Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Schedule Of Future Minimum Lease Payments For Operating And Capital Leases [Table Text Block]

In thousands	Operating leases		Capital leases		Minimum lease payments
2017	$	5,476	$	156	$	5,632
2018	5,385		3		5,388
2019	5,340		—		5,340
2020	2,835		—		2,835
2021	930		—		930
Thereafter	28,895		—		28,895
Total	$	48,861	$	159	$	49,020

Long-term Purchase Commitment [Table Text Block]

In thousands	Gas Purchase Agreements		Pipeline Capacity Purchase Agreements		Pipeline Capacity Release Agreements
2017	$	78,587	$	81,206	$	4,487
2018	—		79,741		3,739
2019	—		77,125		—
2020	—		72,021		—
2021	—		45,971		—
Thereafter	—		296,592		—
Total	78,587		652,656		8,226
Less: Amount representing interest	220		101,576		94
Total at present value	$	78,367	$	551,080	$	8,132