Principal Business Activity and Significant Accounting Policies - Non-controlling interest (Details)	Dec. 31, 2019	Dec. 31, 2018
Continuing LLC Owners
Noncontrolling Interest [Line Items]
Interest held by non-controlling owners	16.80%	23.20%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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