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Dividends (Narrative) (Details) - $ / shares |  |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | --- | ---
Apr. 15, 2021 | Jan. 14, 2021 | Oct. 15, 2020 | Jun. 26, 2021 | Jun. 27, 2020 | Jun. 26, 2021 | Jun. 27, 2020
Class A Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock |  |  |  | $ 0.165 | $ 0.165 | $ 0.495 | $ 0.495
Class B Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock |  |  |  | $ 0.150 | $ 0.150 | $ 0.450 | $ 0.450
Dividend I [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Dividend payment date |  |  |  |  |  | Oct. 15, 2020 |
Dividend record date |  |  |  |  |  | Oct. 08, 2020 |
Dividend I [Member] | Class A Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock |  |  | $ 0.165 |  |  |  |
Dividend I [Member] | Class B Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock |  |  | $ 0.15 |  |  |  |
Dividend II [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Dividend payment date |  |  |  |  |  | Jan. 14, 2021 |
Dividend record date |  |  |  |  |  | Jan. 07, 2021 |
Dividend II [Member] | Class A Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock |  | $ 0.165 |  |  |  |  |
Dividend II [Member] | Class B Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock |  | $ 0.15 |  |  |  |  |
Dividend III [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Dividend payment date |  |  |  |  |  | Apr. 15, 2021 |
Dividend record date |  |  |  |  |  | Apr. 08, 2021 |
Dividend III [Member] | Class A Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock | $ 0.165 |  |  |  |  |  |
Dividend III [Member] | Class B Common Stock [Member] |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Cash dividends per share of common stock | $ 0.15 |  |  |  |  |  |

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- Definition 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=121583591&loc=d3e4304-108586 + Details
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