Pattern Energy 10-K 2 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 26, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	PEGI
Entity Registrant Name	Pattern Energy Group Inc.
Entity Central Index Key	1561660
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		69,062,463
Entity Public Float			$1,308,252,717

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$101,656	$103,569
Restricted cash	7,945
Trade receivables	35,759	20,951
Related party receivable	671	167
Reimbursable interconnection costs	2,532	3,967
Derivative assets, current	18,506	13,937
Current deferred tax assets	318	573
Prepaid expenses and other current assets	27,954	11,415
Deferred financing costs, current, net of accumulated amortization of $22,749 and $16,225 as of December 31, 2014 and 2013, respectively	13,615	5,456
Total current assets	208,956	160,035
Restricted cash	39,745	32,636
Turbine advances	79,637
Construction in progress	26,195
Property, plant and equipment - net of accumulated depreciation	2,350,856	1,476,142
Unconsolidated investments	29,079	107,055
Derivative assets	49,369	82,167
Deferred financing costs	30,053	30,336
Net deferred tax assets	5,474	2,017
Other assets	12,678	13,243
Total assets	2,832,042	1,903,631
Current liabilities:
Accounts payable and other accrued liabilities	24,793	15,550
Accrued construction costs	20,132	3,204
Related party payable	5,757	1,245
Accrued interest	3,634	495
Dividends payable	15,734	11,103
Derivative liabilities, current	16,307	16,171
Revolving credit facility	50,000
Current portion of long-term debt	121,561	48,851
Current net deferred tax liabilities	149
Current portion of contingent liabilities	4,000
Total current liabilities	262,067	96,619
Long-term debt	1,329,052	1,200,367
Derivative liabilities	17,467	7,439
Asset retirement obligations	29,272	20,834
Net deferred tax liabilities	20,418	9,930
Other long-term liabilities	9,032	438
Total liabilities	1,667,308	1,335,627
Equity:
Additional paid-in capital	723,938	489,412
Accumulated loss	-44,626	-13,336
Accumulated other comprehensive loss	-53,913	-17,377
Total equity before noncontrolling interest	634,148	468,210
Noncontrolling interest	530,586	99,794
Total equity	1,164,734	568,004
Total liabilities and equity	2,832,042	1,903,631
Controlling Interest [Member]
Equity:
Accumulated other comprehensive loss	-45,068	-8,353
Total equity	634,148	468,210
Class A Common Stock [Member]
Equity:
Common stock value	621	355
Treasury stock, at cost; 25,465 and 934 shares of Class A common stock as of December 31, 2014 and 2013, respectively	-717	-24
Class A Common Stock [Member] | Controlling Interest [Member]
Equity:
Total equity	621	355
Class B Convertible Common Stock [Member]
Equity:
Common stock value		$156

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Deferred financing costs, current, accumulated amortization	$22,749	$16,225
Property, plant and equipment, accumulated depreciation	$278,291	$179,778
Class A Common Stock [Member]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	62,088,306	35,531,720
Common stock, shares outstanding	62,062,841	35,530,786
Treasury stock, shares	25,465	934
Class B Convertible Common Stock [Member]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	0	15,555,000
Common stock, shares outstanding	0	15,555,000

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue:
Electricity sales	$245,022,000	$173,270,000	$101,835,000
Energy derivative settlements	13,525,000	16,798,000	19,644,000
Unrealized loss on energy derivative	-3,878,000	-11,272,000	-6,951,000
Related party revenue	3,317,000	911,000
Other revenue	7,507,000	21,866,000
Total revenue	265,493,000	201,573,000	114,528,000
Cost of revenue:
Project expense	77,775,000	57,677,000	34,843,000
Depreciation and accretion	104,417,000	83,180,000	49,027,000
Total cost of revenue	182,192,000	140,857,000	83,870,000
Gross profit	83,301,000	60,716,000	30,658,000
Operating expenses:
Development expense			174,000
General and administrative	22,533,000	4,819,000	858,000
Related party general and administrative	5,787,000	8,169,000	10,604,000
Total operating expenses	28,320,000	12,988,000	11,636,000
Operating income (loss)	54,981,000	47,728,000	19,022,000
Other income (expense):
Interest expense	-67,694,000	-63,614,000	-36,502,000
Interest rate derivative settlements	-4,075,000	-2,099,000
Unrealized (loss) gain on derivatives	-11,668,000	15,601,000	-4,953,000
Equity in (losses) earnings in unconsolidated investments	-25,295,000	7,846,000	-40,000
Related party income	2,612,000	665,000
Net gain on transactions	13,843,000	5,995,000	4,173,000
Other income, net	433,000	2,496,000	1,320,000
Other (expense) income	-91,844,000	-33,110,000	-36,002,000
Net (loss) income before income tax	-36,863,000	14,618,000	-16,980,000
Tax provision (benefit)	3,136,000	4,546,000	-3,604,000
Net (loss) income	-39,999,000	10,072,000	-13,376,000
Net loss attributable to noncontrolling interest	-8,709,000	-6,887,000	-7,089,000
Net (loss) income attributable to controlling interest	-31,290,000	16,959,000	-6,287,000
Earnings per share information:
Less: Net income attributable to controlling interest prior to the IPO on October 2, 2013		-30,295,000
Net loss attributable to controlling interest subsequent to the IPO		-13,336,000
Deemed dividends on Class B common shares	21,901,000
Net loss attributable to common stockholders	-110,167,000	-24,439,000
Pro Forma [Member]
Other income (expense):
Net (loss) income before income tax			-16,980,000
Tax provision (benefit)			818,000
Net (loss) income			-17,798,000
Class A Common Stock [Member]
Earnings per share information:
Cash dividends declared on Class A common shares	-56,976,000	-11,103,000
Weighted average number of shares:
Basic and diluted common stock	42,361,959	35,448,056
Earnings (loss) per share
Basic and diluted loss per share	($0.56)	($0.17)
Cash dividends declared per Class A common share	$1.30	$0.31
Class B Common Stock [Member]
Earnings per share information:
Deemed dividends on Class B common shares	($21,901,000)
Weighted average number of shares:
Basic and diluted common stock	15,555,000	15,555,000
Earnings (loss) per share
Basic and diluted loss per share	($0.49)	($0.48)
Deemed dividends per Class B common share	$1.41

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive (Loss) Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net (loss) income	($39,999)	$10,072	($13,376)
Other comprehensive (loss) income:
Foreign currency translation, net of tax impact of $0, $0, and $0, respectively	-10,875	-8,309	2,749
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit of $734, $0 and $0, respectively	-5,896	48,818	-5,469
Reclassifications to net loss, net of tax impact of $404, $0 and $0, respectively	-13,774	-11,943	-5,701
Total change in effective portion of change in fair market value of derivatives	-19,670	36,875	-11,170
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax benefit (provision) of $1,855, ($615) and $302, respectively	-5,991	2,473	-1,475
Total other comprehensive (loss) income, net of tax	-36,536	31,039	-9,896
Comprehensive (loss) income	-76,535	41,111	-23,272
Less comprehensive (loss) income attributable to noncontrolling interest:
Net loss attributable to noncontrolling interest	-8,709	-6,887	-7,089
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit of $220, $0 and $0, respectively	-5,896	48,818	-5,469
Comprehensive loss attributable to noncontrolling interest	-8,530	-1,799	-7,873
Comprehensive (loss) income	-68,005	42,910	-15,399
Noncontrolling Interest [Member]
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit of $734, $0 and $0, respectively	3,780	6,992	1,116
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit of $220, $0 and $0, respectively	3,780	6,992	1,116
Reclassifications to net loss, net of tax impact of $121, $0 and $0, respectively	-3,601	-1,904	-1,900
Total change in effective portion of change in fair market value of derivatives	$179	$5,088	($784)

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive (Loss) Income (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Foreign currency translation tax impact	$0	$0	$0
Effective portion of change in fair market value of derivatives tax benefit	734	0	0
Reclassifications to net loss tax impact	404	0	0
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax benefit (provision)	1,855	-615	302
Noncontrolling Interest [Member]
Effective portion of change in fair market value of derivatives tax benefit	220	0	0
Reclassifications to net loss tax impact	$121	$0	$0

Consolidated_Statement_of_Stoc

Consolidated Statement of Stockholders' Equity (USD $)	Total	Class A Common Stock [Member]	IPO [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Controlling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member]	Stockholders' Equity, Total [Member]	Stockholders' Equity, Total [Member]	Stockholders' Equity, Total [Member]	Stockholders' Equity, Total [Member]
In Thousands, except Share data	USD ($)	USD ($)	Class A Common Stock [Member]	USD ($)	Class A Common Stock [Member]	Class B Common Stock [Member]	Additional Paid-in Capital [Member]	Capital [Member]	Accumulated Income (Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Contribution Transactions [Member]	Contribution Transactions [Member]	Contribution Transactions [Member]	Contribution Transactions [Member]	Contribution Transactions [Member]	IPO [Member]	IPO [Member]	IPO [Member]	USD ($)	Capital [Member]	Accumulated Income (Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Panhandle 1 [Member]	Panhandle 1 [Member]	Panhandle 2 [Member]	Panhandle 2 [Member]	USD ($)	IPO [Member]	Panhandle 1 [Member]	Panhandle 2 [Member]
					USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	Class A Common Stock [Member]	Class B Common Stock [Member]	Additional Paid-in Capital [Member]	Capital [Member]	Accumulated Income (Deficit) [Member]	USD ($)	Class A Common Stock [Member]	Additional Paid-in Capital [Member]		USD ($)	USD ($)	USD ($)	USD ($)	Capital [Member]	USD ($)	Capital [Member]		USD ($)	USD ($)	USD ($)
												USD ($)	USD ($)	USD ($)	USD ($)	USD ($)		USD ($)	USD ($)						USD ($)		USD ($)
Balance at Dec. 31, 2011				$362,226				$378,188	$9,190	($25,152)										$84,472	$75,475	$19,455	($10,458)					$446,698
Balance, shares at Dec. 31, 2011
Contribution				281,519				281,519																				281,519
Distribution				-114,236				-114,236												-1,298	-1,298							-115,534
Issuance of common stock				1			1																					1
Issuance of common stock, shares					100
Net income (loss)	-13,376			-6,287					-6,287											-7,089		-7,089						-13,376
Other comprehensive (loss) income, net of tax	-9,896			-9,112						-9,112										-784			-784					-9,896
Balance at Dec. 31, 2012				514,111			1	545,471	2,903	-34,264										75,301	74,177	12,366	-11,242					589,412
Balance, shares at Dec. 31, 2012					100
Contribution				32,677				32,677																				32,677
Distribution				-104,634				-104,634												-1,426	-1,426							-106,060
Additional paid-in capital				2			2																					2
Net income (loss)				30,295					30,295											-690		-690						29,605
Other comprehensive (loss) income, net of tax				20,633						20,633										3,559			3,559					24,192
Balance at Sep. 30, 2013				493,084			3	473,514	33,198	-13,631										76,744	72,751	11,676	-7,683					569,828
Balance, shares at Sep. 30, 2013					100
Interest in Gulf Wind retained by Pattern Development				-28,584				-18,332	-13,122	2,870										28,584	18,332	13,122	-2,870
Assumption of liabilities related to Contribution Transactions				-4,207				-4,207																				-4,207
Distribution				-232,640			-232,640																					-232,640
Issuance of Class A restricted common stock				156	1		155																					156
Issuance of Class A restricted common stock, shares					83,183
Issuance of common stock				93			93					194	156	470,701	-450,975	-20,076	317,042	160	316,882									93	317,042
Issuance of common stock, shares					3,437							19,445,000	15,555,000					16,000,000
Repurchase of shares for employee tax withholding				-24							-24																	-24
Repurchase of shares for employee tax withholding, shares											-934
Stock-based compensation				263			263																					263
Dividends declared on Class A common stock				-11,103			-11,103																					-11,103
Acquisition from Pattern Development				-57,852			-54,942			-2,910																		-57,852
Distribution to noncontrolling interest																				-866	-866							-866
Net income (loss)	-19,376			-13,336					-13,336											-6,197		-6,197						-19,533
Other comprehensive (loss) income, net of tax				5,318						5,318										1,529			1,529					6,847
Balance at Dec. 31, 2013	568,004			468,210	355		489,412		-13,336	-8,353	-24									99,794	90,217	18,601	-9,024					568,004
Balance, shares at Dec. 31, 2013		35,530,786			35,531,720						-934
Dividends declared on Class A common stock		-11,179
Net income (loss)	-21,899
Balance at Mar. 31, 2014
Balance, shares at Dec. 31, 2013		35,530,786
Dividends declared on Class A common stock		-26,138
Balance at Jun. 30, 2014
Balance, shares at Dec. 31, 2013		35,530,786
Dividends declared on Class A common stock		-41,395
Balance at Sep. 30, 2014
Balance at Dec. 31, 2013	568,004			468,210	355	156	489,412		-13,336	-8,353	-24									99,794	90,217	18,601	-9,024					568,004
Balance, shares at Dec. 31, 2013					35,531,720	15,555,000					-934
Issuance of common stock related to the public offering, net of issuance costs				286,893	108		286,785																					286,893
Issuance of common stock related to the public offering, shares					10,810,810
Issuance of Class A restricted common stock				3,496	2		3,494																					3,496
Issuance of Class A restricted common stock, shares					175,915
Issuance of common stock				327			327																					327
Issuance of common stock, shares																		14,861
Repurchase of shares for employee tax withholding				-693							-693																	-693
Repurchase of shares for employee tax withholding, shares											-24,531
Conversion of Class B common stock to Class A common stock, amount					156	-156
Conversion of Class B common stock to Class A common stock, shares					15,555,000	-15,555,000
Stock-based compensation				610			610																					610
Refund of issuance costs related to the IPO				286			286																					286
Dividends declared on Class A common stock	-56,976			-56,976			-56,976																					-56,976
Recognition of beneficial conversion feature on Class B convertible common stock				-21,901			-21,901																					-21,901
Adjustment to paid-in capital for beneficial conversion feature recognition				21,901			21,901																					21,901
Accretion of the Class B beneficial conversion feature				21,901			21,901																					21,901
Deemed dividends on Class B convertible common stock				-21,901			-21,901																					-21,901
Sale of Class A membership interests																								210,250	210,250	193,363	193,363			210,250	193,363
Fair value of noncontrolling interest in El Arrayan																				35,259	35,259							35,259
Contribution from noncontrolling interest																				2,550	2,550							2,550
Distribution to noncontrolling interest																				-2,100	-2,100							-2,100
Net income (loss)	-39,999			-31,290					-31,290											-8,709		-8,709						-39,999
Other comprehensive (loss) income, net of tax	-36,536			-36,715						-36,715										179			179					-36,536
Balance at Dec. 31, 2014	$1,164,734			$634,148	$621		$723,938		($44,626)	($45,068)	($717)									$530,586	$529,539	$9,892	($8,845)					$1,164,734
Balance, shares at Dec. 31, 2014		62,062,841			62,088,306						-25,465

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities
Net (loss) income	($39,999)	$10,072	($13,376)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and accretion	104,417	83,180	49,027
Amortization of financing costs	6,309	6,816	2,546
Unrealized loss (gain) on derivatives	15,546	-4,329	11,904
Stock-based compensation	4,105	511
Net gain on transactions	-16,526	-5,995	-4,173
Deferred taxes	2,948	4,546	-3,604
Equity in losses (earnings) in unconsolidated investments	25,295	-7,846	40
Changes in operating assets and liabilities:
Trade receivables	-8,255	-8,721	-298
Reimbursable interconnection receivable		-11
Prepaid expenses and other current assets	12,916	-2,698	-5,842
Other assets (non-current)	-649	-566	-428
Accounts payable and other accrued liabilities	3,667	3,036	-379
Related party receivable/payable	-942	190	-100
Accrued interest payable	1,377	-33	-78
Contingent liabilities			-188
Long-term liabilities	239
Net cash provided by operating activities	110,448	78,152	35,051
Investing activities
Receipt of ITC Cash Grant		173,446	79,910
Cash paid for acquisitions, net of cash acquired	-306,584	-30,070
Proceeds from sale of investments		14,254	4,173
Decrease in restricted cash	46,700	66,517	28,431
Increase in restricted cash	-40,790	-80,569	-36,576
Capital expenditures	-119,506	-123,517	-641,422
Deferred development costs		-528	-7,093
Distribution from unconsolidated investments	22,019	10,463
Contribution to unconsolidated investments	-2,651	-9,678	-22,387
Reimbursable interconnection receivable	3,892	49,715	-47,055
Other assets (non-current)	17,540	2,358	3,066
Net cash (used in) provided by investing activities	-379,380	72,391	-638,953
Financing activities
Proceeds from public offering, net of expenses	286,757	317,926
Proceeds from exercise of stock options	327
Repurchase of shares for employee tax withholding	-693	-24
Dividends paid	-52,344
Payment for acquisition from Pattern Development		-49,430
Capital distributions-Contribution Transactions		-232,640
Capital contributions-Pattern Development		32,679	281,519
Capital contributions-noncontrolling interest	200,805
Capital distributions-Pattern Development		-98,886	-114,236
Capital distributions-noncontrolling interest	-2,100	-2,292	-1,298
Decrease in restricted cash	19,627	122,689	26,669
Increase in restricted cash	-17,903	-127,369	-15,850
Deposit for letters of credit	-3,422
Payment for deferred financing costs	-11,856	-294	-19,989
Payment for deferred equity issuance costs	-550
Proceeds from revolving credit facility	50,000	56,000
Repayment of revolving credit facility		-56,000
Repayment of short-term debt	-210,191
Proceeds from short-term debt	59,778
Repayment of long-term debt	-49,246	-50,324	-27,546
Proceeds from long-term debt		138,620	497,226
Repayment of construction and grant loans		-114,056	-53,328
Net cash provided by (used in) financing activities	268,989	-63,401	573,167
Effect of exchange rate changes on cash and cash equivalents	-1,970	-1,147	637
Net change in cash and cash equivalents	-1,913	85,995	-30,098
Cash and cash equivalents at beginning of period	103,569	17,574	47,672
Cash and cash equivalents at end of period	101,656	103,569	17,574
Supplemental disclosure
Cash payments for income taxes	131
Cash payments for interest expense, net of capitalized interest	53,776	53,295	33,215
Schedule of non-cash activities
Change in fair value of designated interest rate swaps	-22,847	36,875	-11,170
Change in fair value of contingent liabilities			-2,015
Amortization of deferred financing costs-included as construction in progress	343	175	3,824
Change in property, plant and equipment	-47,908	-109,281	79,181
Transfer of capitalized assets to South Kent joint venture		49,275
Non-cash distribution to Pattern Development		-5,748
Assumption of contingent liability related to Contribution Transactions		-4,207
Accrued IPO stock issuance costs		-884
Non-cash deemed dividends on Class B convertible common stock	-21,901
Class B Convertible Common Stock [Member]
Schedule of non-cash activities
Non-cash deemed dividends on Class B convertible common stock	21,901
E1 Arrayan, Panhandle 1, Panhandle 2 and Logans Gap [Member]
Supplemental disclosure
Acquired capitalized assets for El ArrayC!n, Panhandle 1, Panhandle 2, and Logan's Gap	1,013,365
Logan's Gap [Member]
Schedule of non-cash activities
Assumption of contingent liability upon acquisition of Logan's Gap	($4,000)

