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

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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The cash outflow to reacquire common stock during the period.

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Cash inflow received as distributions, returns of capital, or sale proceeds from partnership interests held for investment purposes.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended
	May 07, 2019	Apr. 30, 2019	May 08, 2019	Mar. 31, 2019	Mar. 31, 2018
Subsequent Event [Abstract]
Amount withdrawn from partnership				$ 17,214	$ 0
Repurchase of common shares amount paid			$ 3,031	$ 468	$ 235
Arbiter Partners Limited [Member]
Subsequent Event [Abstract]
Amount withdrawn from partnership		$ 3,000
Class A [Member]
Subsequent Event [Abstract]
Repurchase of common stock (in shares)				100
Class B [Member]
Subsequent Event [Abstract]
Repurchase of common stock (in shares)				24,858
Subsequent Event [Member]
Subsequent Event [Abstract]
Dividend payable, date declared	May 07, 2019
Dividend payable, date to be paid	Jun. 04, 2019
Dividend payable, date of record	May 21, 2019
Subsequent Event [Member] \| Class A [Member]
Subsequent Event [Abstract]
Dividend payable (in dollars per share)	$ 0.10
Repurchase of common stock (in shares)			23
Subsequent Event [Member] \| Class B [Member]
Subsequent Event [Abstract]
Dividend payable (in dollars per share)	$ 0.10
Repurchase of common stock (in shares)			172,416