Revenue Recognition (Tables)

6 Months Ended

Jun. 30, 2018

Revenue Recognition

Schedule of sales to members

	Three Months Ended June 30,				Six Months Ended June 30,
		(dollars in thousands)				(dollars in thousands)
		2018		2017		2018		2017
Capacity revenues	$	231,571	$	229,946	$	472,052	$	467,377
Energy revenues		134,240		131,377		267,160		248,090
Total	$	365,811	$	361,323	$	739,212	$	715,467

Schedule of opening and closing balances of receivables from contracts with customers

		(dollars in thousands)
		June 30, 2018		June 30, 2017		December 31, 2017		December 31, 2016
Receivables from members	$	144,865	$	132,703	$	126,211	$	136,552