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

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Weighted average interest rate of debt outstanding.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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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.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Debt - Debt Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	May 20, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance lease obligations	$ 33,077
Total debt	1,681,369		$ 1,385,162
Less current portion and short-term notes	488,234		195,445
Long-term Debt	$ 1,193,135		1,189,717
5.75% debentures due November 2040
Debt Instrument [Line Items]
Stated interest rate (percent)	5.75%
Long-term debt	$ 599,244		599,208
4.375% debentures due November 2021
Debt Instrument [Line Items]
Stated interest rate (percent)	4.375%
Long-term debt	$ 249,428		249,116
9.2% debentures due August 2021
Debt Instrument [Line Items]
Stated interest rate (percent)	9.20%
Long-term debt	$ 4,318		4,315
1.00% Euro loan due May 2021
Debt Instrument [Line Items]
Stated interest rate (percent)	1.00%
Long-term debt	$ 167,272		169,976
Term loan, due May 2020 \| Term Loan Facility
Debt Instrument [Line Items]
Long-term debt	200,000	$ 200,000	0
Term loan, due July 2022
Debt Instrument [Line Items]
Long-term debt	$ 146,569		$ 158,949
Commercial paper, average rate of 2.40% in 2019 and 2.15% in 2018
Debt Instrument [Line Items]
Weighted average interest rate (percent)	2.40%		2.15%
Long-term debt	$ 250,000		$ 120,000
Other foreign denominated debt, average rate of 5.3% in 2019 and 3.7% in 2018
Debt Instrument [Line Items]
Weighted average interest rate (percent)	5.30%		3.70%
Long-term debt	$ 16,734		$ 57,867
Other notes
Debt Instrument [Line Items]
Long-term debt	$ 14,727		$ 25,731