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.

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Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Credit Facilities - Outstanding Balance Under Credit Agreement (Details) € in Thousands, £ in Thousands, $ in Thousands	Sep. 30, 2020 USD ($)	Sep. 30, 2020 $ / £	Sep. 30, 2020 $ / €	Sep. 30, 2020 GBP (£)	Sep. 30, 2020 EUR (€)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 $ / £	Dec. 31, 2019 $ / €	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 EUR (€)
Line of Credit Facility [Line Items]
Revolving credit facility (Note 5)	$ 264,009					$ 199,071
Term Loan, Net	417,072					397,893
Foreign currency exchange rate (GBP, EUR, CAD per USD)		1.29	1.17				1.32	1.12
KeyBank National Association \| Credit Facility \| Unsecured debt
Line of Credit Facility [Line Items]
Total Credit Facility	681,081					596,964
KeyBank National Association \| Credit Facility \| Unsecured debt \| USD
Line of Credit Facility [Line Items]
Total Credit Facility	183,211					62,211
KeyBank National Association \| Credit Facility \| Unsecured debt \| GBP
Line of Credit Facility [Line Items]
Total Credit Facility \| £				£ 40,000					£ 40,000
KeyBank National Association \| Credit Facility \| Unsecured debt \| EUR
Line of Credit Facility [Line Items]
Total Credit Facility \| €					€ 384,551					€ 434,551
KeyBank National Association \| Credit Facility \| Unsecured debt \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Revolving credit facility (Note 5)	264,009					199,071
KeyBank National Association \| Credit Facility \| Unsecured debt \| Revolving Credit Facility \| USD
Line of Credit Facility [Line Items]
Revolving credit facility (Note 5)	183,211					62,211
KeyBank National Association \| Credit Facility \| Unsecured debt \| Revolving Credit Facility \| GBP
Line of Credit Facility [Line Items]
Revolving credit facility (Note 5) \| £				40,000					40,000
KeyBank National Association \| Credit Facility \| Unsecured debt \| Revolving Credit Facility \| EUR
Line of Credit Facility [Line Items]
Revolving credit facility (Note 5) \| €					25,000					75,000
KeyBank National Association \| Credit Facility \| Unsecured debt \| Term Facility
Line of Credit Facility [Line Items]
Term Loan	421,560					403,258
Deferred financing costs	(4,488)					(5,365)
Term Loan, Net	417,072					397,893
KeyBank National Association \| Credit Facility \| Unsecured debt \| Term Facility \| USD
Line of Credit Facility [Line Items]
Term Loan	0					0
Deferred financing costs	0					0
Term Loan, Net	$ 0					$ 0
KeyBank National Association \| Credit Facility \| Unsecured debt \| Term Facility \| GBP
Line of Credit Facility [Line Items]
Term Loan \| £				0					0
Deferred financing costs \| £				0					0
Term Loan, Net \| £				£ 0					£ 0
KeyBank National Association \| Credit Facility \| Unsecured debt \| Term Facility \| EUR
Line of Credit Facility [Line Items]
Term Loan \| €					359,551					359,551
Deferred financing costs \| €					0					0
Term Loan, Net \| €					€ 359,551					€ 359,551