Organization

Organization	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Organization	1	Organization
	Pattern Energy Group Inc. (“Pattern Energy” or the “Company”) was organized in the state of Delaware on October 2, 2012. Pattern Energy issued 100 shares on October 17, 2012 to Pattern Renewables LP, a 100% owned subsidiary of Pattern Energy Group LP (“Pattern Development”). On September 24, 2013, Pattern Energy’s charter was amended, and the number of shares that Pattern Energy is authorized to issue was increased to 620,000,000 total shares; 500,000,000 of which are designated Class A common stock, 20,000,000 of which were designated Class B common stock, and 100,000,000 of which are designated Preferred Stock. On December 31, 2014, the Company’s Class B common stock was converted into Class A common stock on a one-for-one basis.
	Pattern Energy is an independent energy generation company focused on constructing, owning and operating energy projects with long-term energy sales contracts located in the United States, Canada and Chile. The Company consists of the consolidated operations of certain entities and assets contributed by, or purchased principally from, Pattern Development. The Company owns 100% of Hatchet Ridge Wind, LLC (“Hatchet Ridge”), St. Joseph Windfarm Inc. (“St. Joseph”), Spring Valley Wind LLC (“Spring Valley”), Pattern Santa Isabel LLC (“Santa Isabel”), Ocotillo Express LLC (“Ocotillo”) and Logan’s Gap B Member LLC (“Logan’s Gap”). The Company owns a controlling interest in Pattern Gulf Wind Holdings LLC (“Gulf Wind”), Parque Eólico El Arrayán SpA (“El Arrayán”), Panhandle Wind Holdings LLC (“Panhandle 1”) and Panhandle B Member 2 LLC (“Panhandle 2”) and noncontrolling interests in South Kent Wind LP (“South Kent”) and Grand Renewable Wind LP (“Grand”). The principal business objective of the Company is to produce stable and sustainable cash flows through the generation and sale of energy and to selectively grow our project portfolio.
	Pattern Energy was formed by Pattern Development for the purpose of an initial public offering (“IPO”). For periods prior to October 2, 2013, Pattern Energy was a shell company, with expenses of less than $10,000 for 2013 and 2012. In accordance with ASC 805-50-30-6, the historical financial statements of Pattern Energy’s predecessor, which consist of the combined financial statements of a combination of entities and assets contributed by Pattern Development to Pattern Energy, are consolidated with Pattern Energy from the beginning of the earliest period presented.
	Initial Public Offering and Contribution Transactions
	On October 2, 2013, Pattern Energy issued 16,000,000 shares of Class A common stock in an IPO generating net proceeds of approximately $317.0 million. Concurrent with the IPO, Pattern Energy issued 19,445,000 shares of Class A common stock and 15,555,000 shares of Class B common stock to Pattern Development and utilized approximately $232.6 million of the net proceeds of the IPO as additional consideration to Pattern Development for certain entities and assets contributed to Pattern Energy (“Contribution Transactions”) consisting of interests in eight wind power projects, including six projects in operation (Gulf Wind, Hatchet Ridge, St. Joseph, Spring Valley, Santa Isabel and Ocotillo), and two projects that were under construction (El Arrayán and South Kent) at the time of the IPO. In accordance with the Financial Accounting Standard Board’s (“FASB”) Accounting Standards Codification (“ASC”) 805-50-30-5, Transactions between Entities under Common Control, Pattern Energy recognized the assets and liabilities contributed by Pattern Development at their historical carrying amounts at the date of the Contribution Transactions. On October 8, 2013, Pattern Energy’s underwriters exercised in full their overallotment option to purchase 2,400,000 shares of Class A common stock from Pattern Development, the selling stockholder, pursuant to the overallotment option granted by Pattern Development.
	In connection with the Contribution Transactions, Pattern Development retained a 40% interest in Gulf Wind previously held by it such that, at the completion of the IPO, Pattern Energy, Pattern Development and the joint venture partner held interests of approximately 40%, 27% and 33%, respectively, of the distributable cash flow of Gulf Wind, together with certain allocated tax items.
	Effective with Pattern Energy’s IPO, Pattern Development’s project operations and maintenance personnel and certain of its executive officers became Pattern Energy employees and their employment with Pattern Development was terminated. Pattern Development retained those employees whose primary responsibilities relate to project development, legal, financial or other administrative functions. Pattern Energy entered into a bilateral services agreement with Pattern Development, or the “Management Services Agreement”, that provides for Pattern Energy and Pattern Development to benefit, primarily on a cost-reimbursement basis, from the respective management and other professional, technical and administrative personnel of the respective companies, all of whom report to and are managed by Pattern Energy’s executive officers.
	May 2014 Public Offering
	On May 14, 2014, the Company completed an underwritten public offering of its Class A common stock. In total, 21,117,171 shares of its Class A common stock were sold. Of this amount, the Company issued and sold 10,810,810 shares of Class A common stock and Pattern Development, the selling stockholder, sold 10,306,361 shares of Class A common stock, including 2,754,413 shares upon exercise in full of the underwriters’ overallotment option. Net proceeds generated for the Company were approximately $286.8 million after deducting underwriting discounts and commissions and transaction expenses. The Company did not receive any proceeds from the sale of the shares sold by Pattern Development.
	As a result of the sale of the shares held by Pattern Development, its ownership interest in the Company was reduced from approximately 63% to 35%. Consequently, the Company is no longer subject to ASC 805-50-30-5, Transactions between Entities under Common Control. All future transactions with Pattern Development will be recognized at fair value on the measurement date in accordance with ASC 805 – Business Combinations.

Summary_of_Significant_Account

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2014

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2

Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The accompanying consolidated financial statements have been prepared in accordance with the accounting principles generally accepted in the United States (“U.S. GAAP”). They include the results of wholly-owned and partially-owned subsidiaries in which the Company has a controlling interest with all significant intercompany accounts and transactions eliminated.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates, and such differences may be material to the consolidated financial statements.

Reclassification

Certain prior period balances have been reclassified to conform to current period presentation of the Company’s consolidated financial statements and accompanying notes. Such reclassifications have no effect on previously reported balance sheet subtotals, results of operations or retained earnings.

Unaudited Pro Forma Income Tax

In order to present the tax effect of the Contribution Transactions, the Company has presented a 2012 pro forma income tax provision as if the Contribution Transactions occurred effective January 1, 2012 and as if the Company were under control of a Subchapter C-Corporation for U.S. federal income tax purposes.

Variable Interest Entities

ASC 810, Consolidation of Variable Interest Entities, defines the criteria for determining the existence of Variable Interest Entities (“VIEs”) and provides guidance for consolidation. The Company consolidates VIEs where the Company is the primary beneficiary. The primary beneficiary of a VIE is the party that has the power to direct the activities that most significantly impact the performance of the entity and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the entity.

Investments or joint ventures in which the Company does not have a majority ownership interest and are not VIEs for which the Company is considered the primary beneficiary are accounted for using the equity method. These amounts are included in unconsolidated investments in the consolidated balance sheets.

Acquisitions

Business Combinations

When the Company acquires a controlling interest, the purchase is accounted for using the acquisition method, and the fair value of purchase consideration is allocated to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values. The excess, if any, of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. Conversely, the excess, if any, of the net fair values of identifiable assets and liabilities over the fair value of purchase consideration is recorded as gain. Such valuations require management to make significant estimates and assumptions, especially with respect to intangible assets. These estimates and assumptions are inherently uncertain, and as a result, actual results may differ from estimates. Significant estimates include, but are not limited to, future expected cash flows, useful lives and discount rates. During the measurement period, which is one year from the acquisition date, we may record adjustments to the assets acquired and liabilities assumed, with a corresponding offset to either goodwill or gain, depending on whether the fair value of purchase consideration is in excess of or less than net assets acquired. Upon the conclusion of the measurement period, any subsequent adjustments are recorded to earnings.

Equity Method Investments

When the Company acquires a noncontrolling interest the investment is accounted for using the equity method of accounting and is initially recognized at cost.

Noncontrolling Interests

Noncontrolling interests represent the portion of the Company’s net (loss) income, net assets and comprehensive (loss) income that is not allocable to the Company and is calculated based on ownership percentage, for certain projects.

For the noncontrolling interests in the Company’s Gulf Wind, Panhandle 1 and Panhandle 2 projects, the Company has determined that the operating partnership agreements do not allocate economic benefits pro rata to its two classes of investors and the appropriate methodology for calculating the noncontrolling interest balance that reflects the substantive profit sharing arrangement is a balance sheet approach using the hypothetical liquidation at book value (“HLBV”) method.

Under the HLBV method, the amounts reported as noncontrolling interest in the consolidated balance sheets and consolidated statements of operations represent the amounts the third party would hypothetically receive at each balance sheet reporting date under the liquidation provisions of the operating partnership agreement assuming the net assets of Gulf Wind, Panhandle 1 and Panhandle 2 were liquidated at recorded amounts determined in accordance with U.S. GAAP and distributed to the investors. The third-party interest in the results of operations of Gulf Wind, Panhandle 1 and Panhandle 2 and the Company’s net (loss) income and comprehensive (loss) income is determined as the difference in noncontrolling interests in the consolidated balance sheets at the start and end of each reporting period, after taking into account any capital transactions between Gulf Wind, Panhandle 1, Panhandle 2 and the third party. The noncontrolling interest balances in Gulf Wind, Panhandle 1 and Panhandle 2 are reported as a component of equity in the consolidated balance sheets.

Foreign Currency Translation

The assets and liabilities of foreign subsidiaries, where the local currency is the functional currency, are translated from their respective functional currencies into U.S. dollars at the rates in effect at the balance sheet date and revenue and expense amounts are translated at average rates during the period, with resulting foreign currency translation adjustments recorded in other comprehensive (loss) income, net of tax, in the accompanying consolidated statements of stockholders’ equity and comprehensive (loss) income. Where the U.S. dollar is the functional currency, re-measurement adjustments are recorded in other income, net in the accompanying consolidated statements of operations.

Gains and losses realized from transactions, including related party balances not considered permanent investments, that are denominated in currencies other than an entity’s functional currency are included in other income, net in the accompanying consolidated statements of operations.

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, trade receivables and derivative assets. The Company places its cash and cash equivalents with high quality institutions.

The Company sells electricity and environmental attributes, including renewable energy credits, primarily to creditworthy utilities under long-term, fixed-priced power purchase agreements (“PPAs”) and, in some cases, through individual renewable energy credits sale agreements. During the year ended December 31, 2014, Standard & Poor’s Rating Services (“S&P”) and Moody’s Investor Service (“Moody’s”) downgraded the credit rating of the Puerto Rico Electric Power Authority (“PREPA”) from BBB and Baa3 to CCC and Caa3, respectively. On December 31, 2014, the amount of trade receivables due from PREPA was $2.5 million. As of March 2, 2015, PREPA was current with respect to payments due under the PPA and the next payment will be due from PREPA under the PPA on approximately March 19, 2015.

The table below presents significant customers who accounted for the following percentages of total revenues and the related maximum amount of credit loss based on their percentages of total trade receivables as of December 31, 2014:

Year ended December 31,

2014

2013

2012

Revenue

Trade

Revenue

Trade

Revenue

Trade

Receivables

Receivables

Receivables

San Diego Gas & Electric

22.09

%

14.13

%

16.31

%

26.21

%

0.17

%

9.09

%

Manitoba Hydro

14.47

%

9.39

%

16.69

%

17.18

%

30.23

%

14.08

%

Electric Reliability Council of Texas

14.34

%

15.93

%

11.59

%

2.59

%

17.24

%

3.41

%

NV Energy, Inc.

11.07

%

9.98

%

11.57

%

6.54

%

8.82

%

29.16

%

Pacific Gas & Electric

10.93

%

9.54

%

13.77

%

14.47

%

21.79

%

13.81

%

The Company’s interest rate derivative assets are placed with counterparties that are creditworthy institutions. An additional derivative asset was generated from Credit Suisse Energy LLC, the counterparty to a 10-year fixed-for-floating swap related to annual electricity generation at the Company’s Gulf Wind project. The Company’s reimbursements for prepaid interconnection network upgrades are with large creditworthy utility companies.

Fair Value of Financial Instruments

ASC 820, Fair Value Measurements, defines fair value as the price at which an asset could be exchanged or a liability transferred in an orderly transaction between knowledgeable, willing parties in the principal or most advantageous market for the asset or liability. Where available, fair value is based on observable market prices or derived from such prices. Where observable prices or inputs are not available, valuation models are applied.

These valuation techniques involve some level of management estimation and judgment, the degree of which is dependent on the price transparency for the instruments or market and the instruments’ complexity. See Note 12 on Fair Value Measurements.

U.S. Treasury Grants

The Company received U.S. Treasury grants on certain wind power projects as defined under Section 1603 of the American Recovery and Reinvestment Act of 2009, as amended by the Tax Relief Unemployment Insurance Reauthorization and Job Creation Act of December 2010, upon approval by the U.S. Treasury Department. The Company records the U.S. Treasury grant proceeds as a deduction from the carrying amount of the related asset which results in a reduction of depreciation expense over the life of the asset. The Company records a catch-up adjustment in the period in which the grant is approved to recognize the portion of the grant that proportionally matches the depreciation for the period between the date of placement in service of the wind power project and approval by the U.S. Treasury Department. See Note 5 on Property, Plant and Equipment.

Cash and Cash Equivalents

Cash and cash equivalents consist of all cash balances and highly-liquid investments with original maturities of three months or less. The Company maintains cash and cash equivalents, which consist principally of demand deposits with high credit quality financial institutions. The Company has exposure to credit risk to the extent cash and cash equivalent balances, including restricted cash, exceed amounts covered by federal deposit insurance. The Company believes that its credit risk is immaterial.

Restricted Cash

Restricted cash consists of cash balances which are restricted as to withdrawal or usage and includes cash to collateralize bank letters of credit related primarily to interconnection rights, PPAs and for certain reserves required under the Company’s loan agreements.

Trade Receivables

The Company’s trade receivables are generated by selling energy and renewable energy credits in the California, Texas, Nevada, Manitoba (Canada), Puerto Rico and Chilean energy markets. The Company believes that all amounts are collectible and an allowance for doubtful accounts is not required as of December 31, 2014 and 2013.

Reimbursable Interconnection Costs

The Company may, from time to time, pay to construct interconnection network upgrades on behalf of the Company’s utility customers. The interconnection upgrades are owned by each utility customer who will reimburse the Company with interest when the project reaches commercial operations.

Turbine Advances

Turbine advances represent amounts advanced to turbine suppliers for the manufacture of wind turbines in accordance with turbine supply agreements for the Company’s wind power projects and for which the Company has not taken title. Turbine advances are reclassified to construction in progress when the Company takes legal title to the related turbines and are reclassified to property, plant and equipment when the project achieves commercial operation. Depreciation does not commence until projects enter commercial operation and turbine assets are placed in service.

Deferred Development Costs

Deferred development costs represent the accumulated costs of initial permitting, environmental reviews, land rights and obligations and preliminary design and engineering work. The Company expenses all project development costs until a project is determined to be technically feasible and likely to achieve commercial success. Upon commencement of construction, deferred development costs are recorded as a component of construction in progress. Upon achievement of commercial operation, construction in progress, which includes deferred development costs, is reclassified to property, plant and equipment.

Construction in Progress

Construction in progress represents the accumulated costs of projects in construction. Construction costs include turbines for which the Company has taken legal title, civil engineering, electrical and other related costs. Other capitalized costs include reclassified deferred development costs, amortization of intangible assets, amortization of deferred financing costs, capitalized interest and other costs required to place a project into commercial operation. Construction in progress is reclassified to property, plant and equipment when the project achieves commercial operation.

Finite-Lived Intangible Assets

Finite-lived intangible assets relate to easements and land options and mining rights. The Company amortizes finite-lived intangible assets using the straight-line method over the term of their estimated useful lives, which represents the term of the easements and land option and mining rights agreements, ranging from eleven months to twenty years. The Company periodically evaluates whether events or changes in circumstances have occurred that indicate the carrying amount of finite-lived intangible assets may not be recoverable, or information indicates that impairment may exist.

Property, Plant and Equipment

Property, plant and equipment represents the costs of completed and operational projects transferred from construction in progress, as well as land, computer equipment and software, furniture and fixtures, leasehold improvements and other equipment. Property, plant and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated using the straight-line method over the respective assets’ useful lives. Wind farms are depreciated over twenty years and the remaining assets are depreciated over two to five years. Land is not depreciated. Improvements to property, plant and equipment deemed to extend the useful economic life of an asset are capitalized. Repair and maintenance costs are expensed as incurred.

