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Stockholders' Equity - Dividends Declared (Details) - $ / shares | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Dividends Declared [Line Items] |  |  |  |
Dividends declared per Class A common share (in dollars per share) | $ 0.67 | $ 0.60 | $ 2.56 | $ 2.74
Quarterly |  |  |  |
Dividends Declared [Line Items] |  |  |  |
Dividends declared per Class A common share (in dollars per share) | 0.67 | 0.60 | 1.96 | 1.71
Special Annual |  |  |  |
Dividends Declared [Line Items] |  |  |  |
Dividends declared per Class A common share (in dollars per share) | $ 0 | $ 0 | $ 0.60 | $ 1.03

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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + 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 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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