Investments - Summarized Financial Information (Details) - WMES - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Income Statement [Abstract]
Revenue	$ 8,111	$ 9,543
Expenses	7,754	8,372
WMES net income	357	$ 1,171
Statement of Financial Position [Abstract]
Total assets	331,526		$ 322,606
Total liabilities	235,615		227,052
Total WMES net equity	$ 95,911		$ 95,554

The amount of assets reported by an equity method investment of the entity.

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Amount of equity, including noncontrolling interest, reported by an equity method investment of the entity.

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The amount of liabilities reported by an equity method investment of the entity.

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