Investment in Joint Venture Arrangements Investment in Joint Venture Arrangements Income Statement Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Revenue	$ 4,632	$ 10,286	$ 5,995
Costs and expenses	2,748	6,817	5,849
Income (loss)	1,884	3,469	146
Equity in Income (loss) from joint venture arrangements	$ 312	$ 539	$ 477

The amount of net income (loss) reported by an equity method investment of the entity.

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