Debt (Tables)

3 Months Ended

Mar. 31, 2017

Debt Instrument [Line Items]

Schedule of Debt [Table Text Block]

Long-term Debt consisted of the following: 

	(in thousands)	Mar 31, 2017			Dec 31, 2016
4.650% Senior Notes due 2024:
	Principal amount of the notes	$	500,000		$	500,000
	Issuance costs, net of amortization	(5,214		)	(5,385		)
	Fair value of interest rate swaps on $200 million of principal	(878		)	(1,557		)
Term Loan Facility		300,000			300,000
Revolving Credit Facility		—			—
Long-term Debt		$	793,908		$	793,058