Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2019

Summary of Significant Accounting Policies [Abstract]

Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]

	June 30, 2019		December 31, 2018
	(In thousands)
Cash and cash equivalents	$	243,684	$	198,850
Restricted cash(1):
Included in Other current assets	5,716		7,007
Included in Deferred charges and other assets	1,745		1,727
Total restricted cash	7,461		8,734
Total cash, cash equivalents, and restricted cash	$	251,145	$	207,584