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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands																				1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 16, 2020	Mar. 04, 2020	Mar. 04, 2020	Jan. 17, 2020	Dec. 27, 2019	Dec. 11, 2019	Dec. 11, 2019	Oct. 11, 2019	Sep. 23, 2019	Sep. 12, 2019	Sep. 12, 2019	Jul. 05, 2019	Jun. 14, 2019	May 30, 2019	Apr. 10, 2019	Mar. 29, 2019	Mar. 12, 2019	Mar. 04, 2019	Feb. 26, 2019	May 30, 2019	Feb. 26, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Common Stock, Dividends, Per Share, Declared																						$ 0	$ 0.30	$ 0.32	$ 0.60
Dividends Payable, Date to be Paid	Mar. 16, 2020			Jan. 17, 2020				Oct. 11, 2019				Jul. 05, 2019			Apr. 10, 2020	Mar. 29, 2019
Dividends Payable, Date of Record					Dec. 27, 2019				Sep. 23, 2019				Jun. 14, 2019				Mar. 12, 2019
Dividends		$ 1,900				$ 1,800				$ 1,800										$ 1,800	$ 1,800
Payments of Ordinary Dividends, Common Stock																								$ 3,716	$ 5,058
Dividends Payable, Date Declared			Mar. 04, 2020				Dec. 11, 2019				Sep. 12, 2019			May 30, 2019					Feb. 26, 2019
Class A Common Stock
Common Stock, Dividends, Per Share, Declared						$ 0.30				$ 0.30								$ 0.32		$ 0.30	$ 0.30
Class B Common Stock
Common Stock, Dividends, Per Share, Declared		$ 0.32				$ 0.30				$ 0.30										$ 0.30	$ 0.30