Related Party Transactions (Tables)

6 Months Ended

Jun. 30, 2016

Related Party Transactions [Abstract]

Schedule of Related Party Transactions [Table Text Block]

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2016		2015		2016		2015
	(In thousands)
Indirect charges:
Operating and maintenance expenses	$	10,250	$	8,680	$	20,459	$	17,687
Selling, general and administrative expenses	2,097		2,287		3,913		4,270
Total indirect charges	$	12,347	$	10,967	$	24,372	$	21,957