Accounting for Impairment of Long-Lived Assets

The Company periodically evaluates long-lived assets for potential impairment whenever events or changes in circumstances have occurred that indicate that impairment may exist, or the carrying amount of the long-lived asset may not be recoverable. An impairment loss is recognized only if the carrying amount of a long-lived asset is not recoverable based on its estimated future undiscounted cash flows. An impairment loss is calculated based on the excess of the carrying value of the long-lived asset over the fair value of such long-lived asset , with the fair value determined based on an estimate of discounted future cash flows. Through December 31, 2014, no impairment charges have been recorded.

Derivatives

The Company recognizes its derivative instruments as assets or liabilities at fair value in the consolidated balance sheets, unless the derivative instruments qualify for the “normal purchase normal sale” (“NPNS”) scope exception to derivative accounting. Accounting for changes in the fair value (i.e., gains or losses) of a derivative instrument depends on whether it has been designated as part of a hedging relationship and on the type of hedging relationship.

For derivative instruments that are designated as cash flow hedges, the effective portion of change in fair value of the derivative is reported as a component of other comprehensive (loss) income (“OCI”). Changes in the fair value of these derivatives are subsequently reclassified into earnings in the period that the hedged transaction affects earnings. The ineffective portion of change in fair value is recorded as a component of net (loss) income on the consolidated statement of operations. For undesignated derivative instruments, the change in fair value is reported as a component of net (loss) income on the consolidated statement of operations. Certain of our electricity price derivatives that qualify for the NPNS scope exception to derivative accounting are accounted for under the accrual method of accounting.

The Company enters into derivative transactions for the purpose of reducing exposure to fluctuations in interest rates and electricity prices. The Company has entered into interest rate swaps, an interest rate cap and an electricity price derivative.

Interest rate swaps are instruments used to fix the interest rate on variable interest rate debt.

An interest rate cap is an instrument that is used to reduce exposure to future variable interest rates when the related debt is expected to be refinanced.

The Company entered into an electricity price arrangement, which qualifies as a derivative, that fixes the price of approximately 58% of the electricity expected to be produced and sold by Gulf Wind through April 2019, and which reduces the Company’s exposure to spot electricity prices.

Deferred Financing Costs

Financing costs incurred in connection with obtaining construction and term financing are deferred and amortized over the lives of the respective loans using the effective-interest method. Amortization of deferred financing costs is capitalized during construction and recorded as interest expense in the consolidated statements of operations following commencement of commercial operation.

Income Taxes

Prior to October 2, 2013, the Company’s predecessor did not provide for income taxes as it was treated as a pass-through entity for U.S. federal and state income tax purposes, except for several specific circumstances involving its Canadian entities that are subject to Canadian income taxes, its Chilean entities, that are subject to Chilean income taxes, a U.S. entity that is subject to Puerto Rican taxes and a U.S. entity that became subject to U.S. income taxes in 2012. Federal and state income taxes were assessed at the owner level and each owner was liable for its own tax payments. Certain consolidated entities are corporations or have elected to be taxed as corporations. In these circumstances, income tax was accounted for under the asset and liability method.

Subsequent to October 2, 2013, following the Contribution Transactions, the Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company recognizes deferred tax assets to the extent that it believes these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning and results of recent operations. If the Company determines that it would be able to realize its deferred tax assets in the future in excess of their net recorded amount, it would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes. The Company records uncertain tax positions in accordance with ASC 740 on the basis of a two-step process whereby (1) it determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, it recognizes the largest amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company has a policy to classify interest and penalties associated with uncertain tax positions together with the related liability, and the expenses incurred related to such accruals, if any, are included in the provision for income taxes.

Contingent Liabilities

The Company’s contingent liabilities represent deferred and contingent obligations related to projects acquired through business combinations and contingent bonuses payable to turbine service and maintenance providers associated with long-term turbine service and maintenance arrangements. Contingent liabilities are reported at fair value at each reporting period.

Asset Retirement Obligation

The Company records asset retirement obligations for the estimated costs of decommissioning turbines, removing above-ground installations and restoring sites, at the time when a contractual decommissioning obligation materializes. The Company records accretion expense, which represents the increase in the asset retirement obligations, over the remaining or operational life of the associated wind project. Accretion expense is recorded as cost of revenue in the statement of operations using accretion rates based on credit adjusted risk-free interest rates.

Revenue Recognition

The Company sells the electricity it generates under the terms of power sale agreements (“PSAs”) or at spot-market prices. Revenue is recognized based upon the amount of electricity delivered at rates specified under the contracts, assuming all other revenue recognition criteria are met. The Company evaluates its PSAs to determine whether they are in substance leases or derivatives and, if applicable, recognizes revenue pursuant to ASC 840, Leases and ASC 815, Derivatives and Hedging, respectively. As of December 31, 2014, there were no PSAs that are accounted for as leases or derivatives and revenue is recognized on an accrual basis.

The Company also generates renewable energy credits as it produces electricity. Certain of these energy credits are sold independently in an open market and revenue is recognized at the time title to the energy credits is transferred to the buyer.

The Company acquired a ten-year energy derivative instrument as part of its acquisition of Gulf Wind in 2010, which fixes approximately 58% of the project’s expected electricity generation through April 2019. The energy derivative instrument reduces exposure to changes in commodity prices by allowing the Company to lock in a fixed price per MWh for a specified amount of annual electricity generation. The monthly settlement amounts under the energy hedge are accounted for as energy derivative settlements in the consolidated statements of operations. The change in the fair value of the energy hedge is classified as unrealized (loss) gain on energy derivative revenue in the consolidated statements of operations.

The Company recognizes revenue for warranty settlements and liquidated damages from turbine manufacturers in other revenue upon resolution of outstanding contingencies. Any cash receipts for amounts subject to future adjustment or repayment are deferred in other liabilities until the final settlement amount is considered fixed and determinable.

Cost of Revenue

The Company’s cost of revenue is comprised of direct costs of operating and maintaining its wind project facilities, including labor, turbine service arrangements, land lease royalties, depreciation, accretion, property taxes and insurance.

Stock-Based Compensation

The Company accounts for stock-based compensation related to stock options granted to employees by estimating the fair value of the stock-based awards using the Black-Scholes option-pricing model. The fair value of the stock options granted is amortized over the applicable vesting period. The Black-Scholes option pricing model includes assumptions regarding dividend yields, expected volatility, expected option term, expected forfeiture rate and risk-free interest rates. The Company estimates expected volatility based on the historical volatility of comparable publicly traded companies for a period that is equal to the expected term of the options. The risk-free interest rate is based on the U.S. treasury yield curve in effect at the time of grant for a period commensurate with the estimated expected term of the stock option. The expected term of options granted is derived using the “simplified” method as allowed under the provisions of the ASC 718, Compensation—Stock Compensation, and represents the period of time that options granted are expected to be outstanding.

The Company accounts for stock-based compensation related to restricted stock award grants by amortizing the fair value of the restricted stock award grants, which is the grant date market price, over the applicable vesting period.

Stock-based compensation expense is recorded as a component of general and administrative expenses in the Company’s consolidated statements of operations.

Comprehensive (Loss) Income

Comprehensive (loss) income consists of net (loss) income and other comprehensive (loss) income, net of tax. Other comprehensive (loss) income, net of tax included in accumulated other comprehensive (loss) income in the accompanying consolidated statements of stockholders’ equity, is comprised of changes in foreign currency translation adjustments and changes in the fair value of derivatives designated as hedges.

Segment Data

Operating segments are defined as components of a company about which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The Company’s chief operating decision maker is the chief executive officer. Based on the financial information presented to and reviewed by the chief operating decision maker in deciding how to allocate the resources and in assessing the Company’s performance, the Company has determined its wind projects represent individual operating segments with similar economic characteristics that meet the criteria for aggregation into a single reporting segment for financial statement purposes.

Recently Issued Accounting Standards

In February 2015, the Financial Accounting Standards Board (“FASB”) issued ASU 2015-02, “Consolidation: Amendments to the Consolidation Analysis” to modify the analysis that companies must perform in order to determine whether a legal entity should be consolidated. ASU 2015-02 simplifies current guidance by reducing the number of consolidation models; eliminating the risk that a reporting entity may have to consolidate based on a fee arrangement with another legal entity; placing more weight on the risk of loss in order to identify the party that has a controlling financial interest; reducing the number of instances that related party guidance needs to be applied when determining the party that has a controlling financial interest; and changing rules for companies in certain industries that ordinarily employ limited partnership or VIE structures. ASU 2015-02 is effective for public companies beginning after December 15, 2015 and interim periods within those fiscal periods. Early adoption on a modified retrospective or full retrospective basis is permitted. The Company is currently assessing the future impact of this update on its consolidated financial statements.

In November 2014, the FASB issued ASU 2014-17, “Business Combinations: Pushdown Accounting”, which provides an entity with an option to apply pushdown accounting in its separate financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity. The amendments in ASU 2014-17 are effective November 18, 2014. After the effective date, an acquired entity can make an election to apply the guidance to future change-in-control events or to its most recent change-in-control event. However, if the financial statements for the period in which the most recent change-in-control event occurred already have been issued or made available to be issued, the application of this guidance would be a change in accounting principle. The Company does not anticipate that the adoption of this update will have a material impact on its consolidated financial statements.

In November 2014, the FASB issued ASU 2014-16, “Derivatives and Hedging – Determining Whether the Host Contract in a Hybrid Financial Instrument Issued in the Form of a Share is More Akin to Debt or to Equity”, which provides clarification on how current U.S. GAAP should be interpreted in evaluating the economic characteristics and risks of a host contract in a hybrid financial instrument that is issued in the form of a share. ASU 2014-16 is effective for interim and annual periods beginning after December 15, 2015, with early adoption permitted. The Company is currently assessing the future impact of this update on its consolidated financial statements.

In August 2014, the FASB issued Accounting Standards Update (“ASU”) 2014-15, “Presentation of Financial Statements – Going Concern: Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”, which requires an entity’s management to evaluate whether there is substantial doubt about the entity’s ability to continue as a going concern and to provide related footnote disclosures. ASU 2014-15 is effective for interim and annual periods beginning after December 15, 2016, with early adoption permitted for interim and annual reporting periods for which the financial statements have not been previously issued. The Company does not anticipate that the adoption of this update will have a material impact on its consolidated financial statements.

In June 2014, the FASB issued ASU 2014-12, “Compensation – Stock Compensation” which requires an entity to treat a performance target that affects vesting that could be achieved after an employee completes the requisite service period as a performance condition. The performance target should not be reflected in estimating the grant-date fair value of the award. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attributable to the period(s) for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. ASU 2014-12 is effective for interim and annual periods beginning after December 15, 2015, with early adoption permitted either prospectively or retrospectively to all prior periods presented. The Company does not anticipate that the adoption of this update will have a material impact on its financial condition, results of operations or cash flows.

In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers”. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer, as opposed to recognizing revenue when the risks and rewards transfer to the customer under the existing revenue guidance. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. The guidance permits companies to either apply the requirements retrospectively to all prior periods presented, or apply the requirements in the year of adoption, through a cumulative adjustment. The Company is currently assessing the future impact of this update on its consolidated financial statements.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Acquisitions	3	Acquisitions
	El Arrayán Acquisition
	On June 25, 2014, the Company acquired 100% of the issued and outstanding common stock of AEI El Arrayán Chile SpA (“AEI El Arrayán”), an entity holding a 38.5% indirect interest in El Arrayán, for a total purchase price of $45.3 million, pursuant to the terms of a Stock Purchase Agreement (the “Agreement”). The Company owned a 31.5% indirect interest in El Arrayán prior to acquiring the additional 38.5% interest in order to obtain majority control (70%) of the project, as a part of its growth strategy. El Arrayán is a 115 MW wind power project company, located in Ovalle, Chile, which achieved commercial operations on June 4, 2014.
	Prior to the acquisition, the Company accounted for the investment under the equity method of accounting. Because the Company acquired an additional 38.5% indirect interest in El Arrayán, in accordance with ASC 805 Business Combinations, the acquisition was accounted for as a “business combination achieved in stages”. Accordingly, the Company remeasured the previously held equity interest in El Arrayán and adjusted it to fair value based on the Company’s existing equity interest in the fair value of the underlying assets and liabilities of El Arrayán. The fair value of the Company’s equity interest at the acquisition date was $37.0 million (31.5% of implied equity value of $117.5 million per below). The difference between the fair value of the Company’s ownership in El Arrayán and the Company’s carrying value of its investment of $19.1 million resulted in a gain of $17.9 million recorded in net gain on transactions in the consolidated statements of operations for the year ended December 31, 2014. The Company recognized additional deferred tax liability due to differences in accounting and tax bases resulting from the Company’s existing ownership interest in El Arrayán, which has been included in the consolidated statements of operations. The Company now holds a 70% controlling interest in the wind project and consolidates the accounts of El Arrayán.
	The Company acquired the assets and operating contracts for AEI El Arrayán, including assumed liabilities. The identifiable assets acquired and liabilities assumed were recorded at their fair values.
	The consolidated fair value of the assets acquired and liabilities assumed in connection with the AEI El Arrayán acquisition are as follows (in thousands):
		Consolidated
		interest
		June 25, 2014
	Cash and cash equivalents	$	713
	Trade receivables		3,829
	VAT receivable		17,031
	Prepaid expenses and other current assets		174
	Restricted cash, non-current		10,392
	Property, plant and equipment		341,417
	Intangible assets		1,121
	Net deferred tax assets		5,455
	Accounts payable and other accrued liabilities		(6,830	)
	Accrued construction costs		(9,495	)
	Accrued interest		(2,592	)
	Derivative liabilities, current		(1,942	)
	Current portion of long-term debt		(16,586	)
	Long-term debt		(209,295	)
	Derivative liabilities, non-current		(501	)
	Asset retirement obligation		(2,354	)
	Net deferred tax liabilities		(13,001	)
	Total consideration		117,536
	Less: non-controlling interest		(35,259	)
	Controlling interest	$	82,277
	Current assets, restricted cash, deferred tax assets, current liabilities, accrued construction costs, debt, accrued interest and deferred tax liabilities were recorded at carrying value, which is representative of the fair value on the date of acquisition. Derivative liabilities were recorded at fair value. Property, plant and equipment were recorded at the cost of construction plus the developer’s profit margin, which represents fair value. The asset retirement obligation was recorded at fair value using a combination of market data, operational data and discounted cash flows and was adjusted by a discount rate factor reflecting then current market conditions.
	The Company recognized deferred tax liabilities due to differences in accounting and tax bases resulting from the Company’s acquisition of incremental interest in El Arrayán and the remeasurement of the project’s remaining noncontrolling interest at fair value.
	The Company incurred $0.4 million of transaction-related expenses which were recorded in net gain on transactions in the consolidated statements of operations for the year ended December 31, 2014.
	Panhandle 1 Acquisition
	On June 30, 2014, the Company acquired 100% of the Class B membership interests in the Panhandle 1 wind project, representing a 79% initial ownership interest in the project’s distributable cash flow, through the acquisition of Panhandle Wind Holdings LLC, from Pattern Development, for a purchase price of approximately $124.4 million. The 218 MW wind project, located in Carson County, Texas, achieved commercial operations on June 25, 2014.
	Prior to the closing, certain tax equity investors made capital contributions to acquire 100% of the Class A membership interests in Panhandle 1 and have been admitted as noncontrolling members in the entity, with a 21% initial ownership interest in the project’s distributable cash flow. The Company has determined that the operating partnership agreement does not allocate economic benefits pro rata to its two classes of investors and will use the HLBV method to calculate the noncontrolling interest balance that reflects the substantive profit sharing arrangement.
	The Company acquired the assets and operating contracts for Panhandle 1, including assumed liabilities. The identifiable assets acquired and liabilities assumed were recorded at their fair values, which corresponded to the sum of the cash purchase price and the initial balance of the other investors’ noncontrolling interests.
	The consolidated fair value of the assets acquired and liabilities assumed in connection with the Panhandle 1 acquisition are as follows (in thousands):
		June 30, 2014
	Cash and cash equivalents	$	1,038
	Trade receivables		1,850
	Prepaid expenses and other current assets		71
	Restricted cash, non-current		14,293
	Property, plant and equipment		332,953
	Accounts payable and other accrued liabilities		(148	)
	Accrued construction costs		(12,806	)
	Related party payable		(44	)
	Asset retirement obligation		(2,557	)
	Total consideration before non-controlling interest		334,650
	Less: tax equity noncontrolling interest contributions		(210,250	)
	Total consideration after non-controlling interest	$	124,400
	Current assets, restricted cash, current liabilities, accrued construction costs and related party payable were recorded at carrying value, which is representative of the fair value on the date of acquisition.
	Property, plant and equipment were recorded at the cost of construction plus the developer’s profit margin, which represents fair value. The asset retirement obligation was recorded at fair value using a combination of market data, operational data and discounted cash flows and was adjusted by a discount rate factor reflecting then current market conditions.
	The Company incurred $0.5 million of transaction-related expense which was recorded in net (loss) gain on transactions in the consolidated statements of operations for the year ended December 31, 2014.
	Panhandle 2 Acquisition
	On November 10, 2014, the Company acquired 100% of the membership interests in the Panhandle 2 wind project through the acquisition of Panhandle B Member 2 LLC, from Pattern Development, for a purchase price of approximately $123.8 million.
	Subsequent to the closing, certain tax equity investors made capital contributions to acquire 100% of the Class A membership interests in Panhandle 2 and were admitted as noncontrolling members in the entity and the Company received 100% of the Class B membership interests, resulting in the tax equity investors and the Company holding initial ownership interests of 19% and 81%, respectively, in the project’s distributable cash flows. The 182 MW wind project, located in Carson County, Texas, achieved commercial operations on November 7, 2014. The Company has determined that the operating partnership agreement does not allocate economic benefits pro rata to its two classes of investors and will use the HLBV method to calculate the noncontrolling interest balance that reflects the substantive profit sharing arrangement.
	The Company acquired the assets and operating contracts for Panhandle 2, including assumed liabilities. The identifiable assets acquired and liabilities assumed were recorded at their fair values which corresponded to the sum of the cash purchase price. The short-term debt presented in the table below consists of a construction loan that was repaid in full following the acquisition.
	The consolidated fair value of the assets acquired and liabilities assumed in connection with the Panhandle 2 acquisition are as follows (in thousands):
		November 10, 2014
	Cash and cash equivalents	$	240
	Trade receivables		1,156
	Prepaid expenses and other current assets		28,997
	Property, plant and equipment		315,109
	Accrued construction costs		(24,197	)
Related party payable		(121	)
Short-term debt		(195,351	)
Asset retirement obligation		(2,003	)
Total consideration	$	123,830
Current assets, accrued construction costs and related party payable were recorded at carrying value, which is representative of the fair value on the date of acquisition. In addition, the short-term debt was recorded at carrying value, representative of the fair value, which was repaid immediately after acquisition.
Property, plant and equipment were recorded at the cost of construction plus the developer’s profit margin, which represents fair value. The asset retirement obligation was recorded at fair value using a combination of market data, operational data and discounted cash flows and was adjusted by a discount rate factor reflecting then current market conditions.
The accounting for this acquisition is preliminary. The fair value estimates for the assets acquired and liabilities assumed were based on preliminary calculations and valuations, and the estimates and assumptions are subject to change as additional information is obtained for the estimates during the measurement period (up to one year from the acquisition date). The Company incurred $0.2 million and $0.6 million of transaction-related expense which was recorded in net gain on transactions in the consolidated statements of operations for the years ended December 31, 2014 and 2013, respectively.
Logan’s Gap Acquisition
On December 19, 2014, the Company acquired 100% of the membership interests in the Logan’s Gap wind project, through the acquisition of Logan’s Gap B Member LLC, from Pattern Development, for a purchase price of approximately $15.1 million and an assumed contingent liability to a third party in the amount of $8.0 million associated with the close of construction financing and the achievement of either commercial operation or tax equity funding. The wind project is currently under construction and is located in Comanche County, Texas. The construction of the project is being financed primarily by construction debt and Pattern Energy equity. Following construction, it is expected that institutional tax equity investors will invest in the project, pursuant to an executed equity commitment agreement, so that the construction loan will be paid off such that long term financing for the project will be equity based. Upon tax equity funding, it is expected that the Company and the institutional tax equity investors will have initial ownership interests of 82% and 18%, respectively, in the project’s distributable cash flows.
The Company acquired the assets and operating contracts for Logan’s Gap, including assumed liabilities. The identifiable assets acquired and liabilities assumed were recorded at their fair values which corresponded to the sum of the cash purchase price. The consolidated fair value of the assets acquired and liabilities assumed in connection with the Logan’s Gap acquisition are as follows (in thousands):
	December 19, 2014
Cash and cash equivalents	$	2
Restricted cash, current		5,003
Prepaid expenses and other current assets		1,722
Deferred financing costs, current		2,117
Construction in progress		23,770
Property, plant and equipment		116
Other assets		80
Accrued construction costs		(4,733	)
Current portion of contingent liabilities		(7,975	)
Related party payable		(5,003	)
Total consideration	$	15,099
Current assets, current liabilities, property, plant and equipment, other assets, accrued construction costs and related party payable were recorded at carrying value, which is representative of the fair value on the date of acquisition. Construction in progress was recorded at fair value which is representative of the development effort, including the developer’s profit, and contracts acquired on the date of acquisition.
The Company recorded $8.0 million in contingent obligations, payable to a third party, at fair value upon acquisition. Of this amount, $4.0 million was paid in December 2014, upon construction financing, and the remaining $4.0 million liability is payable upon the earlier of commercial operations or tax equity funding, which is expected to occur in the fourth quarter of 2015.
The accounting for this acquisition is preliminary. The fair value estimates for the assets acquired and liabilities assumed were based on preliminary calculations and valuations, and the estimates and assumptions are subject to change as additional information is obtained for the estimates during the measurement period (up to one year from the acquisition date). The Company incurred $0.3 million of transaction-related expense which was recorded in net gain on transactions in the consolidated statements of operations for the year ended December 31, 2014.
Supplemental pro forma data (unaudited)
The unaudited pro forma statement of operations data below gives effect to the AEI El Arrayán, Panhandle 1, Panhandle 2 and Logan’s Gap acquisitions as if they had occurred on January 1, 2013. The 2014 pro forma net loss was adjusted to exclude nonrecurring transaction related expenses of $2.9 million and a nonrecurring $17.9 million gain on acquisition of El Arrayán. The unaudited pro forma data is presented for illustrative purposes only and is not intended to be indicative of actual results that would have been achieved had these acquisitions been consummated as of January 1, 2013. The unaudited pro forma data should not be considered representative of the Company’s future financial condition or results of operations.
	Year ended
	December 31,
Unaudited pro forma data (in thousands)	2014			2013
Pro forma total revenue	$	268,116		$	201,573
Pro forma total expenses		326,990			192,762
Pro forma net (loss) income		(58,874	)		8,811
Less: pro forma net loss attributable to noncontrolling interest		(8,662	)		(7,176	)
Pro forma net (loss) income attributable to controlling interest	$	(50,212	)	$	15,987
Prior to the acquisition of AEI El Arrayán, net loss was recorded in equity in (losses) earnings in unconsolidated investments in the consolidated statement of operations. From January 1, 2014 to June 25, 2014, the Company recorded net loss of $0.4 million in equity in (losses) earnings on unconsolidated investments related to El Arrayán.
The following table presents the amounts included in the consolidated statements of operations for AEI El Arrayán, Panhandle 1, Panhandle 2 and Logan’s Gap since their respective dates of acquisition:
	Year ended
	December 31,
Unaudited data (in thousands)	2014
Total revenue	$	30,841
Total expenses		41,232
Net loss		(10,391	)
Less: net loss attributable to noncontrolling interest		(6,673	)
Net loss attributable to controlling interest	$	(3,718	)

