Debt Obligations (Tables)

12 Months Ended

Dec. 31, 2016

Debt Instrument [Line Items]

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

Debt obligations consist of the following as of December 31, 2016 and 2015:

	As of December 31,
(in thousands)	2016			2015
Credit Facility:
Term loan, due 2019	$	60,000		$	67,031
Revolving credit agreements, due 2019	159,963			7,701
	219,963			74,732
Convertible Debt:
1.50% convertible notes, unsecured, due 2044	358,293			347,878
Other obligations	23,892			5,731
Total debt obligations	$	602,148		$	428,341
Unamortized debt issuance costs	(8,324		)	(10,809		)
Carrying value of debt	$	593,824		$	417,532
Short-term debt obligations and current maturities of long-term debt obligations	(32,161		)	(12,060		)
Long-term debt obligations	$	561,663		$	405,472