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 YYYY-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=123431023&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=120397183&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 YYYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in YYYY-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
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-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

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Dividends (Details) - USD ($)							3 Months Ended		9 Months Ended
Dividends (Details) - USD ($)	Sep. 28, 2021	Jun. 18, 2021	Apr. 10, 2020	Mar. 16, 2020	Mar. 04, 2020	Apr. 10, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Common Stock, Dividends, Per Share, Declared							$ 0.16	$ 0	$ 0.32	$ 0.32
Dividends Payable, Date to be Paid	Oct. 22, 2021	Jul. 16, 2021				Apr. 10, 2020
Dividends Payable, Date of Record	Oct. 08, 2021	Jun. 30, 2020		Mar. 16, 2020
Dividends	$ 960,000	$ 960,000	$ 1,900,000
Payments of Ordinary Dividends, Common Stock									$ 956,000	$ 3,716,000
Dividends Payable, Date Declared	Sep. 28, 2021	Jun. 18, 2021			Mar. 04, 2020
Class A Common Stock
Common Stock, Dividends, Per Share, Declared	$ 0.16	$ 0.16			$ 0.32
Class B Common Stock
Common Stock, Dividends, Per Share, Declared	$ 0.16	$ 0.16			$ 0.32