Equity-Based Compensation - Stock Options (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Stock options
Outstanding at the beginning of the period (in shares)	467,633
Options expired (in shares)	(13,172)
Outstanding at the end of the period (in shares)	454,461	467,633
Vested or expected to vest (in shares)	454,461
Exercisable (in shares)	454,461
Weighted average exercise price
Outstanding at the beginning of the period (in dollars per share)	$ 50.64
Options expired (in dollars per share)	51.50
Outstanding at the end of the period (in dollars per share)	50.61	$ 50.64
Vested or expected to vest (in dollars per share)	50.61
Exercisable (in dollars per share)	$ 50.61
Weighted average remaining contractual life
Outstanding	4 years 4 months 6 days	5 years 18 days
Vested or expected to vest	4 years 4 months 6 days
Exercisable	4 years 4 months 6 days
Additional disclosures
Unamortized equity based compensation expense	$ 0