Prepaid_expenses_and_other_cur

Prepaid expenses and other current assets	12 Months Ended
	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses and other current assets	4	Prepaid expenses and other current assets
	The following table presents the components of prepaid expenses and other current assets (in thousands):
		December 31,
		2014		2013
	Prepaid expenses	$	15,275	$	10,132
	Prepaid construction costs		5,155		—
	Sales tax		786		50
	Other current assets:
	Deposit for letters of credit		3,425		—
	Deferred equity issuance costs		2,331		—
	Other		982		1,233
	Prepaid expenses and other current assets	$	27,954	$	11,415

Property_Plant_and_Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	5	Property, Plant and Equipment
	The following presents the categories within property, plant and equipment (in thousands):
		December 31,
		2014			2013
	Operating wind farms	$	2,624,640		$	1,652,119
	Furniture, fixtures and equipment		4,366			3,785
	Land		141			16
	Subtotal		2,629,147			1,655,920
	Less: accumulated depreciation		(278,291	)		(179,778	)
	Property, plant and equipment, net	$	2,350,856		$	1,476,142
	The Company recorded depreciation expense related to property, plant and equipment of $102.9 million, $82.0 million and $48.3 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	In June 2013, the Company received $115.9 million and $57.6 million, from the U.S. Department of the Treasury, for Ocotillo and Santa Isabel, respectively, under a cash grant in lieu of investment tax credit (“Cash Grant”). In December 2012, the Company received $79.9 million for Spring Valley under a Cash Grant from the U.S. Department of the Treasury. The Company recorded the cash proceeds as a deduction from the carrying amount of the related wind farm assets which resulted in the assets being recorded at lower amounts.
	The Cash Grants received for Ocotillo, Santa Isabel, and Spring Valley reduced depreciation expense recorded in the consolidated statements of operations by approximately $12.7 million, $13.0 million and $1.5 million for the years ended December 31, 2014, 2013 and 2012, respectively.

Unconsolidated_Investments

Unconsolidated Investments	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Unconsolidated Investments	6	Unconsolidated Investments
	The following presents projects that are accounted for under the equity method of accounting (in thousands):
								Percentage of Ownership
		December 31,						December 31,
		2014			2013			2014			2013
	South Kent	$	17,360		$	59,488			50	%		50	%
	Grand		11,719			26,464			45	%		45	%
	El Arrayán		—			21,103			N/A			31.5	%
	Unconsolidated investments	$	29,079		$	107,055
	South Kent
	The Company is a noncontrolling investor in a joint venture established to develop, construct, and own a wind power project located in Ontario, Canada. The project has a 20-year PPA and commenced commercial operations on March 28, 2014.
	Grand
	On December 20, 2013, the Company acquired from Pattern Development a 45% equity interest in Grand for $79.5 million, plus a contingent payment of up to C$5.0 million, or $4.3 million based on the exchange rate as of December 31, 2014, as calculated based on final budget to actual amounts and distributions payable upon term conversion which has been updated from the Company’s original estimate to 2015. Grand is a joint venture established to develop, construct, and own a wind power project located in Ontario, Canada. The project has a 20-year PPA and commenced commercial operations on December 9, 2014. The Company’s investment in Grand was paid from general corporate funds. The Company is a noncontrolling investor in Grand and the investment is accounted for under the equity method of accounting.
	El Arrayán
	On June 25, 2014, the Company increased its total ownership interest in El Arrayán to 70%. See Note 3, Acquisitions, for disclosure on the acquisition of El Arrayán. As such, the Company has consolidated the operations of El Arrayán as of the acquisition date and is no longer accounting for this investment under the equity method of accounting.
	The following summarizes the aggregated balance sheets of El Arrayán as of December 31, 2014 and 2013, and its operating results for the period from January 1, 2014 to June 25, 2014 and the years ended December 31, 2013 and 2012, respectively (in thousands):
		December 31,
		2014			2013
	Current assets	$	—		$	16,362
	Non-current assets		—			260,187
	Total assets	$	—		$	276,549
	Current liabilities	$	—		$	9,224
	Non-current liabilities		—			197,597
	Total liabilities		—			206,821
	Total equity		—			69,728
	Total liabilities and equity	$	—		$	276,549
		December 31,
		2014			2013			2012
	Revenue	$	1,821		$	—		$	—
	Other (income) expense		3,083			941			384
	Net loss	$	(1,262	)	$	(941	)	$	(384	)

Accounts_payable_and_other_acc

Accounts payable and other accrued liabilities	12 Months Ended
	Dec. 31, 2014
Payables and Accruals [Abstract]
Accounts payable and other accrued liabilities	7	Accounts payable and other accrued liabilities
	The following table presents the components of accounts payable and other accrued liabilities (in thousands):
		December 31,
		2014		2013
	Accounts payable	$	673	$	168
	Other accrued liabilities		9,202		6,329
	Warranty settlement payments		639		2,187
	LTSA upgrades liability		680		—
	Land lease rent payable		2,115		953
	Payroll liabilities		4,453		2,162
	Property tax payable		4,625		3,490
	Sales tax payable		2,406		261
	Accounts payable and other accrued liabilities	$	24,793	$	15,550

Long_term_debt

Long term debt	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Long term debt	8	Long term debt
	The Company’s long term debt as of December 31, 2014 and 2013 is presented below (in thousands):
		December 31,						Interest Rate as of						Interest
								December 31,						Type
		2014			2013			2014			2013				Maturity
	Hatchet Ridge term loan	$	228,288		$	239,865			1.43	%		1.43	%	Imputed	December 2032
	Gulf Wind term loan		156,122			166,448			3.23	%		3.25	%	Variable	Mar-20
	St. Joseph term loan		189,472			215,330			5.88	%		5.88	%	Fixed	May-31
	Spring Valley term loan		167,261			173,110			2.62	%		2.63	%	Variable	Jun-30
	Santa Isabel term loan		112,609			115,721			4.57	%		4.57	%	Fixed	September 2033
	El Arrayan commercial term loan		99,665			—			2.92	%		N/A		Variable	Mar-29
	El Arrayan EKF term loan		109,630			—			5.56	%		N/A		Fixed	Mar-29
	Ocotillo commercial term loan		222,175			230,944			1.98	%		3	%	Variable	Aug-20
	Ocotillo development term loan		106,700			107,800			2.33	%		2.35	%	Variable	Aug-33
	Logan’s Gap construction loan		58,691			—			1.64	%		N/A		Variable	Dec-15
			1,450,613			1,249,218
	Less: current portion		(121,561	)		(48,851	)
		$	1,329,052		$	1,200,367
	The following are principal payments due under long-term debt as of December 31, 2014 (in thousands):
	For the year ending December 31,
	2015	$	121,561
	2016		65,877
	2017		67,277
	2018		72,750
	2019		83,613
	Thereafter		1,039,535
		$	1,450,613
	Interest and commitment fees incurred, and interest expense recorded in the Company’s consolidated statements of operations are as follows (in thousands):
		Year ended December 31,
		2014			2013			2012
	Interest and commitment fees incurred	$	59,864		$	57,478		$	43,496
	Capitalized interest, commitment fees, and letter of credit fees		(2,856	)		(4,210	)		(10,259	)
	Letter of credit fees		4,377			3,530			720
	Amortization of financing costs		6,309			6,816			2,545
	Interest expense	$	67,694		$	63,614		$	36,502
	Hatchet Ridge
	In December 2010, Hatchet Ridge entered into sale-leaseback transactions to finance the facility for 22 years. In accordance with ASC 840, Leases, Hatchet Ridge accounts for the sale-leaseback as a financing transaction.
	Collateral for the sale-leaseback financing includes Hatchet Ridge’s tangible assets and contractual rights and cash on deposit with the depository agent. Its loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict Hatchet Ridge’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
	Gulf Wind
	The Company acquired Gulf Wind in March 2010. Concurrent with its acquisition, Gulf Wind entered into a $195.4 million credit facility. The Gulf Wind credit facility has a term of ten years. In connection with the facility, Gulf Wind entered into interest rate swaps and cap agreements to reduce its exposure to variable interest rates of the term of the facility and to hedge its exposure to re-financing rate risk.
	Collateral for the Gulf Wind credit facility includes Gulf Wind’s tangible assets and contractual rights and cash on deposit with the depository agent. Its loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict Gulf Wind’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
	St. Joseph
	In March 2010, St. Joseph entered into a C$250.0 million construction and term loan facility that was converted to a 20-year term loan in May 2011.
	Collateral for the St. Joseph facility includes St. Joseph’s tangible assets and contractual rights and cash on deposit with the depository agent. Its loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict St. Joseph’s ability to incur debt, grant liens, sell or lease certain assets, transfer equity interests, dissolve, make distributions and change its business.
	Spring Valley
	In August 2011, Spring Valley entered into a $178.9 million construction loan facility and a $53.3 million cash grant bridge loan. Spring Valley reached commercial operations on August 16, 2012 and the construction loan was converted to a term loan on November 16, 2012. The cash grant bridge loan was repaid in December 2012 from funds the Company received under a Cash Grant from the U.S. Department of Treasury following the wind project being placed in service. In connection with the term loan, Spring Valley entered into interest rate swaps for the term of the loan to hedge its exposure to variable interest rates following term conversion of the facility.
	Collateral for the loan consists of Spring Valley’s tangible assets and contractual rights, and cash on deposit with the depository agent. Its loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict Spring Valley’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
	Santa Isabel
	In October 2011, Santa Isabel entered into a $119.0 million construction loan facility and a $57.5 million cash grant bridge loan facility. On December 5, 2012, Santa Isabel achieved commercial operations under the terms of its PPA. The construction loan converted to a term loan on May 15, 2013 and matures on September 30, 2033. The cash grant bridge loan was repaid from funds the Company received under a Cash Grant in May 2013.
	Collateral for the Santa Isabel facility consists of Santa Isabel’s tangible assets and contractual rights, and cash on deposit with the depository agent. Its loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict Santa Isabel’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
	Ocotillo
	In October 2012, Ocotillo entered into a $467.3 million financing agreement comprised of two construction loan facilities totaling $351.5 million, a network upgrade bridge loan facility of $56.6 million and a letter of credit facility of $59.2 million. The two loan facilities consist of a development bank tranche of $110.0 million and a commercial bank tranche of $241.5 million. Ocotillo reached full commercial operations in July 2013, and the two construction loans converted to term loans on September 20, 2013 and mature 20 years and 7 years after the term loan conversion, respectively. The network upgrade bridge loan was repaid in August 2013 from reimbursements received from the utility related to the construction of network upgrade costs. In connection with the financing agreement, the Company entered into interest rate swaps on 90% of the loan commitment. In addition, in September 2013, Ocotillo prepaid $2.2 million of the development bank loan and $5.3 million of the commercial bank loan pursuant to a proposal initiated by Ocotillo and accepted by the lenders. In October 2014, the financing agreement was amended to include a margin rate decrease of 1.0% for the commercial bank tranche.
	Collateral under the Ocotillo financing agreement consists of Ocotillo’s tangible assets and contractual rights, and cash on deposit with the depository agent. Its loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict Ocotillo’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
	El Arrayán
	In May 2012, El Arrayán entered into a first lien senior secured credit agreement (“El Arrayán Credit Agreement”) which provides up to approximately $225.0 million in borrowings. Borrowings under the El Arrayán Credit Agreement were used to finance the construction of the El Arrayán wind project and are comprised of a commercial tranche of up to $100.0 million and an export credit agency tranche provided by Eksport Kredit Fonden of Denmark (“EKF Tranche”) of up to $110.0 million, and letter of credit facility in an amount of up to $15.0 million. In connection with the El Arrayán Credit Agreement, the Company entered into interest rate swaps on 95.8% of the commercial tranche term loan. The project commenced commercial operations in June 2014 and the construction loan converted into term loans on August 14, 2014. The financing is non-recourse to El Arrayán.
	The commercial tranche loan is a LIBOR loan and accrues interest at LIBOR plus 2.75% per annum from the closing until the sixth anniversary of closing, 3.00% from the sixth anniversary to the tenth anniversary of closing, 3.25% from the tenth anniversary to the fourteenth anniversary of closing, and 3.50% after the fourteenth anniversary of closing. The EKF Tranche term loan accrues interest at a fixed rate of 5.56%, in each case, plus a margin of 0.25% from the sixth anniversary to the tenth anniversary of the closing, 0.50% from the tenth anniversary to the fourteenth anniversary of closing, and 0.75% after the fourteenth anniversary of closing.
	El Arrayán—Value Added Tax (VAT) Facility
	In addition to the El Arrayán Credit Agreement, in May 2012, El Arrayán entered into a $20.0 million VAT facility with Corpbanca. Under the VAT facility El Arrayán may borrow funds to pay for VAT payments due from the project. The last day to borrow funds under the VAT facility was November 3, 2014. The VAT facility has an interest rate of Chilean Interbank Rate plus 1.00% and terminates in November 2015. El Arrayán is also required to pay a commitment fee on the undrawn portion of the VAT facility. As of December 31, 2014, the outstanding balance on the VAT facility was $2.0 million.
	Logan’s Gap
	In December 2014, Logan’s Gap entered into a $282.8 million financing agreement comprised of a $247.1 million construction loan and letter of credit facilities to provide letter of credit loans in an amount totaling up to $35.7 million. Under the financing agreement, the scheduled maturity date is December 31, 2015 (which date may be extended to March 31, 2016, subject to certain conditions), at which time the loans will be repaid from capital contributions from equity investors and the letters of credit terminated. Pursuant to a Letter of Credit and Reimbursement Agreement, a commercial bank will then issue a letter of credit up to $15.0 million in favor of the project’s hedge counterparty.
	Collateral under the Logan’s Gap financing agreement consists of Logan’s Gap tangible assets and contractual rights, and cash on deposit with the depository agent. The loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict Logan’s Gap’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
	Revolving Credit Facility
	On November 15, 2012, the Company entered into a $120.0 million revolving credit agreement (“Existing Credit Agreement”) for working capital with a four-year term comprised of a revolving loan facility and a letter of credit facility. The revolving credit agreement has an “accordion feature” under which the Company has the right to increase available borrowings by up to $35.0 million if its lenders or other additional lenders are willing to lend on the same terms and meet certain other conditions.
	Collateral for the revolving credit facility consists of the Company’s membership interests in certain of the Company’s holding company subsidiaries. The revolving credit facility contains a broad range of covenants that, subject to certain exceptions, restrict the Company’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.
In March 2014, the Company exercised the accordion feature by increasing available borrowings by an additional $25.0 million, resulting in an aggregate facility amount of $145.0 million. Simultaneously, the Ocotillo project was added to the collateral pool that supports the revolving credit facility.
In December 2014, the Company entered into an Amended and Restated Credit and Guaranty Agreement which increased the available borrowings under the Existing Credit Agreement from $145 million to $350.0 million. Simultaneously, the Panhandle 1, Panhandle 2, South Kent and Grand projects were added to the collateral pool that supports the revolving credit facility.
As of December 31, 2014 and 2013, letters of credit of $45.1 million and $44.8 million, respectively, have been issued and loans of $50.0 million and $56.0 were drawn in 2014 and 2013, respectively. As of December 31, 2014, the outstanding balance on the revolving credit facility is $50.0 million. There was no outstanding balance on the revolving credit facility in the prior year.
Loans, when and if drawn, are either base rate loans or Eurodollar rate loans. The base rate loans accrue interest at the fluctuating rate per annum equal to the greatest of the (i) the prime rate, (ii) the federal funds rate plus 0.50% and (iii) the Eurodollar rate that would be in effect for a Eurodollar rate loan with an interest period of one month plus 1.0%, plus an applicable margin ranging from 1.25% to 1.75%. The Eurodollar rate loans accrue interest at a rate per annum equal to LIBOR, plus an applicable margin ranging from 2.25% to 2.75%. Under the facility, the Company is required to pay a revolving commitment fee equal to the average of the daily difference between revolving commitments and the total utilization of revolving commitments times 0.50%. In addition, the Company is required to pay letter of credit fees. The facility is secured by pledges of the capital stock and ownership interests in certain of the Company’s holding company subsidiaries. The revolving credit facility contains a broad range of covenants that, subject to certain exceptions, restrict the Company’s ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business.

