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Debt - Debt Outstanding Footnotes (Details) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 28, 2020 USD ($) | Dec. 31, 2020 USD ($) loan | Jun. 22, 2020 USD ($) | Dec. 31, 2019 USD ($)
Debt Instrument [Line Items] |  |  |  |
Principal amount outstanding |  | $ 2,006,046,000 |  | $ 2,207,514,000
Weighted average annual effective rate |  | 4.75% |  |
Connecticut Economic Development Program |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Number of loans | loan |  | 2 |  |
2020 Credit Agreement | Term Loan Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Contractual annualized interest rate |  | 1.56% |  |
Floating eurodollar base rate |  | 0.1875% |  |
Additional interest above base rate |  | 1.375% |  |
Aggregate principal amount | $ 400,000,000 |  |  |
Debt instrument term | 5 years |  |  |
Principal amount outstanding |  | $ 395,000,000 |  | 0
2020 Credit Agreement | Revolving Credit Facility | Line of Credit |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Remaining borrowing capacity |  | 1,000,000,000.0 |  |
Debt instrument term | 5 years |  |  |
Principal amount outstanding |  | 5,000,000 |  | 0
Senior Notes Due 2028 | Senior notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Aggregate principal amount |  | 800,000,000.0 | $ 800,000,000 |
Debt instrument, fixed interest rate |  |  | 4.50% |
Principal amount outstanding |  | 800,000,000 |  | 0
Senior Notes Due 2030 | Senior notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Aggregate principal amount | $ 800,000,000 | $ 800,000,000.0 |  |
Debt instrument, fixed interest rate | 3.75% | 3.75% |  |
Principal amount outstanding |  | $ 800,000,000 |  | $ 0
Economic Development Loan 1 | Connecticut Economic Development Program |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, fixed interest rate |  | 3.00% |  |
Debt instrument term |  | 10 years |  |
Principal amount outstanding |  | $ 1,000,000.0 |  |
Economic Development Loan 2 | Connecticut Economic Development Program |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, fixed interest rate |  | 1.75% |  |
Debt instrument term |  | 10 years |  |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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