Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2018

Long-term Debt and Capital Lease Obligations [Abstract]

Schedule of Long-Term Debt

Long-term debt, principally to banks and bondholders, consists of:

(in thousands, except interest rates)	June 30, 2018	December 31, 2017
Revolving credit agreement with borrowings outstanding at an end of period interest rate of 3.58% in 2018 and 3.40% in 2017 (including the effect of interest rate hedging transactions, as described below), due in 2022	$511,000	$501,000
Obligation under capital lease, matures 2022	14,030	14,919
Long-term debt	525,030	515,919
Less: current portion	(1,844)	(1,799)
Long-term debt, net of current portion	$523,186	$514,120

Schedule of Future Minimum Annual Capital Lease Obilgations

The following schedule presents future minimum annual lease payments under the capital lease obligation and the present value of the minimum lease payments, as of June 30, 2018.

Years ending December 31,	(in thousands)
2018	$1,236
2019	2,473
2020	2,520
2021	2,520
2022	7,373
Total minimum lease payments	16,122
Less:  Amount representing interest	(2,092)
Present value of minimum lease payments	$14,030