Asset_Retirement_Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	9	Asset Retirement Obligations
	The Company’s asset retirement obligations represent the estimated cost of decommissioning the turbines, removing above-ground installations and restoring the sites at a date that is 20 years from the commencement of commercial operation of the facility.
	The following table presents a reconciliation of the beginning and ending aggregate carrying amounts of asset retirement obligations as of December 31, 2014, 2013 and 2012 (in thousands):
		December 31,
		2014			2013			2012
	Beginning asset retirement obligations	$	20,834		$	19,056		$	10,342
	Additions during the year		7,195			767			7,971
	Foreign currency translation adjustment		(228	)		(172	)		59
	Accretion expense		1,471			1,183			684
	Ending asset retirement obligations	$	29,272		$	20,834		$	19,056

Derivative_Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	10	Derivative Instruments
	The Company employs a variety of derivative instruments to manage its exposure to fluctuations in interest rates and electricity prices. The following tables present the amounts that are recorded in the Company’s consolidated balance sheets as of December 31, 2014, 2013 and 2012 (in thousands):
	Undesignated Derivative Instruments Classified as Assets (Liabilities):
					As of						Year ended
					Fair Market Value						YTD Gain (Loss)
	Derivative Type	Project	Quantity	Maturity	Current			Long-Term			Recognized into
				Dates	Portion			Portion			Income
	December 31, 2014
	Interest rate swaps	Ocotillo	6	6/30/30	$	(3,403	)	$	2,523		$	(11,339	)
	Interest rate cap	Gulf Wind	1	12/31/24		—			352			(329	)
	Energy derivative	Gulf Wind	1	4/30/19		18,506			45,969			(3,878	)
					$	15,103		$	48,844		$	(15,546	)
	December 31, 2013
	Interest rate swaps	Ocotillo	6	6/30/30	$	(3,899	)	$	14,358		$	15,367
	Interest rate cap	Gulf Wind	1	12/31/24		—			681			234
	Energy derivative	Gulf Wind	1	4/30/19		13,937			54,416			(11,272	)
					$	10,038		$	69,455		$	4,329
	December 31, 2012
	Interest rate swaps	Ocotillo	6	6/30/30	$	(1,980	)	$	(2,931	)	$	(4,909	)
	Interest rate cap	Gulf Wind	1	12/31/24		—			447			(44	)
	Energy derivative	Gulf Wind	1	4/30/19		17,177			62,448			(6,951	)
					$	15,197		$	59,964		$	(11,904	)
	Designated Derivative Instruments Classified as Assets (Liabilities):
					As of						Year ended
					Fair Market Value						YTD Gain (Loss)
	Derivative Type	Project	Quantity	Maturity	Current			Long-Term			Recognized in
				Dates	Portion			Portion			OCI
	December 31, 2014
	Interest rate swaps	Ocotillo	6	6/30/33	$	(1,917	)	$	525		$	(8,912	)
	Interest rate swaps	El Arrayan	3	3/31/32		(1,822	)		(3,338	)		(1,983	)
	Interest rate swaps	Gulf Wind	7	3/15/20		(4,719	)		(6,915	)		1,094
	Interest rate swaps	Spring Valley	2	6/28/30		(4,446	)		(7,214	)		(9,869	)
					$	(12,904	)	$	(16,942	)	$	(19,670	)
	December 31, 2013
	Interest rate swaps	Ocotillo	6	6/30/33	$	(2,105	)	$	9,625		$	10,434
	Interest rate swaps	Gulf Wind	7	3/15/20		(5,289	)		(7,439	)		9,398
	Interest rate swaps	Spring Valley	2	6/28/30		(4,878	)		3,087			17,043
					$	(12,272	)	$	5,273		$	36,875
	December 31, 2012
	Interest rate swaps	Ocotillo	6	6/30/33	$	(952	)	$	(1,962	)	$	(2,914	)
	Interest rate swaps	Gulf Wind	7	3/15/20		(5,558	)		(16,568	)		(1,835	)
	Interest rate swaps	Spring Valley	2	6/28/30		(4,972	)		(13,865	)		(6,421	)
					$	(11,482	)	$	(32,395	)	$	(11,170	)
	Gulf Wind
	In 2010, Gulf Wind entered into interest rate swaps with each of its lenders to manage exposure to interest rate risk on its long-term debt. The interest rate swaps exchange variable interest rate payments for fixed interest rate payments that were approximately 6.6% for the years ended December 31, 2014, 2013 and 2012. The fixed interest rate is set at 6.6% for years two through eight and 7.1% and 7.6% for the last two years of the loan term, respectively. The interest rate swaps qualify for hedge accounting and were designated as cash flow hedges. No ineffectiveness was recorded for the years ended December 31, 2014, 2013 and 2012. The Company reclassified $5.5 million, $5.7 million and $5.7 million related to cash settlements into earnings from accumulated other comprehensive loss during the years ended December 31, 2014, 2013 and 2012, respectively.
	In 2010, Gulf Wind also entered into an interest rate cap to manage exposure to future interest rates when its long-term debt is expected to be refinanced at the end of the ten-year term. The cap protects the Company if future interest rates exceed approximately 6.0%. The cap has an effective date of March 31, 2020, terminates on December 31, 2024, and has a notional amount of $42.1 million which reduced quarterly during its term. The cap is a derivative but does not qualify for hedge accounting and has not been designated. The Company recognized unrealized (losses) gains of ($0.3) million, $0.2 million and $0 for the years ended December 31, 2014, 2013 and 2012, respectively, in unrealized (loss) gain on derivatives in the consolidated statements of operations. The derivative instrument’s asset value as of December 31, 2014, 2013 and 2012, was approximately $0.4 million, $0.7 million and $0.4 million, respectively.
	In 2010, Gulf Wind acquired an energy derivative instrument to manage its exposure to variable electricity prices. The energy price swap fixes the price of approximately 58% of its electricity generation through April 2019. The energy derivative instrument is a derivative but did not meet the criteria required to adopt hedge accounting. The energy derivative instrument’s fair value as of December 31, 2014, 2013 and 2012 was $64.5 million, $68.4 million and $79.6 million, respectively. Gulf Wind recognized unrealized losses of $3.9 million, $11.3 million, and $7.0 million for the years ended December 31, 2014, 2013 and 2012, respectively, reported in unrealized loss on energy derivative in the consolidated statements of operations.
	Spring Valley
	In 2011, Spring Valley entered into interest rate swaps with its lenders to manage exposure to interest rate risk on its long-term debt. The interest rate swaps exchange variable interest rate payments for fixed interest rate payments of approximately 5.5% for the first four years of its term debt and increases by 0.25% every four years, thereafter. The interest rate swaps qualified for hedge accounting and were designated as cash flow hedges. No ineffectiveness was recorded for the years ended December 31, 2014, 2013 and 2012. The Company reclassified $5.0 million, $5.1 million and $0 related to cash settlements into earnings from accumulated other comprehensive loss during the years ended December 31, 2014, 2013 and 2012, respectively.
	Ocotill
	In October 2012, Ocotillo entered into interest rate swaps with its lenders to manage exposure to interest rate risk on its long-term debt. The interest rate swaps exchange variable interest rate payments for fixed interest rate payments of approximately 2.5% and 2.2% for the development bank term loans and the commercial bank term loans, respectively. The interest rate swaps for the development bank loans qualify for hedge accounting and were designated as cash flow hedges. No ineffectiveness was recorded for the years ended December 31, 2014, 2013 and 2012. The Company reclassified $2.2 million, $1.1 million and $0 into earnings from accumulated other comprehensive (loss) income, for the years ended December 31, 2014, 2013 and 2012, respectively, as quarterly hedge payments occur. The interest rate swaps for the commercial bank loans are undesignated derivatives that are used to mitigate exposure to variable interest rate debt. The Company recognized unrealized (losses) gains of ($11.3) million, $15.4 million and ($4.9) million for the years ended December 31, 2014, 2013 and 2012, respectively, in unrealized (loss) gain on derivatives in the consolidated statements of operations.
	El Arrayán
	In May 2012, El Arrayán entered into three interest rate swap agreements with its lenders to manage exposure to interest rate risk on its long term debt. The interest rate swaps exchange variable interest rate payments for fixed interest rate payments of approximately 3.4% for the first two years of its term debt and subsequently increased to 5.8%, and increases by 0.25% on every fourth anniversary of the closing date, thereafter. The interest rate swaps qualify for hedge accounting and were designated as cash flow hedges. No ineffectiveness was recorded for the year ended December 31, 2014. The Company reclassified $1.1 million, $0, and $0 related to cash settlements into earnings from accumulated other comprehensive loss, net of tax impact of $0.4 million, $0, and $0 during the years ended December 31, 2014, 2013 and 2012, respectively.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive (Loss) Income	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Accumulated Other Comprehensive (Loss) Income	11	Accumulated Other Comprehensive (Loss) Income
	The following table summarizes changes in the accumulated other comprehensive (loss) income balance by component:
					Effective Portion of			Proportionate
		Foreign			Change in Fair Value			Share of Equity
		Currency			of Derivatives			Investee’s OCI			Total
	Balances at January 1, 2012	$	(2,903	)	$	(32,707	)	$	—		$	(35,610	)
	Net current period other comprehensive income (loss)		2,749			(11,170	)		(1,475	)		(9,896	)
	Balances at December 31, 2012		(154	)		(43,877	)		(1,475	)		(45,506	)
	Net current period other comprehensive (loss) income		(8,309	)		36,875			2,473			31,039
	Grand acquisition		—			—			(2,910	)		(2,910	)
	Balances at December 31, 2013		(8,463	)		(7,002	)		(1,912	)		(17,377	)
	Net current period other comprehensive (loss) income		(10,875	)		(19,670	)		(5,991	)		(36,536	)
	Balances at December 31, 2014	$	(19,338	)	$	(26,672	)	$	(7,903	)	$	(53,913	)

