Segment Information (Equity in (earnings) loss of unconsolidated entities) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity in (earnings) loss of unconsolidated entities:
Equity in earnings of unconsolidated entities	$ (747)	$ (2,690)	$ 1,985

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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