Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares
Class A common stock dividends | $ / shares	$ 2.35	$ 3.03	$ 2.81
Tax expense (benefit) related to delivery of Class A Common Stock in connection with share-based incentive compensation | $	$ (4,437)	$ 7,711	$ 5,271
Tax expense (benefit) on delivery of Class A common stock in connection with business acquisitions | $	$ (5)		$ 28
Common stock, shares issued | shares	112,766,091	129,766,091
Class A Common Stock [Member]
Common stock, shares issued | shares	112,766,091	129,766,091	129,766,091