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair Value Measurements	12	Fair Value Measurements
	The Company’s fair value measurements incorporate various factors, including the credit standing and performance risk of the counterparties, the applicable exit market, and specific risks inherent in the instrument. Nonperformance and credit risk adjustments on risk management instruments are based on current market inputs when available, such as credit default hedge spreads. When such information is not available, internal models may be used.
	Assets and liabilities recorded at fair value in the consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. Hierarchical levels directly related to the amount of subjectivity associated with the inputs to valuation of these assets or liabilities are as follows:
	Level 1—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.
	Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.
	Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities and which reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuations technique and the risk inherent in the inputs to the model.
	Short-term Financial Instruments
	Short-term financial instruments consist principally of cash, cash equivalents, accounts receivable, accounts payable, other accrued liabilities and contingent liabilities. Based on the nature and short maturity of these instruments their fair value is approximated using carrying cost and they are presented in the Company’s financial statements at carrying cost. The fair values of cash, cash equivalents and restricted cash are classified as Level 1 in the fair value hierarchy. The fair values of accounts receivable, accounts payable, other accrued liabilities and contingent liabilities are classified as Level 2 in the fair value hierarchy.
	Financial Instruments Measured at Fair Value on a Recurring Basis
	The Company’s financial assets and (liabilities) which require fair value measurement on a recurring basis are classified within the fair value hierarchy as follows (in thousands):
		Fair Value
		Level 1			Level 2			Level 3			Total
	December 31, 2014
	Interest rate swaps	$	—		$	(30,726	)	$	—		$	(30,726	)
	Interest rate cap		—			352			—			352
	Energy derivative		—			—			64,475			64,475
		$	—		$	(30,374	)	$	64,475		$	34,101
	December 31, 2013
	Interest rate swaps	$	—		$	3,460		$	—		$	3,460
	Interest rate cap		—			681			—			681
	Energy derivative		—			—			68,353			68,353
		$	—		$	4,141		$	68,353		$	72,494
	Level 2 Inputs
	Derivative instruments subject to re-measurement are presented in the financial statements at fair value. The interest rate swaps and interest rate cap were valued by discounting the net cash flows using the forward LIBOR curve with the valuations adjusted by the Company’s credit default hedge rate. There were no transfers between Level 1 and Level 2 during the periods presented.
	Level 3 Inputs
	The fair value of the contingent liabilities is based upon the time of realization and the probability of the contingent event. An unobservable discount rate of 7% is used to determine the present value of the contractual liabilities and an unobservable probability factor of 75% was assigned to the contingent event prior to realization after considering contract terms, land rights, interconnect network, and environmental permits. The significant primary unobservable input used for contingent liabilities is the probability factor. Significant increases or decreases in this unobservable input would result in a significantly lower or higher fair value measurement.
	The energy derivative instrument was valued by discounting the projected net cash flows over the remaining life of the derivative instrument using forward energy curves adjusted by a nonperformance risk factor. The significant unobservable input in calculating the fair value of the energy derivative instrument is forward electricity prices, which are derived from and impacted by changes in forward natural gas prices. Significant increases or decreases in this unobservable input would result in a significantly lower or higher fair value measurement.
	The following table presents a reconciliation of contingent liabilities and the energy derivative contract measured at fair value, in thousands, on a recurring basis using significant unobservable inputs for the years ended December 31, 2014, 2013 and 2012, respectively. There were no transfers between Level 2 and Level 3 during the periods presented.
		Contingent			Energy			Total
		Liabilities			Derivative
	Balance at December 31, 2011	$	(5,986	)	$	86,577		$	80,591
	Settlements		—			(19,644	)		(19,644	)
	Change in fair value, net of settlements		(2,015	)		12,692			10,677
	Balances at December 31, 2012		(8,001	)		79,625			71,624
	Settlements		8,001			(16,798	)		(8,797	)
	Change in fair value, net of settlements		—			5,526			5,526
	Balances at December 31, 2013		—			68,353			68,353
	Settlements		—			(13,524	)		(13,524	)
	Change in fair value, net of settlements		—			9,646			9,646
	Balances at December 31, 2014	$	—		$	64,475		$	64,475
	During the years ended December 31, 2014, 2013 and 2012, the Company recognized unrealized losses on energy derivative of $3.9 million, $11.3 million, and $7.0 million, respectively.
	Financial Instruments not Measured at Fair Value
	The following table presents the carrying amount and fair value, in thousands, and the fair value hierarchy of the Company’s financial liabilities that are not measured at fair value in the consolidated balance sheets as of December 31, 2014 and 2013, but for which fair value is disclosed.
		As reflected on			Fair Value
		the balance sheet			Level 1			Level 2			Level 3			Total
	31-Dec-14
	Long-term debt, including current portion	$	1,450,613		$	—		$	1,416,744		$	—		$	1,416,744
	31-Dec-13
	Long-term debt, including current portion	$	1,249,218		$	—		$	1,165,119		$	—		$	1,165,119
	Long term debt is presented on the consolidated balance sheet at amortized cost. The fair value of variable interest rate long-term debt is approximated by its carrying cost. The fair value of fixed interest rate long-term debt is estimated based on observable market prices or parameters or derived from such prices or parameters. Where observable prices or inputs are not available, valuation models are applied, using the net present value of cash flow streams over the term using estimated market rates for similar instruments and remaining terms.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	13	Income Taxes
	The following table presents significant components of the provision for income taxes (in thousands):
		Year ended December 31,
		2014			2013			2012
	Current:
	Federal	$	—		$	—		$	—
	State		—			—			—
	Foreign		182			—			—
	Total current expense (benefit)		182			—			—
	Deferred:
	Federal		—			2,961			—
	State		—			—			—
	Foreign		2,954			1,585			(3,604	)
	Total deferred expense (benefit)		2,954			4,546			(3,604	)
	Total provision for income taxes	$	3,136		$	4,546		$	(3,604	)
	The following table presents the domestic and foreign components of net income (loss) before income tax (benefit) expense (in thousands):
		Year ended December 31,
		2014			2013			2012
	U.S.	$	(34,788	)	$	4,022		$	(17,810	)
	Foreign		(2,075	)		10,596			830
	Total	$	(36,863	)	$	14,618		$	(16,980	)
	The following table presents a reconciliation of the statutory U.S. federal income tax rate to the Company’s effective tax rate, as a percentage of income before taxes for the years ended December 31, 2014, 2013 and 2012:
		Year ended
		December 31,
		2014			2013			2012
	Computed tax at statutory rate		35	%		35	%		35	%
	Book/tax basis difference		—			—			27.2	%
	Partnership income not subject to taxes		—			—			(40.9	%)
	Adjustment for income in non-taxable entities allocable to noncontrolling interest		(7.6	%)		16.5	%		—
	Foreign rate differential		—			—			—
	Tax rate differential on pre-tax book income, other		5.6	%		2.1	%		—
	Local tax on branch profits/(losses)—Puerto Rico		1.6	%		13.1	%		—
	Permanent book/tax differences (domestic only)		(0.1	%)		(2.2	%)		—
	Valuation Allowance		(33.4	%)		187.2	%		—
	Deferred tax liability on Chilean shareholder liability due to tax regime change		(3.6	%)		—			—
	Change in tax rate due to change in Chilean tax regime		(6.2	%)		—			—
	Other		0.1	%		3.1	%		—
	ARRA Section 1603 grant-basis reduction deferred tax assets		—			(223.7	%)		—
	Effective income tax rate		(8.6	%)		31.1	%		21.3	%
	The following table presents significant components of the Company’s deferred tax assets and deferred tax liabilities as of December 31, 2014 and 2013 (in thousands):
		Year ended December 31,
		2014			2013			2012
	Deferred tax assets/(liabilities)—current:
	Accruals, prepaids and other current deferred tax assets and liabilities	$	(344	)	$	2,399		$	—
	Basis difference in derivatives		4,779			2,835			—
	Total gross deferred tax assets/(liabilities)		4,435			5,234			—
	Less: valuation allowance		(4,266	)		(4,661	)		—
	Total net deferred tax assets/(liabilities)—current	$	169		$	573		$	—
	Deferred tax assets/(liabilities)—non-current:
	Property, plant and equipment	$	(104,767	)	$	(36,548	)	$	(47,894	)
	Basis difference in foreign subsidiaries		37,626			40,097			—
	Partnership interest		994			(4,917	)		—
	Lease Hatchet Ridge		28,044			29,314			—
	Asset retirement obligation		5,216			4,649			—
	Equity method		—			3,794			—
	Unrealized loss on derivatives		—			(5,830	)		—
	Other temp differences		256			—
	Net operating loss carryforwards		130,248			61,441			45,302
	Other non current deferred tax assets and liabilities		(5,081	)		(4,595	)		(690	)
	Change in tax status		—			—			4,599
	Accruals not currently deductible		—			—			443
	Total gross deferred tax assets/(liabilities)—non-current		92,536			87,405			1,760
	Less: valuation allowance		(107,480	)		(95,318	)		(482	)
	Total net deferred tax assets/(liabilities)—non-current	$	(14,944	)	$	(7,913	)	$	1,278
Total net deferred tax assets/(liabilities)	$	(14,775	)	$	(7,340	)	$	1,278
The deferred tax assets and deferred tax liabilities resulted primarily from temporary differences between book and tax basis of assets and liabilities. The Company regularly assesses the likelihood that future taxable income levels will be sufficient to ultimately realize the tax benefits of the deferred tax assets. Should the Company determine that future realization of the tax benefits is not more likely than not, additional valuation allowance would be established which would increase the Company’s tax provision in the period of such determination. The net deferred tax assets and net deferred tax liabilities as of December 31, 2014 and 2013 are attributed primarily to the Company’s Canadian, Puerto Rican and Chilean entities. The net change in valuation allowance increased by $11.8 million and $99.5 million during the years ended December 31, 2014 and December 31, 2013, respectively.
As of December 31, 2014, the Company had U.S federal and state net operating loss carryforwards in the amount of $225.6 million and $25.5 million, respectively. These net operating loss carryforwards are available to reduce future taxable income and will begin to expire commencing in 2032 for federal and state purposes.
Internal Revenue Code Section 382 places a limitation ( the “Section 382 Limitation”) on the amount of taxable income that can be offset by net operating loss (“NOL”) and credit carryforwards, as well as built-in loss items, after a change in control (generally greater than 50% change in ownership) of a loss corporation. California has similar rules. The Company did not have any historic U.S. net operating losses prior to October 2, 2013 except for net operating losses from its Puerto Rico entity which may be subject to Section 382 limitation.
The Company experienced a change in ownership on May 14, 2014. As a result, the Company’s NOL carryforwards and credits generated through the date of change are subject to an annual limitation under Section 382. Accordingly, if the Company generates sufficient taxable income, the NOL carryforwards or credits prior to the change in ownership are not expected to expire unutilized due to the Section 382 Limitation as of May 14, 2014.
The Company is required to recognize in the financial statements the impact of a tax position, if that position is more likely than not of being sustained on audit, based on the technical merits of the position. As of December 31, 2014, the Company does not have any unrecognized tax benefits and does not have any tax positions for which it is reasonably possible that the amount of gross unrecognized tax benefits will increase or decrease within 12 months after the year ended December 31, 2014.
The Company files income tax returns in the U.S. federal jurisdiction, various state jurisdictions and foreign jurisdictions for its Canadian, Chilean and Puerto Rican operations. The Company’s U.S. and foreign income tax returns for 2010 and forward are subject to examination.
The Company has a policy to classify accrued interest and penalties associated with uncertain tax positions together with the related liability, and the expenses incurred related to such accruals are included in the provision for income taxes. The Company did not incur any interest expense or penalties associated with unrecognized tax benefits for the years ended December 31, 2014, 2013 and 2012.
The Company has not established deferred income taxes with respect to $7.6 million of undistributed earnings of its Chilean subsidiary, since any U.S. income tax liability would be offset in whole by allowable tax credits deriving from income taxes paid to that foreign jurisdiction.
The Company operates under a tax holiday in Puerto Rico which enacted a special tax rate of 4% for business dedicated to the production of energy for consumption through the use of renewal sources. Act No. 73 of 2008, as amended, known as the “Economic Incentives for the Development of Puerto Rico Act” (the “Act”), promotes the development of green energy projects through economic incentives to reduce the island’s dependency on oil. The Act provides for a 4% flat income tax rate on green energy income (“GEI”) in lieu of any income tax imposed by the Puerto Rico Code for a 15 year period and is scheduled to terminate on December 31, 2026. The impact of the tax holiday decreased foreign deferred tax expense by $2.1 million for 2014. The impact of the tax holiday on net income per share of Class A common stock- basic and diluted and Class B common stock- basic and diluted were $0.0502 and $0.1368, respectively.

Stockholders_Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Stockholders' Equity	14	Stockholders’ Equity
	Common Stock
	Below is a summary of the rights and preferences of the Company’s Class A and Class B common stock as of December 31, 2014 and 2013. The Company’s Class B common stock converted on a one-to-one basis into Class A common stock on December 31, 2014.
	Voting Rights
	Holders of the Company’s Class A common stock and Class B common stock are entitled to one vote per share on all matters submitted to a vote of stockholders and will vote as a single class under all circumstances, unless otherwise required by law. Shares held by Pattern Development are entitled to certain approval rights if Pattern Development beneficially owns not less than thirty-three and one-third percent of the Company’s outstanding common stock, pursuant to the Shareholder Approval Rights Agreement between the Company and Pattern Development dated October 2, 2013.
	Dividend Rights
	Holders of Class A common stock are eligible to receive dividends on common stock held when funds are available and as approved by the Board of Directors. The Class B common stock converted after the determination of holders of record of Class A common stock, following the close of trading on December 31, 2014. On October 29, 2014, the Company declared its fourth quarter 2014 dividend, payable on January 30, 2015, to holders of record on December 31, 2014, in the amount of $0.335 per Class A common stock, which represents $1.34 on an annualized basis.
	Liquidation Rights
	In the event of any liquidation, dissolution or winding-up of the Company, holders of Class A common stock will be entitled to share ratably in the Company’s assets that remain after payment or provision for payment of all of its debts and obligations and after liquidation payments to holders of outstanding shares of preferred stock, if any.
	Preferred Stock
	The Company has 100,000,000 shares of authorized preferred stock issuable in one or more series. The Company’s Board of Directors is authorized to determine the designation, powers, preferences and relative, participating, optional or other special rights of any such series. As of December 31, 2014 and 2013, there was no preferred stock issued and outstanding.
	Conversion
	Upon the later of December 31, 2014 and the date on which its South Kent project achieves commercial operations (“Conversion Event”), all of the outstanding Class B common stock automatically convert, on a one-for-one basis, into Class A shares. There are no other conversion rights attached to Class B common stock. The Company’s South Kent project achieved commercial operations on March 28, 2014 and as a result, the Company’s Class B common stock converted into Class A common stock on December 31, 2014.
	Class B Common Stock—Beneficial Conversion Feature
	The contingency on the conversion of the Class B common stock was removed when the South Kent project achieved commercial operations on March 28, 2014. The removal of this contingency resulted in the recognition of a beneficial conversion feature in the Company’s additional paid-in capital account. The beneficial conversion feature represents the intrinsic value of the conversion feature, which is measured as the difference between the fair value of Class B common stock and the fair value of Class A common stock, into which the Class B common stock is convertible, as of October 2, 2013, which is the date of the Company’s initial public offering. The beneficial conversion feature is accreted on a straight-line basis from March 28, 2014 through December 31, 2014 into the Company’s additional paid-in capital account in the consolidated statements of stockholders’ equity, as there are no available retained earnings.
	Noncontrolling Interests
	The following table presents the noncontrolling interest balances, reported in stockholders’ equity in the consolidated balance sheets by project as of December 31, 2014 and 2013 (in thousands):
						Noncontrolling Ownership Percentage
		December 31,				December 31,
		2014		2013		2014			2013
	Gulf Wind	$	97,061	$	99,794		60	%		60	%
	El Arrayán		35,624		—		30	%		N/A
	Panhandle 1		205,333		—		21	%		N/A
	Panhandle 2		192,568		—		19	%		N/A
	Noncontrolling interest	$	530,586	$	99,794

Equity_Incentive_Award_Plan

Equity Incentive Award Plan	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Incentive Award Plan	15	Equity Incentive Award Plan
	In September 2013, the Company adopted the 2013 Equity Incentive Award Plan (“2013 Plan”), which permits the Company to issue 3,000,000 aggregate number of Class A common shares for equity awards including incentive and nonqualified stock options, restricted stock awards (“RSAs”) and restricted stock units to employees, directors and consultants. RSAs provide the holder with immediate voting rights, but are restricted in all other respects until released. Upon cessation of services to the Company, any unreleased RSAs will be cancelled. All unreleased RSAs accrue dividends and distributions, and are paid in cash upon release. During 2014, the Company granted 161,757 RSAs to certain employees and 16,332 RSAs to certain directors. As of December 31, 2014, 2,292,642 aggregate number of Class A shares were available for issuance under the 2013 Plan.
	Stock-Based Compensation
	The Company accounts for stock-based compensation related to stock options granted to employees by estimating the fair value of the stock-based awards using the Black-Scholes option-pricing model. The fair value of the stock options granted is amortized over the applicable vesting period. The Black-Scholes option pricing model includes assumptions regarding dividend yields, expected volatility, expected option term, expected forfeiture rate and risk-free interest rates. The Company estimates expected volatility based on the historical volatility of comparable publicly traded companies for a period that is equal to the expected term of the options. The risk-free interest rate is based on the U.S. treasury yield curve in effect at the time of grant for a period commensurate with the estimated expected life. The expected term of options granted is derived using the “simplified” method as allowed under the provisions of the ASC 718, Compensation—Stock Compensation, due to insufficient historical exercise history data to provide a reasonable basis upon which to estimate expected term due to the limited period of time its equity shares have been publicly traded. As such, expected term of options represents the period of time that options granted are expected to be outstanding.
	The stock-based compensation expense related to stock options and RSAs is recorded as a component of general and administrative expenses in the Company’s consolidated statements of operations and totaled $4.1 million and $0.5 million for the years ended December 31, 2014 and 2013, respectively.
	Stock Options
	For the years ended December 31, 2014 and 2013, the fair value of employee stock options was estimated using the Black-Scholes option pricing model. The following weighted average assumptions were used:
		Year ended December 31,
		2014			2013
	Stock options:
	Risk-free interest rate		1.68	%		1.68	%
	Expected life (in years)		5.8			5.8
	Expected volatility		36	%		36	%
	Expected dividend yield		5.7			5.7
	The following table summarizes stock option activity under the 2013 Plan for the year ended December 31, 2014:
								Weighted Average
								Remaining
		Number of Options			Weighted Average			Contractual Life		Aggregate
		Outstanding			Exercise Price			(in years)		Instrinsic Value
	Outstanding at December 31, 2013		444,823		$	22
	Exercised		(14,861	)		22				$	108,191
	Outstanding at December 31, 2014		429,962		$	22			8.8	$	1,143,699
	Exercisable at December 31, 2014		170,434		$	22			8.8	$	453,354
	Vested and expected to vest as of December 31, 2014		429,962		$	22			8.8	$	1,143,699
	The aggregate intrinsic value of options exercised was $0.1 million and $0 for the years ended December 31, 2014 and 2013. Intrinsic value is defined as the amount by which the fair value of the underlying stock exceeds the exercise price at the time of option exercise. The total cash received from employees as a result of employee stock option exercises during fiscal year 2014 was $0.3 million. No employee stock options were exercised during the year ended December 31, 2013.
	As of December 31, 2014 the total unrecorded stock-based compensation expense for unvested stock options shares was $1.1 million, which is expected to be amortized over a weighted-average period of 1.8 years.
	Restricted Stock Awards
	The Company measures the fair value of RSAs at the grant date and accounts for stock-based compensation by amortizing the fair value on a straight line basis over the related vesting period.
	The following table summarizes restricted stock awards activity under the 2013 Plan for the year ended December 31, 2014:
					Weighted Average			Aggregate
		Number of RSAs			Grant Date			Intrinsic
		Outstanding			Fair Value			Value
	Balance at December 31, 2013		76,262			22.53
	Granted		178,089			27.54
	Released		(81,914	)		26.64
	Forfeited		(2,174	)		27.03
	Repurchased for employee tax withholding		(24,531	)		26.44
	Balance at December 31, 2014		145,732		$	25.62		$	3,593,751
	For the years ended December 31, 2014 and 2013, the total fair value of restricted stock awards released was $2.9 million and $0.2 million, based on the weighted average grant date fair values of $26.64 and $24.15 for the years ended December 31, 2014 and 2013, respectively.
	As of December 31, 2014, the total unrecorded stock-based compensation expense for unreleased restricted stock awards was $3.1 million, which is expected to be amortized over a weighted-average period of 1.8 years.
	Restricted Stock Awards that contain Performance Conditions
	During the year ended December 31, 2014, the Company recorded compensation expense of $0.6 million related to restricted stock awards, granted in March 2014, that will be released to senior management personnel once performance conditions have been met. These awards include 27,717 shares of restricted stock, with a weighted average grant date fair value of $27.03 that will be released if the Company reaches its cash available for distribution target as of December 31, 2014. On December 31, 2014, the performance condition was met.
	As of December 31, 2014, there were no unvested restricted stock awards that contain performance conditions.

