Fair Value Measurements - Schedule of Estimated Fair Values and Carrying Amounts of Financial Instruments Not Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Nonrecurring - USD ($) $ in Thousands		Sep. 30, 2020	Dec. 31, 2019
Notes Payable to Banks [Member] | Term Loans [Member] | Carrying Amount [Member] | Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[1]	$ 4,875,671	$ 5,810,422
Notes Payable to Banks [Member] | Term Loans [Member] | Fair Value [Member] | Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[1]	4,834,838	5,915,451
Revolving loans [Member] | Carrying Amount [Member] | Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[1]	225,000
Revolving loans [Member] | Fair Value [Member] | Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[1]	225,892
Senior Subordinated Notes [Member] | 5.625 % Due 2024 [Member] | Carrying Amount [Member] | Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[2]		890,045
Senior Subordinated Notes [Member] | 5.625 % Due 2024 [Member] | Fair Value [Member] | Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[2]		938,250
Senior Subordinated Notes [Member] | 5.625 % Due 2027 [Member] | Carrying Amount [Member] | Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[2]	1,791,185	1,792,121
Senior Subordinated Notes [Member] | 5.625 % Due 2027 [Member] | Fair Value [Member] | Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[2]	1,865,325	$ 1,883,175
Senior Subordinated Notes [Member] | 4.75% Due 2028 [Member] | Carrying Amount [Member] | Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[2]	990,684
Senior Subordinated Notes [Member] | 4.75% Due 2028 [Member] | Fair Value [Member] | Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying Amount and Fair Value of Financial Instrument	[2]	$ 1,017,500

[1] The fair value of senior secured credit facilities is computed based on borrowing rates currently available to the Company for bank loans with similar terms and average maturities. These fair value measurements are considered Level 3, as significant inputs to the fair value calculation are unobservable in the market.

[2] The fair value of the Company’s fixed rate debt is estimated based on bid prices obtained from an investment banking firm that regularly makes a market for these financial instruments. These fair value measurements are considered Level 2, as quoted market prices are available for low volume trading of these securities.