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Derivatives and Hedging - Outstanding Derivatives Contracts (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 USD ($) | Dec. 31, 2020 USD ($) outstanding_contract loan | Dec. 31, 2019 USD ($) outstanding_contract | Dec. 31, 2018 USD ($) | Jun. 22, 2020 USD ($)
Derivatives, Fair Value [Line Items] |  |  |  |  |
Number of Contracts | outstanding_contract |  | 167 | 180 |  |
Notional Amounts |  | $ 1,830,063,000 | $ 2,004,858,000 |  |
Fair Value Asset (Liability), Net |  | (110,689,000) | (64,772,000) |  |
Unrealized Loss Recorded in AOCI/L |  | (78,104,000) | (47,164,000) |  |
Repayments of long-term debt |  | 2,058,469,000 | $ 102,579,000 | $ 570,972,000 |
Variable rate debt |  | 200,000,000.0 |  |  |
Senior Notes Due 2028 | Senior Notes |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Aggregate principal amount |  | $ 800,000,000.0 |  |  | $ 800,000,000
Secured Debt | 2016 Credit Facility Agreement | Term Loan A |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Repayments of long-term debt | $ 787,900,000 |  |  |  |
Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Number of Contracts | loan |  | 4 |  |  |
Notional Amounts |  | $ 1,400,000,000 |  |  |
Other liabilities | Interest rate swaps | Designated as hedging instrument |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Number of Contracts | outstanding_contract |  | 4 | 4 |  |
Notional Amounts |  | $ 1,400,000,000 | $ 1,400,000,000 |  |
Fair Value Asset (Liability), Net |  | (74,289,000) | (64,831,000) |  |
Unrealized Loss Recorded in AOCI/L |  | (78,104,000) | $ (47,164,000) |  |
Accrued liabilities | Interest rate swaps | Designated as hedging instrument |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Fair Value Asset (Liability), Net |  | $ (34,886,000) |  |  |
Accrued liabilities | Foreign currency forward contracts | Not Designated as Hedging Instrument |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Number of Contracts | outstanding_contract |  | 163 |  |  |
Notional Amounts |  | $ 430,063,000 |  |  |
Fair Value Asset (Liability), Net |  | (1,514,000) |  |  |
Unrealized Loss Recorded in AOCI/L |  | $ 0 |  |  |
Other current assets | Foreign currency forward contracts | Not Designated as Hedging Instrument |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Number of Contracts | outstanding_contract |  |  | 176 |  |
Notional Amounts |  |  | $ 604,858,000 |  |
Fair Value Asset (Liability), Net |  |  | 59,000 |  |
Unrealized Loss Recorded in AOCI/L |  |  | $ 0 |  |

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