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Share	16	Earnings Per Share
	The Company computes earnings (loss) per share (“EPS”) for Class A and Class B common stock using the two-class method. The Company computes diluted EPS for Class A and Class B common stock using either the two-class method or the if-converted method, whichever is more dilutive. Class B common stock was converted to Class A common stock on a one-to-one basis on December 31, 2014. The computation of diluted EPS of Class A common stock included the impact of the conversion of the Class B common stock, if dilutive for Class A common stock, using the two class method or the if-converted method, whichever was more dilutive. The rights, including voting and liquidation rights, of the holders of the Class A and Class B common stock were identical, except with respect to dividends, as the Class B common stock were not entitled to dividends.
	Basic EPS is computed for each class of common stock by allocating net income attributable to controlling interest to Class A common stock for dividends declared or accumulated during the current period that must be paid for the current period, and to Class B common stock for deemed dividends representing accretion from the beneficial conversion feature. Net loss attributable to common stockholders is allocated to Class A and Class B common stock proportionally, as if all of the losses for the period have been distributed. Net income attributable to common stockholders is allocated only to Class A common stock because Class B common stock is not entitled to receive distributions.
	Diluted EPS is computed by dividing net income attributable to controlling interest by the weighted-average number of common shares and potentially dilutive common shares outstanding, for each respective class of common stock. Potentially dilutive common stock includes the dilutive effect of the common stock underlying in-the-money stock options and is calculated based on the average share price for each period using the treasury stock method. Potentially dilutive common stock also reflects the dilutive effect of unvested restricted stock awards.
	The computations for basic and diluted earnings (loss) per share are as follows:
		Year ended December 31,
		2014			2013
	Numerator for basic and diluted earnings (loss) per share:
	Net loss attributable to controlling interest	$	(31,290	)	$	(13,336	)
	Less: dividends declared		(56,976	)		(11,103	)
	Less: deemed dividends		(21,901	)		—
	Undistributed loss	$	(110,167	)	$	(24,439	)
	Denominator for basic and diluted loss per share:
	Weighted average number of shares:
	Class A common stock—basic		42,361,959			35,448,056
	Add dilutive effect of:
	Stock options		52,915			14,462
	Restricted stock awards		27,401			38,131
	Class B common stock		15,555,000			15,555,000
	Class A common stock—fully diluted		57,997,275			51,055,649
	Less: antidilutive securities
	Stock options		(52,915	)		(14,462	)
	Restricted stock awards		(27,401	)		(38,131	)
	Class B common stock		(15,555,000	)		(15,555,000	)
	Class A common stock—diluted (excluding antidilutive securities)		42,361,959			35,448,056
	Class B common stock—basic and diluted		15,555,000			15,555,000
	Calculation of basic and diluted earnings (loss) per share:
	Class A common stock:
	Dividends	$	1.34		$	0.31
	Undistributed loss		(1.90	)		(0.48	)
	Basic loss per share	$	(0.56	)	$	(0.17	)
	Class A common stock:
	Diluted loss per share	$	(0.56	)	$	(0.17	)
	Class B common stock:
	Deemed dividends	$	1.41		$	—
	Undistributed loss		(1.90	)		(0.48	)
	Basic and diluted loss per share	$	(0.49	)	$	(0.48	)
	Cash dividends declared per Class A common share	$	1.3		$	0.31
	Deemed dividends per Class B common share	$	1.41		$	—

Geographic_Information

Geographic Information	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Geographic Information	17	Geographic Information
	The table below provides information, by country, about the Company’s consolidated operations. Revenue is recorded in the country in which it is earned and assets are recorded in the country in which they are located (in thousands):
		Revenue						Property, Plant and Equipment, net
		Year ended December 31,						December 31,
		2014		2013		2012		2014		2013
	United States	$	201,408	$	161,505	$	73,089	$	1,784,219	$	1,210,319
	Canada		46,593		40,068		41,439		233,690		265,823
	Chile		17,492		—		—		332,947		—
	Total	$	265,493	$	201,573	$	114,528	$	2,350,856	$	1,476,142

Commitments_Contingencies_and_

Commitments, Contingencies and Warranties	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Warranties	18	Commitments, Contingencies and Warranties
	From time to time, the Company has become involved in claims and legal matters arising in the ordinary course of business. Management is not currently aware of any matters that will have a material adverse effect on the financial position, results of operations, or cash flows of the Company.
	Power Purchase Agreements
	The Company has various PPAs that terminate from 2025 to 2039. The terms of the PPAs generally provide for the annual delivery of a minimum amount of electricity at fixed prices and in some cases include price escalation over the term of the respective PPAs. As of December 31, 2014, under the terms of the PPAs, the Company issued irrevocable letters of credit totaling $57.2 million to ensure its performance for the duration of the PPAs.
	Project Finance Agreements
	The Company has various project finance agreements which obligate the Company to provide certain reserves to enhance its credit worthiness and facilitate the availability of credit. As of December 31, 2014, the Company issued irrevocable letters of credit totaling $107.1 million, of which $45.1 million was from the Company’s revolving credit facility, to ensure performance under these various project finance agreements.
	Land Leases
	The Company has entered into various long-term land leases. Rent expense, included in project expense in the consolidated statements of operations, was $8.8 million, $6.1 million and $4.2 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	The future minimum payments related to these leases as of December 31, 2014, are as follows (in thousands):
	For the year ending December 31,
	2015	$	5,971
	2016		5,406
	2017		5,412
	2018		5,418
	2019		5,425
	Thereafter		141,443
	Total	$	169,075
	Service and Maintenance Agreements
	The Company has entered into service and maintenance agreements with third party contractors to provide operations and maintenance services, modifications and upgrades for varying periods over the next twelve years. As of December 31, 2014, outstanding commitments with these vendors were $353.4 million, payable over the full term of these agreements.
	The following table presents operations and maintenance commitments over the next five years (in thousands):
	For the year ending December 31,
	2015	$	40,118
	2016		44,583
	2017		44,387
	2018		38,746
	2019		36,707
	Thereafter		148,872
	Total	$	353,413
	Purchase, Construction and Other Commitments
	The Company has entered into various commitments with service providers related to the Company’s projects and operations of its business. Outstanding commitments with these vendors, excluding operations and maintenance commitments were $16.7 million, as of December 31, 2014. The Company also has construction-related open commitments of $171.0 million as of December 31, 2014. In addition, the Company has a commitment to purchase $6.3 million of wind turbine spare parts from a third party contractor under a maintenance and service agreement.
	The Company has total commitments of $6.7 million over approximately the next 20 years to local community and government organizations surrounding certain wind farms.
	Turbine Availability Warranties
	The Company has various turbine availability warranties from its turbine manufacturers. Pursuant to these warranties, if a turbine operates at less than minimum availability during the warranty period, the turbine manufacturer is obligated to pay, as liquidated damages, a fee for each percent that the turbine operates below the minimum availability threshold. In addition, pursuant to certain of these warranties, if a turbine operates at more than a specified availability during the warranty period, the Company has an obligation to pay a bonus to the turbine manufacturer. As of December 31, 2014 and 2013, the Company did not record a contingent liability associated with bonuses to the turbine manufacturers.
	In 2013, the Company entered into warranty settlements with a turbine manufacturer for blade related wind turbine outages. The warranty settlements provide for total liquidated damage payments of approximately $21.9 million for the year ended December 31, 2013. During the year ended December 31, 2013, the Company received payments of $24.1 million, in connection with these warranty settlements. As of December 31, 2014 and 2013, the Company recorded $0.6 million and $2.2 million, respectively, in accrued liability, representing the maximum future refund of liquidated damage payments to the turbine manufacturer. The warranty settlements received, net of the maximum potential future refund to the wind turbine manufacturer were recorded as other revenue in the consolidated statements of operations.
	Long-Term Service Guarantees
	The Company has service guarantees from its turbine service and maintenance providers. These service guarantees are associated with long-term turbine service arrangements which commenced on various dates in 2014 and will commence on various dates in 2015 for certain wind projects. Pursuant to these guarantees, if a turbine operates at less than minimum availability during the guarantee period, the service provider is obligated to pay, as liquidated damages, a fee for each percent that the turbine operates below the minimum availability threshold. In addition, pursuant to certain of these guarantees, if a turbine operates at more than a specified availability during the guarantee period, the Company has an obligation to pay a bonus to the service provider. As of December 31, 2014, the Company recorded liabilities of $0.2 million associated with bonuses to service providers.
	Contingent Liabilities
	In 2014, the Company recorded a contingent obligation, payable to a third party, related to the acquisition of Logan’s Gap. Pursuant to the agreement, the Company is obligated to pay an additional $4.0 million upon the earlier of commercial operations or tax equity funding, which is expected to occur in the fourth quarter of 2015.
	Indemnity
	The Company provides a variety of indemnities in the ordinary course of business to contractual counterparties and to our lenders and other financial partners. Hatchet Ridge agreed to indemnify the lender that provided financing for Hatchet Ridge against certain tax losses in connection with its sale-leaseback financing transaction in December 2010. The indemnity agreement is effective for the duration of the sale-leaseback financing.
	The Company is party to certain indemnities for the benefit of the Spring Valley, Santa Isabel and Ocotillo project finance lenders. These indemnity obligations consist principally of indemnities that protect the project finance lenders from the potential effect of any recapture by the U.S. Department of the Treasury, or “U.S. Treasury,” of any amount of the ITC cash grants previously received by the projects. The ITC cash grant indemnity obligations guarantee amounts of any cash grant made to each of the respective projects that may subsequently be recaptured. In addition, the Company is also party to an indemnity of our Ocotillo project finance lenders in connection with certain legal matters, which is limited to the amount of certain related costs and expenses.
	Santa Isabel agreed to indemnify unrelated third parties against certain tax losses in connection with monetization of tax credits under the Economic Incentives for the Development of Puerto Rico Act of May 28, 2008 for $7.2 million.

Related_Party_Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transactions	19	Related Party Transactions
	From inception to October 1, 2013, the Company’s project management and administrative activities were provided by Pattern Development. Costs associated with these activities were allocated to the Company and recorded in its consolidated statements of operations. Allocated costs include cash and non-cash compensation, other direct, general and administrative costs, and non-operating costs deemed allocable to the Company. Measurement of allocated costs is based principally on time devoted to the Company by officers and employees of Pattern Development. The Company believes the allocated costs presented in its consolidated statements of operations are a reasonable estimate of actual costs incurred to operate the business. The allocated costs are not the result of arms-length, free-market dealings.
	Management Services Agreement and Shared Management
	Effective October 2, 2013, the Company entered into a bilateral Management Services Agreement with Pattern Development which provides for the Company and Pattern Development to benefit, primarily on a cost-reimbursement basis, plus a 5% fee on certain direct costs, from the parties’ respective management and other professional, technical and administrative personnel, all of whom will report to and be managed by the Company’s executive officers. Pursuant to the Management Services Agreement, certain of the Company’s executive officers, including its Chief Executive Officer, will also serve as executive officers of Pattern Development and devote their time to both the Company and Pattern Development as is prudent in carrying out their executive responsibilities and fiduciary duties. The Company refers to the employees who will serve as executive officers of both the Company and Pattern Development as the “shared PEG executives.” The shared PEG executives will have responsibilities for both the Company and Pattern Development and, as a result, these individuals will not devote all of their time to the Company’s business. Under the terms of the Management Services Agreement, Pattern Development is required to reimburse the Company for an allocation of the compensation paid to such shared PEG executives reflecting the percentage of time spent providing services to Pattern Development.
	The table below presents allocated costs prior to October 2, 2013 and net bilateral management service cost reimbursements on and after October 2, 2013 included in the consolidated statements of operations (in thousands):
		December 31,
		2014			2013			2012
	Project expense	$	—		$	1,995		$	1,998
	Related party general and administrative		5,787			8,169			10,604
	Related party income		(2,612	)		(665	)		—
	Other income, net		—			(551	)		(210	)
	Total	$	3,175		$	8,948		$	12,392
	Prior to the Contribution Transactions, the Company had purchase arrangements with Pattern Development under which the latter purchased various services and supplies on behalf of the Company and received reimbursement for these purchases. As of December 31, 2014 and 2013, the net amounts payable to Pattern Development for these purchases were $0.8 million and $1.2 million, respectively. In addition, the Company recorded a receivable of $0.1 million and $0 for the years ended December 31, 2014 and 2013, respectively, for IPO cost reimbursements due from Pattern Development.
	Letters of credit, indemnities and guarantees
	Pattern Development provided letters of credit that secure the Company’s obligations under PPAs and interconnection agreements. There were no letters of credit outstanding as of December 31, 2014 and 2013, respectively.
	Pattern Development agreed to guarantee $14.0 million of El Arrayán’s payment obligations to a lender that has provided a $20 million credit facility for financing of El Arrayán’s recoverable, construction-period value added tax payments. The remaining $6.0 million of the credit facility has been guaranteed by another investor in El Arrayán.
	Purchase and Sales Agreements
	On December 20, 2013, the Company acquired a 45.0% equity interest in Grand from Pattern Development. Subject to the terms of this agreement, the Company may make an additional contingent payment of up to C$5.0 million, or $4.3 million based on the exchange rate as of December 31, 2014, as calculated based on final budget to actual amounts and distributions payable to Pattern Development upon term conversion.
	On June 25, 2014, the Company acquired a 100% equity interest in AEI El Arrayán, an entity holding a 38.5% indirect interest in El Arrayán, for a total purchase price of approximately $45.3 million. The Company owned a 31.5% indirect interest in El Arrayán prior to acquiring the additional 38.5% interest in order to obtain majority control, or 70% interest, in the project. El Arrayán is a 115 MW wind power project, located in Ovalle, Chile.
	On June 30, 2014, the Company acquired 100% of the Class B membership interests in the Panhandle 1 wind project, representing a 79% initial ownership interest in the project’s distributable cash flow, through the acquisition of Panhandle Wind Holdings LLC, from Pattern Development, for a purchase price of approximately $124.4 million. This represents a 172 MW interest in the 218 MW wind project, located in Carson County, Texas.
	On September 5, 2014, the Company exercised its right to acquire the name “Pattern” and the Pattern logo from Pattern Development pursuant to a Service Mark Purchase and Sale Agreement for a purchase price of $1. The Company granted to Pattern Development a license to use the name “Pattern” and the Pattern logo.
	On November 10, 2014, the Company completed its acquisition of 100% of the Class B membership interests in the Panhandle 2 wind project, representing a 81% initial ownership interest in the project’s distributable cash flow, through the acquisition of Panhandle B Member 2, from Pattern Development, for a purchase price of approximately $123.8 million, which includes debt assumed of $195.4 million that was repaid immediately after acquisition. This represents a 147 MW interest in the 182 MW wind project, located in Carson County, Texas.
	On December 19, 2014, the Company acquired 100% of the membership interests in Logan’s Gap from Pattern Development, for a purchase price of approximately $15.1 million. In connection with the acquisition, as of December 31, 2014, the Company has a related party payable of $5.0 million to Pattern Development. In addition, the Company has a contingent payment of up to $4.0 million to an unrelated third party at the earlier of (a) commercial operations or (b) tax equity funding. Logan’s Gap is a 164 MW wind project located in Comanche County, Texas.
	Puerto Rico Electric Power Authority (PREPA)
	The Company’s Santa Isabel project was in a dispute with PREPA over the appropriate rate being charged to the project for the electric services it uses. During the year ended December 31, 2013, the difference between what the Company believes is the appropriate monthly charge and PREPA’s bill was resolved in principle, and billing is now per the understanding between the parties. Pattern Development provided the Company with an indemnity to mitigate the economic impact on the Company of this dispute.
	Management fees
	The Company provides operations and management services and receives a fee for such services under agreements with its joint venture investees, South Kent, Grand and, prior to its acquisition on June 25, 2014, El Arrayán. Management fees of $3.3 million and $0.9 million were recorded as related party revenue in the consolidated statements of operations for the years ended December 31, 2014 and 2013, respectively and a related party receivable of $0.7 million and $0.2 million were recorded in the consolidated balance sheet as of December 31, 2014 and 2013, respectively. The Company eliminates the intercompany profit from management fees related to its ownership interest in South Kent and Grand. Management fees related to El Arrayán, earned subsequent to June 25, 2014, are eliminated upon consolidation.
	Employee Savings Plan
	The Company participates in a 401(k) plan sponsored and maintained by Pattern Development, established on August 3, 2009 and restated on October 3, 2013. The Company also sponsors a Canadian Registered Retirement Savings Plan (“RRSP”), established on October 2, 2013. Participants in the plans are allowed to defer a portion of their compensation, not to exceed the respective Internal Revenue Service (IRS) or Canada Revenue Agency (CRA) annual allowance contribution guidelines, and are 100% vested in their respective deferrals and earnings. Participants may choose from a variety of investment options. The Company contributes 5% of base compensation to each employee’s 401(k) or RRSP account, up to the annual compensation limit. For the years ended December 31, 2014 and 2013, the Company contributed $0.3 million and $0.1 million, respectively, which was recorded in the consolidated statements of operations as either general and administrative expense or cost of revenue. No such contributions were made during the year ended December 31, 2012.

