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Debt - Borrowings (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Instrument [Line Items] |  |
Principal amount outstanding | $ 1,995,919 | $ 2,006,046
Less: deferred financing fees | (26,322) | (27,245)
Net balance sheet carrying amount | 1,969,597 | 1,978,801
Term Loan Facility | 2020 Credit Agreement |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 390,000 | 395,000
Line of Credit | Revolving credit facility | 2020 Credit Agreement |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 0 | 5,000
Senior Notes | Senior Notes Due 2028 |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 800,000 | 800,000
Senior Notes | Senior Notes Due 2030 |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | 800,000 | 800,000
Other |  |
Debt Instrument [Line Items] |  |
Principal amount outstanding | $ 5,919 | $ 6,046

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- Definition Amount, after accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section S45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336 + Details
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