Aggregate dividends declared during the period for each share of common stock outstanding.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands					3 Months Ended
	Mar. 16, 2020	Mar. 04, 2020	Mar. 04, 2020	Apr. 10, 2019	Mar. 31, 2021	Mar. 31, 2020
Common Stock, Dividends, Per Share, Declared					$ 0	$ 0.32
Dividends Payable, Date to be Paid	Mar. 16, 2020			Apr. 10, 2020
Dividends			$ 1,900
Payments of Ordinary Dividends, Common Stock						$ 1,797
Dividends Payable, Date Declared		Mar. 04, 2020
Class A Common Stock
Common Stock, Dividends, Per Share, Declared		$ 0.32
Class B Common Stock
Common Stock, Dividends, Per Share, Declared			$ 0.32