Long-Term Debt - Maturity Schedule (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Maturities
2019 (three months)	$ 161
2020	340,534
2021	4,683
2022	889,000
2023	0
Thereafter	996,458
Total	2,230,836
Revolving Credit Facility
Maturities
2022	889,000
Total	889,000
Senior unsecured notes
Maturities
2019 (three months)	0
2020	339,886
Thereafter	996,458
Total	1,336,344
Other long-term debt
Maturities
2019 (three months)	161
2020	648
2021	4,683
Total	$ 5,492

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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