Equity Investees (Schedule of Operations for Equity Investees) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
INCOME STATEMENT DATA:
Revenues	$ 30,602	$ 27,768	$ 96,041	$ 83,962
Operating income	21,745	17,772	69,705	57,444
Net income	$ 19,431	$ 15,721	$ 62,576	$ 51,731

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

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