Debt (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule of Maturities of Long-term Debt [Table Text Block]

The following table summarizes the maturities of the Company’s indebtedness as of December 31, 2017:

	Sr. Unsecured Revolving Credit Facility Maturing 2021			Sr. Unsecured Term Loan Credit Facility		5.0% Sr. Notes Maturing  2021			1.875% Sr. Notes Maturing  2026			Other Debt Facilities		Financing Lease Obligations		Total
	(In thousands)
2018	$	—		$	200,000	$	—		$	—		$	16,015	$	1,370	$	217,385
2019	—			—		—			—			12,974		1,532		14,506
2020	—			—		—			—			7,752		1,597		9,349
2021	625,000			—		500,000			—			9,248		1,664		1,135,912
2022	—			—		—			—			4,664		1,639		6,303
2023 and thereafter	—			—		—			600,700			9,562		28,109		638,371
Total before unamortized discount and debt issuance costs	625,000			200,000		500,000			600,700			60,215		35,911		2,021,826
Unamortized discount and debt issuance costs	(3,339		)	—		(3,417		)	(8,961		)	—		—		(15,717		)
Total	$	621,661		$	200,000	$	496,583		$	591,739		$	60,215	$	35,911	$	2,006,109