Long-Term Debt (Tables)

9 Months Ended

Sep. 30, 2017

Debt Disclosure [Abstract]

Schedule of Debt

(In thousands)	September 30, 2017		December 31, 2016
2006 Senior Notes payable through 2021, 5.41%, net of debt issuance costs	$	33,333	$	33,333
2010 Senior Notes payable through 2021, 4.00%, net of debt issuance costs	100,000		100,000
2016 Senior Notes payable through 2031, 3.40%, net of debt issuance costs	73,511		67,713
Senior revolving credit facility maturing in 2020, net of debt issuance costs	265,540		189,456
Total	472,384		390,502
Amounts due within one year, net of debt issuance costs	26,667		26,666
Long-term debt, net of debt issuance costs	$	445,717	$	363,836