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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Long-Term Debt (Details) - USD ($) $ in Thousands			1 Months Ended
Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 15, 2021	Jun. 30, 2016	Jun. 30, 2016	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Unamortized discounts and issuance costs of unsecured notes				$ 3,368	$ 4,316
Long-term debt				421,632	420,684
Senior unsecured notes, maturity date	Jun. 15, 2021
Unsecured notes
Debt Instrument [Line Items]
Long-term Debt, Gross				$ 425,000	$ 425,000
Three Point One Two Five Percent Senior Unsecured Notes Due June Fifteenth Twenty Twenty Five [Domain]
Debt Instrument [Line Items]
Senior unsecured notes, issued amount		$ 425,000	$ 425,000
Senior unsecured notes, interest rate		3.125%	3.125%
Senior unsecured notes, proceeds		$ 421,000
Term of agreement			5 years