acquisition [Line Items]
Revenues		$ 134,386
Operating Income (Loss)		12,579
Payments for Merger Related Costs		7,000
Payments to Acquire Businesses, Gross		$ 285,468
Interboro Insurance Company
Business Acquisition [Line Items]
Notes Issued	$ 8,550
Accrued Liabilities	3,471
Revenues			$ 28,573
Operating Income (Loss)			14,202
Payments for Merger Related Costs			224
Payments to Acquire Businesses, Gross	$ 48,450		$ 60,471