Short and Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule Of Outstanding Debt

	December 31,
(In thousands)	2017		2016
2006 Senior Notes payable through 2021, 5.41%, net of debt issuance costs	$	26,667	$	33,333
2010 Senior Notes payable through 2021, 4.00%, net of debt issuance costs	80,000		100,000
2016 Senior Notes payable through 2031, 3.40%, net of debt issuance costs	74,139		67,713
Senior revolving credit facility maturing in 2020, net of debt issuance costs	293,693		189,456
Total	474,499		390,502
Amounts due within one year	26,667		26,666
Long-term debt	$	447,832	$	363,836