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Long-term Debt Long-term Debt - Narrative (Details) |  |  | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 12, 2020 USD ($) | Mar. 24, 2020 USD ($) | Sep. 30, 2020 USD ($) | May 24, 2018 USD ($)
Line of Credit Facility [Line Items] |  |  |  |
Maturities of long-term debt, 2020 |  |  | $ 0.0 |
Maturities of long-term debt, 2021 |  |  | 0.0 |
Maturities of long-term debt, 2022 |  |  | 0.0 |
Maturities of long-term debt, 2023 |  |  | 0.0 |
Maturities of long-term debt, 2024 |  |  | 0.0 |
Maturities of long-term debt, 2025 |  |  | 115,000,000.0 |
Maturities of long-term debt, thereafter |  |  | $ 800,000,000.0 |
Senior Notes |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Stated interest rate |  |  | 5.375% |
New Credit Facility | Secured Debt | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Credit agreement, maximum borrowing capacity |  |  |  | $ 500,000,000
New Credit Facility | Secured Debt | Term Loan Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Credit agreement, maximum borrowing capacity |  |  |  | 50,000,000
New Credit Facility | Secured Debt | Canadian Dollar Term Loan Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Credit agreement, maximum borrowing capacity |  |  |  | $ 250,000,000
Amendment No. 1 to Credit Agreement |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Amount available under revolving credit facility |  |  | $ 568,900,000 |
Weighted average interest rate on borrowings |  |  | 1.40% |
Amendment No. 1 to Credit Agreement | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Unused capacity commitment fee percentage |  |  | 0.175% |
Long-term debt |  |  | $ 115,000,000.0 |
Amendment No. 1 to Credit Agreement | Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Long-term debt |  |  | $ 66,100,000 |
Amendment No. 1 to Credit Agreement | Secured Debt |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Increase in maximum borrowing capacity under certain conditions |  | $ 250,000,000 |  |
Line of credit facility covenant, percentage of EBITDA |  | 65.00% |  |
Maximum leverage ratio required for future credit increase |  | 2.50 |  |
Maximum leverage ratio |  | 4.00 |  |
Maximum leverage ratio after material acquisition |  | 4.50 |  |
Minimum interest coverage ratio amount |  | 3.00 |  |
Amendment No. 1 to Credit Agreement | Secured Debt | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Credit agreement, maximum borrowing capacity |  | $ 750,000,000 |  |
Senior Notes Due 2028 | Senior Notes |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Aggregate principal amount of debt issued | $ 400,000,000 |  |  |
Stated interest rate | 4.125% |  |  |
Redemption price as a percentage | 100.00% |  |  |
Senior Notes Due 2028 | Senior Notes | Prior to June 23, 2023 |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Redemption price as a percentage | 104.125% |  |  |
Redeemable percentage of Senior Notes due 2028 prior to June 30, 2023 | 40.00% |  |  |
Senior Notes Due 2028 | Senior Notes | Twelve months beginning June 30, 2023 |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Redemption price as a percentage | 102.063% |  |  |
Senior Notes Due 2028 | Senior Notes | Twelve months beginning on June 30, 2024 |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Redemption price as a percentage | 101.031% |  |  |
Senior Notes Due 2028 | Senior Notes | After June 30, 2025 |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Redemption price as a percentage | 100.00% |  |  |
Eurocurrency Rate | Amendment No. 1 to Credit Agreement | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  |  | 1.25% |
Eurocurrency Rate | Amendment No. 1 to Credit Agreement | Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  |  | 1.25% |
Base Rate | Amendment No. 1 to Credit Agreement | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  |  | 0.25% |
Base Rate | Amendment No. 1 to Credit Agreement | Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  |  | 0.825% |
Minimum | Amendment No. 1 to Credit Agreement | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Unused capacity commitment fee percentage |  | 0.15% |  |
Minimum | Amendment No. 1 to Credit Agreement | Financial Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  | 1.00% |  |
Minimum | Amendment No. 1 to Credit Agreement | Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  | 1.00% |  |
Minimum | Amendment No. 1 to Credit Agreement | Performance Letter Of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  | 0.75% |  |
Minimum | Eurocurrency Rate | Amendment No. 1 to Credit Agreement |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  | 1.00% |  |
Minimum | Eurocurrency Rate | Amendment No. 1 to Credit Agreement | Term Loan Credit Facility | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  | 1.00% |  |
Minimum | Base Rate | Amendment No. 1 to Credit Agreement |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  | 0.00% |  |
Maximum | Amendment No. 1 to Credit Agreement | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Unused capacity commitment fee percentage |  | 0.225% |  |
Maximum | Amendment No. 1 to Credit Agreement | Financial Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  | 1.75% |  |
Maximum | Amendment No. 1 to Credit Agreement | Letter of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  | 1.75% |  |
Maximum | Amendment No. 1 to Credit Agreement | Performance Letter Of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Letter of credit fee |  | 1.05% |  |
Maximum | Eurocurrency Rate | Amendment No. 1 to Credit Agreement |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  | 1.75% |  |
Maximum | Eurocurrency Rate | Amendment No. 1 to Credit Agreement | Term Loan Credit Facility | Revolving Credit Facility |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  | 1.75% |  |
Maximum | Base Rate | Amendment No. 1 to Credit Agreement |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Margin on rate |  | 0.75% |  |

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