Segment Reporting - Summary of Financial Information for Reportable Segments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) reportable_segment	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | reportable_segment			2
Operating revenues, net	$ 56,430	$ 25,681	$ 104,116	$ 43,487
Depreciation, accretion and amortization	13,025	3,336	27,597	6,071
Other operating costs and expenses	26,105	24,586	56,526	33,361
Interest expense, net	28,975	28,186	62,638	45,007
Other non-operating (income) expenses	(19,417)	(7,080)	(44,997)	(7,498)
Income tax expense (benefit)	2,061	(668)	2,919	450
Net income (loss)	5,681	(22,679)	(567)	(33,904)
Total assets	2,655,785		2,655,785		$ 2,687,166
Operating segments | Solar
Segment Reporting Information [Line Items]
Operating revenues, net	28,878	22,017	57,617	39,823
Depreciation, accretion and amortization	6,509	3,738	12,381	6,473
Other operating costs and expenses	4,703	7,990	11,273	9,312
Interest expense, net	10,372	12,863	22,634	23,247
Other non-operating (income) expenses	14,304	(6,640)	18,549	(7,058)
Income tax expense (benefit)	0	0	0	0
Net income (loss)	(7,010)	4,066	(7,220)	7,849
Total assets	671,131		671,131		764,475
Operating segments | Wind
Segment Reporting Information [Line Items]
Operating revenues, net	27,552	3,664	46,499	3,664
Depreciation, accretion and amortization	6,516	(402)	15,216	(402)
Other operating costs and expenses	5,899	4,085	13,328	4,085
Interest expense, net	(281)	725	(2,049)	725
Other non-operating (income) expenses	1,053	(440)	3,042	(440)
Income tax expense (benefit)	0	0	0	0
Net income (loss)	14,365	(304)	16,962	(304)
Total assets	431,578		431,578		375,683
Corporate
Segment Reporting Information [Line Items]
Operating revenues, net	0	0	0	0
Depreciation, accretion and amortization	0	0	0	0
Other operating costs and expenses	15,503	12,510	31,925	19,963
Interest expense, net	18,884	14,598	42,053	21,036
Other non-operating (income) expenses	(34,774)	0	(66,588)	0
Income tax expense (benefit)	2,061	(668)	2,919	450
Net income (loss)	(1,674)	$ (26,440)	(10,309)	$ (41,449)
Total assets	$ 1,553,076		$ 1,553,076		$ 1,547,008