Summary of Significant Accounting Policies - Equity Method Investment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2020
Schedule of Equity Method Investments [Line Items]
Loss on equity method investment	$ (1,681)	$ (831)	$ 0
Equity method investment	10,488	8,169
Capital contributed	4,000	9,000	$ 0
WorkLLama, LLC
Schedule of Equity Method Investments [Line Items]
Percent ownership of equity method investment				50.00%
Loss on equity method investment	(1,700)	(800)
Equity method investment	10,500	8,200
Contingent payments liability, maximum	22,500
Capital contributed	$ 4,000	$ 9,000

Equity Method Investment, Contingent Consideration, Range Of Possible Outcome, High

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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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.

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