Intangibles - Amortizable Intangible Assets Other Than Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Noncompetition agreements	$ 103,510	$ 107,726
Indefinite-lived licenses	90,209	59,885
Other	23,887	31,801
Intangible assets, gross (excluding goodwill)	217,606	199,412
Less accumulated amortization	(81,922)	(80,566)
Total intangible assets	$ 135,684	$ 118,846