This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The cash inflow associated with the sale of 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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Cash and Cash Equivalents, and Investments - Strategic Investment (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Mar. 31, 2020	Mar. 31, 2017
Schedule of Investments [Line Items]
Gain on sale of strategic equity investments			$ 7,158	$ 0	$ 12,496	$ 0
Proceeds from sale of strategic equity investments					16,076	0
Impairment charge					$ 0	$ 10,000
TAPD, Inc.
Schedule of Investments [Line Items]
Cost method investment								$ 2,000
Consideration received on sale	$ 9,200
Gain on sale of strategic equity investments	7,200
Proceeds from sale of strategic equity investments	$ 9,000
Foreign Entity
Schedule of Investments [Line Items]
Cost method investment									$ 3,000
Consideration received on sale		$ 8,300
Gain on sale of strategic equity investments		5,300
Proceeds from sale of strategic equity investments		$ 7,100
WayUp, Inc.
Schedule of Investments [Line Items]
Impairment charge							$ 10,000