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Earnings Per Share and Dividends - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Feb. 17, 2021
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Dividends Payable [Line Items]                                
Dividends to Class A common stockholders                           $ 16,044 $ 14,970 $ 14,194
Common Class A                                
Dividends Payable [Line Items]                                
Cash dividends declared per share of Class A common stock                           $ 0.88 $ 0.84 $ 0.80
Quarterly dividend | Common Class A                                
Dividends Payable [Line Items]                                
Cash dividends declared per share of Class A common stock   $ 0.22 $ 0.22 $ 0.22 $ 0.22 $ 0.21 $ 0.21 $ 0.21 $ 0.21 $ 0.20 $ 0.20 $ 0.20 $ 0.20 $ 0.88 $ 0.84 $ 0.80
Quarterly dividend | Common Class A | Subsequent Event                                
Dividends Payable [Line Items]                                
Cash dividends declared per share of Class A common stock $ 0.23