Long-term Equity-based Compensation - Activity Related to Nonvested Restricted Stock (Details)	12 Months Ended
	Dec. 31, 2020 $ / shares shares
Time Vested Restricted Stock Units
Number of Stock Units
Nonvested Balance at Beginning of Year (in shares) | shares	182,188
Grants in Period (in shares) | shares	68,325
Vested in Period (in shares) | shares	(106,807)
Forfeited in Period (in shares) | shares	(11,680)
Nonvested Balance at December 31, 2019 (in shares) | shares	132,026
Weighted- average Grant-date Fair Value Per Unit
Nonvested Balance at Beginning of Year (in dollars per share) | $ / shares	$ 71.12
Granted (in dollars per share) | $ / shares	68.38
Vested (in dollars per share) | $ / shares	68.54
Forfeited (in dollars per share) | $ / shares	65.37
Nonvested Balance at December 31, 2019 (in dollars per share) | $ / shares	$ 72.30
Performance Based Restricted Stock Units
Number of Stock Units
Nonvested Balance at Beginning of Year (in shares) | shares	360,820
Grants in Period (in shares) | shares	340,579
Vested in Period (in shares) | shares	(165,672)
Forfeited in Period (in shares) | shares	(32,870)
Nonvested Balance at December 31, 2019 (in shares) | shares	502,857
Weighted- average Grant-date Fair Value Per Unit
Nonvested Balance at Beginning of Year (in dollars per share) | $ / shares	$ 66.42
Granted (in dollars per share) | $ / shares	74.99
Vested (in dollars per share) | $ / shares	45.90
Forfeited (in dollars per share) | $ / shares	79.69
Nonvested Balance at December 31, 2019 (in dollars per share) | $ / shares	$ 78.12