Goodwill and Other Intangibles Investment in West Atlantic (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Interest in Joint Venture	$ 6,400	$ 5,200
Equity Method Investments	12,600		$ 12,500
Goodwill	$ 395,974		$ 390,745

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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