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data	20	Selected Quarterly Financial Data (Unaudited)
	The following tables summarize the Company’s unaudited quarterly consolidated statements of operations for each of the eight quarters in the two year period ended December 31, 2014. The quarterly consolidated statements of operations data were prepared on a basis consistent with the audited consolidated financial statements included in Part III, Item 14, “Financial Statements and Supplementary Data” in this Annual Report on Form 10-K.
	Quarterly financial data in thousands, except per share data:
		Three months ended
		December 31,			September 30,			June 30,			March 31,
		2014			2014			2014			2014
	Revenue	$	79,418		$	71,519		$	65,007		$	49,549
	Gross profit	$	26,311		$	17,669		$	27,023		$	12,298
	Net (loss) income	$	(15,986	)	$	(9,281	)	$	7,167		$	(21,899	)
	Net (loss) income attributable to noncontrolling interest	$	4,406		$	(2,073	)	$	(4,032	)	$	(7,010	)
	Net (loss) income attributable to controlling interest	$	(20,392	)	$	(7,208	)	$	11,199		$	(14,889	)
	Basic (loss) earnings per share—Class A	$	(0.36	)	$	(0.15	)	$	0.17		$	(0.20	)
	Diluted (loss) earnings per share—Class A	$	(0.36	)	$	(0.15	)	$	0.16		$	(0.29	)
	Basic and diluted earnings (loss) per share—Class B	$	(0.23	)	$	(0.02	)	$	0.28		$	(0.51	)
	Cash dividends declared per Class A common share	$	0.34		$	0.33		$	0.32		$	0.31
	Deemed dividends on Class B common shares	$	0.46		$	0.46		$	0.48		$	—
		Three months ended
		December 31,			September 30,			June 30,			March 31,
		2013			2013			2013			2013
	Revenue	$	41,767		$	57,257		$	58,712		$	43,837
	Gross profit	$	4,729		$	21,471		$	26,222		$	8,294
	Net (loss) income	$	(19,376	)	$	4,244		$	43,988		$	(18,784	)
	Net (loss) income attributable to noncontrolling interest	$	(6,197	)	$	3,248		$	(359	)	$	(3,579	)
	Net (loss) income attributable to controlling interest	$	(13,179	)	$	996		$	44,347		$	(15,205	)
	Basic and diluted loss per share—Class A	$	(0.17	)		N/A			N/A			N/A
	Basic and diluted loss per share—Class B	$	(0.48	)		N/A			N/A			N/A
	In connection with the preparation of the consolidated financial statements for the periods ended September 30, 2014, June 30, 2014 and March 31, 2014, errors in the reporting and computation and disclosure of earnings (loss) per share were identified.
	For the three and nine month periods ended September 30, 2014, the Company determined it made an error in reporting the weighted average number of shares outstanding of Class A common stock which affected the earnings (loss) per share calculations reported.
	The Company evaluated the materiality of this error in accordance with SEC Staff Accounting Bulletin No. 99, Materiality, and SEC Staff Accounting Bulletin No. 108, Considering the Effects of Prior Year Misstatements When Quantifying Misstatements in Current Year Financial Statements, and concluded that this error, individually and in the aggregate, was immaterial to the three and nine months ended September 30, 2014. While the adjustment was immaterial, the Company has elected to revise the previously reported weighted average shares outstanding and basic and diluted earnings per share, for the three and nine months ended September 30, 2014.
	For the three and six month periods ended June 30, 2014, the Company determined that the computation of earnings (loss) per share did not correctly consider the recognition of a beneficial conversion feature of the Class B common stock and the subsequent accretion of this beneficial conversion feature, as a result of the commencement of commercial operations at the Company’s South Kent project, on March 28, 2014. The recognition of this beneficial conversion feature and subsequent accretion had no net impact to the consolidated balance sheets, consolidated statement of stockholders’ equity or consolidated statements of cash flows, and no impact on net income in the consolidated statements of operations. However, the subsequent accretion of the beneficial conversion feature is considered a deemed dividend to the Class B common stockholders for the purposes of calculating net loss attributable to common stockholders and earnings (loss) per share. The deemed dividend does not represent a current or future distribution of the Company’s earnings.
	For the three month period ended March 31, 2014, the Company determined that the computation and disclosure of Class A diluted earnings per share did not correctly consider that upon the commercial operation date of South Kent on March 28, 2014, the “if-converted” method of calculating diluted earnings (loss) per share would result in a more dilutive result than the previously applied “two-class” method of calculating diluted earnings (loss) per share. The more dilutive result of these two methods should have been reported on the Company’s consolidated statements of operations.
	For each of the periods ended June 30, 2014 and March 31, 2014, the Company evaluated the materiality of the errors identified in accordance with SEC Staff Accounting Bulletin No. 99, Materiality, and SEC Staff Accounting Bulletin No. 108, Considering the Effects of Prior Year Misstatements When Quantifying Misstatements in Current Year Financial Statements, and concluded that the errors, individually and in the aggregate, were material and as a result, the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2014 and the Company’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2014, were restated to correct errors in the computation and disclosure of earnings (loss) per share.
	The following table presents the basic and diluted earnings (loss) per share as previously reported and as revised for the three and nine months ended September 30, 2014:
		Three months ended						Nine months ended
		September 30, 2014						September 30, 2014
		As Reported			As Revised			As Reported			As Revised
	Numerator for basic and diluted earnings (loss) per share:
	Net loss attributable to controlling interest	$	(7,208	)	$	(7,208	)	$	(10,898	)	$	(10,898	)
	Less: cash dividends declared on Class A common shares		(15,258	)		(15,258	)		(41,395	)		(41,395	)
	Less: deemed dividends on Class B common shares		(7,222	)		(7,222	)		(14,679	)		(14,679	)
	Net loss attributable to common stockholders	$	(29,688	)	$	(29,688	)	$	(66,972	)	$	(66,972	)
	Denominator for basic and diluted loss per share:
	Weighted average number of shares:
	Class A common stock—basic		40,980,989			46,317,932			38,342,998			41,022,962
	Add dilutive effect of:
	Stock options		133,197			133,197			112,252			112,252
	Restricted stock awards		191,451			191,451			191,451			191,451
	Class B common stock		15,555,000			15,555,000			15,555,000			15,555,000
	Class A common stock—fully diluted		56,860,637			62,197,580			54,201,701			56,881,665
	Less: antidilutive securities
	Stock options		(133,197	)		(133,197	)		(112,252	)		(112,252	)
	Restricted stock awards		(191,451	)		(191,451	)		(191,451	)		(191,451	)
	Class B common stock		(15,555,000	)		(15,555,000	)		—			—
	Class A common stock—diluted (excluding antidilutive securities)		40,980,989			46,317,932			53,897,998			56,577,962
	Class B common stock—basic and diluted		15,555,000			15,555,000			15,555,000			15,555,000
	Calculation of basic and diluted earnings (loss) per share:
	Class A common stock:
	Dividends	$	0.37		$	0.33		$	1.08		$	1.01
	Undistributed loss		(0.53	)		(0.48	)		(1.24	)		(1.18	)
	Basic loss per share	$	(0.15	)	$	(0.15	)	$	(0.16	)	$	(0.17	)
	Class A common stock:
	Diluted loss per share	$	(0.15	)	$	(0.15	)	$	(0.20	)	$	(0.19	)
	Class B common stock:
	Deemed dividends	$	0.46		$	0.46		$	0.94		$	0.94
Undistributed loss		(0.53	)		(0.48	)		(1.24	)		(1.18	)
Basic and diluted loss per share	$	(0.06	)	$	(0.02	)	$	(0.30	)	$	(0.24	)
Cash dividends declared per Class A common share	$	0.33		$	0.33		$	0.96		$	0.96
Deemed dividends per Class B common share	$	0.46		$	0.46		$	0.94		$	0.94
The following table presents the basic and diluted earnings (loss) per share as previously reported and as revised for the three and six months ended June 30, 2014:
	Three months ended						Six months ended
	June 30, 2014						June 30, 2014
	As Reported			As Restated			As Reported			As Restated
Numerator for basic and diluted earnings (loss) per share:
Net income (loss) attributable to controlling interest	$	11,199		$	11,199		$	(3,690	)	$	(3,690	)
Less: cash dividends declared on Class A common shares		(14,981	)		(14,981	)		(26,138	)		(26,138	)
Less: deemed dividends on Class B common shares		—			(7,457	)		—			(7,457	)
Net loss attributable to common stockholders	$	(3,782	)	$	(11,239	)	$	(29,828	)	$	(37,285	)
Denominator for earnings (loss) per share:
Weighted average number of shares:
Class A common stock—basic		41,174,697			41,174,697			38,331,595			38,331,595
Add dilutive effect of:
Stock options		107,979			107,979			100,814			100,814
Restricted stock awards		227,543			227,543			227,543			227,543
Class B common stock		15,555,000			15,555,000			15,555,000			15,555,000
Class A common stock—fully diluted		57,065,219			57,065,219			54,214,952			54,214,952
Less: antidilutive securities
Stock options		—			—			—			(100,814	)
Restricted stock awards		—			—			—			(227,543	)
Class B common stock		—			(15,555,000	)		—			—
Class A common stock—diluted (excluding antidilutive securities)		57,065,219			41,510,219			54,214,953			53,886,595
Class B common stock—basic and diluted		15,555,000			15,555,000			15,555,000			15,555,000
Calculation of basic and diluted earnings (loss) per share:
Class A common stock:
Dividends	$	0.36		$	0.36		$	0.68		$	0.68
Undistributed loss		(0.07	)		(0.20	)		(0.55	)		(0.69	)
Basic earnings (loss) per share	$	0.3		$	0.17		$	0.13		$	(0.01	)
Class A common stock:
Diluted earnings (loss) per share	$	0.2		$	0.16		$	(0.07	)	$	(0.07	)
Class B common stock:
Deemed dividends	$	—		$	0.48		$	—		$	0.48
Undistributed loss		(0.07	)		(0.20	)		(0.55	)		(0.69	)
Basic and diluted earnings (loss) per share	$	(0.07	)	$	0.28		$	(0.55	)	$	(0.21	)
Cash dividends declared per Class A common share	$	—		$	0.32		$	—		$	0.63
Deemed dividends per Class B common share	$	—		$	0.48		$	—		$	0.48
The following table presents the basic and diluted earnings (loss) per share as previously reported and as revised for the three months ended March 31, 2014:
	Three months ended
	March 31, 2014
	As Reported			As Restated
Numerator for basic and diluted earnings per share:
Net income (loss) attributable to controlling interest	$	(14,889	)	$	(14,889	)
Less: cash dividends declared on Class A common shares		(11,179	)		(11,179	)
Net loss attributable to common stockholders	$	(26,068	)	$	(26,068	)
Denominator for loss per share:
Weighted average number of shares:
Class A common stock—basic		35,533,166			35,533,166
Add dilutive effect of:
Stock options		95,219			95,219
Restricted stock awards		238,546			238,546
Class B common stock		15,555,000			15,555,000
Class A common stock—fully diluted		51,421,931			51,421,931
Less: antidilutive securities
Stock options		(95,219	)		—
Restricted stock awards		(238,546	)		—
Class B common stock		(15,555,000	)		—
Class A common stock—diluted (excluding antidilutive securities)		35,533,166			51,421,931
Class B common stock—basic and diluted		15,555,000			15,555,000
Calculation of basic and diluted loss per share:
Class A common stock:
Dividends	$	0.31		$	0.31
Undistributed loss		(0.51	)		(0.51	)
Basic loss per share	$	(0.20	)	$	(0.20	)
Class A common stock:
Diluted loss per share	$	(0.20	)	$	(0.29	)
Class B common stock:
Basic and diluted loss per share	$	(0.51	)	$	(0.51	)

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	21	Subsequent Events
	On February 24, 2015, the Company approved an increased dividend for the first quarter 2015, payable on April 30, 2015, to holders of record on March 31, 2015, in the amount of $0.342 per Class A share, which represents $1.368 on an annualized basis. This represents a 2% increase from the fourth quarter 2014 dividend of $0.335.
	On February 9, 2015, the Company completed an underwritten public offering of its Class A common stock. In total, 12,000,000 shares of the Company’s Class A common stock were sold. Of this amount, the Company issued and sold 7,000,000 shares of its Class A common stock and Pattern Development, the selling stockholder, sold 5,000,000 shares of its Class A common stock. The Company received net proceeds of approximately $196.6 million after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company. The Company did not receive any proceeds from the sale of shares sold by Pattern Development. As a result of the sale of shares by Pattern Development, its ownership interest in the Company decreased from 35% to 25% and it is no longer entitled to certain approval rights pursuant to the Shareholder Approval Rights Agreement dated October 2, 2013.

Schedule_ICondensed_ParentComp

Schedule I-Condensed Parent-Company Financial Statements	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule I-Condensed Parent-Company Financial Statements	Schedule I—Condensed Parent-Company Financial Statements
	Pattern Energy Group Inc.
	Condensed Financial Information of Parent
	Balance Sheets
	(In thousands of U.S. dollars, except share data)
			December 31,			December 31,
			2014			2013
	Assets
	Current assets:
	Cash and cash equivalents		$	34,772		$	75,776
	Related party receivable			1,982			1,000
	Current deferred tax assets			307			—
	Prepaid expenses and other current assets			4,484			446
	Total current assets			41,545			77,222
	Investments in subsidiaries			586,641			300,216
	Investments in affiliates			29,079			107,055
	Net deferred tax assets			147			573
	Other assets			85			—
	Total assets		$	657,497		$	485,066
	Liabilities and equity
	Current liabilities:
	Accounts payable and other accrued liabilities		$	6,404		$	4,513
	Related party payable			757			667
	Dividend payable			15,734			11,103
	Current deferred tax liabilities			147			—
	Total current liabilities			23,042			16,283
	Net deferred tax liabilities			307			573
	Total liabilities			23,349			16,856
	Equity:
	Class A common stock, $0.01 par value per share: 500,000,000 shares authorized; 62,088,306 and 35,531,720 shares issued as of December 31, 2014 and 2013, respectively; 62,062,841 and 35,530,786 shares outstanding as of December 31, 2014 and 2013, respectively			621			355
	Class B convertible common stock, $0.01 par value per share: 20,000,000 shares authorized; 0 and 15,555,000 shares issued as of December 31, 2014 and 2013, respectively; 0 and 15,555,000 outstanding as of December 31, 2014 and 2013, respectively			—			156
	Additional paid-in capital			696,378			461,852
	Capital			—			—
	Accumulated (loss) income			(17,066	)		14,224
	Accumulated other comprehensive loss			(45,068	)		(8,353	)
	Treasury stock, at cost; 25,465 and 934 shares of Class A common stock as of December 31, 2014 and 2013, respectively			(717	)		(24	)
	Total equity			634,148			468,210
	Total liabilities and equity		$	657,497		$	485,066
	See accompanying notes to parent company financial statements
	Pattern Energy Group Inc.
	Condensed Financial Information of Parent
	Statements of Operations and Comprehensive Income (Loss)
	(In thousands of U.S. dollars)
			Year ended December 31,						October 17, 2012
									(initial capitalization)
			2014			2013			to December 31, 2012
	Revenue		$	—		$	—		$	—
	Expenses			23,089			3,630			7
	Operating loss			(23,089	)		(3,630	)		(7	)
	Other income (expense):
	Equity in earnings (loss) from subsidiaries			18,064			12,641			(2,688	)
	Equity in (loss) earnings from affiliates			(25,295	)		7,846			(40	)
	Related party income			2,612			665			—
	Other expenses, net			(3,566	)		(563	)		—
	Other (expense) income			(8,185	)		20,589			(2,728	)
	Net (loss) income before income tax			(31,274	)		16,959			(2,735	)
	Tax provision			16			—			—
	Net (loss) income			(31,290	)		16,959			(2,735	)
	Other comprehensive income (loss), net of tax
	Proportionate share of subsidiaries’ other comprehensive (loss) income activity, net of tax benefit of $734, $0 and $0, respectively			(30,724	)		23,478			1,876
	Proportionate share of equity investee’s other comprehensive (loss) income activity, net of tax benefit (provision) of $1,855, ($615) and $302, respectively			(5,991	)		2,473			—
	Total other comprehensive (loss) income, net of tax			(36,715	)		25,951			1,876
	Comprehensive (loss) income		$	(68,005	)	$	42,910		$	(859	)
	See accompanying notes to parent company financial statements
Pattern Energy Group Inc.
Condensed Financial Information of Parent
Condensed Statements of Cash Flows
(In thousands of U.S. dollars)
		Year ended December 31,						October 17, 2012
								(initial capitalization)
		2014			2013			to December 31, 2012
Operating activities
Net (loss) income		$	(31,290	)	$	16,959		$	(2,735	)
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Stock-based compensation			4,105			511			—
Net loss on transactions			1,473			—			—
Equity in (earnings) loss from subsidiaries			(18,064	)		(12,641	)		2,688
Equity in loss (earnings) from affiliates			25,295			(7,846	)		40
Changes in operating assets and liabilities:
Prepaid expenses and other current assets			(3,545	)		(446	)		—
Accounts payable and other accrued liabilities			1,999			93			7
Related party receivable/payable			(639	)		(1,007	)		—
Net cash used in operating activities			(20,666	)		(4,377	)		—
Investing activities
Distribution from subsidiaries			108,581			233,226			—
Contribution to subsidiaries			(362,533	)		(172,130	)		—
Net cash (used in) provided by investing activities			(253,952	)		61,096			—
Financing activities
Proceeds from public offering, net of expenses			286,757			317,926			—
Proceeds from exercise of stock options			327			—			—
Repurchase of shares for employee tax withholding			(693	)		(24	)		—
Capital contributions—Pattern Development			—			32,678			1
Capital distributions—Pattern Development			—			(98,884	)		—
Capital distributions—Contribution Transactions			—			(232,640	)		—
Dividends paid			(52,344	)		—			—
Payment for deferred equity issuance costs			(433	)		—			—
Net cash provided by financing activities			233,614			19,056			1
Net change in cash and cash equivalents			(41,004	)		75,775			1
Cash and cash equivalents at beginning of period			75,776			1			—
Cash and cash equivalents at end of period		$	34,772		$	75,776		$	1
Schedule of non-cash activities
Investments in subsidiaries		$	—		$	—		$	514,117
See accompanying notes to parent company financial statements
Pattern Energy Group Inc.
Note to Parent Company Financial Statements
Supplemental Notes
1	Summary of Significant Accounting Policies
Basis of Presentation
The condensed, standalone, financial statements of Pattern Energy Group Inc. (“parent company”) have been presented in accordance with Rule 12-04, Schedule I of Regulation S-X as the restricted net assets of the subsidiaries of the parent company exceed 25% of the consolidated net assets of the parent company and its subsidiaries. The condensed parent company financial statements have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) and should be read in conjunction with the parent company’s consolidated financial statements and the accompanying notes thereto.
Investments
For purposes of these financial statements, the parent company’s wholly owned and majority owned subsidiaries are recorded based on its proportionate share of the subsidiaries’ assets. The parent company’s share of net income of its unconsolidated subsidiaries is included in income using the equity method.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2014

Accounting Policies [Abstract]

Basis of Presentation and Principles of Consolidation

Basis of Presentation and Principles of Consolidation

The accompanying consolidated financial statements have been prepared in accordance with the accounting principles generally accepted in the United States (“U.S. GAAP”). They include the results of wholly-owned and partially-owned subsidiaries in which the Company has a controlling interest with all significant intercompany accounts and transactions eliminated.

Use of Estimates

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates, and such differences may be material to the consolidated financial statements.

Reclassification

Reclassification

Certain prior period balances have been reclassified to conform to current period presentation of the Company’s consolidated financial statements and accompanying notes. Such reclassifications have no effect on previously reported balance sheet subtotals, results of operations or retained earnings.

Unaudited Pro Forma Income Tax

Unaudited Pro Forma Income Tax

In order to present the tax effect of the Contribution Transactions, the Company has presented a 2012 pro forma income tax provision as if the Contribution Transactions occurred effective January 1, 2012 and as if the Company were under control of a Subchapter C-Corporation for U.S. federal income tax purposes.

Variable Interest Entities

Variable Interest Entities

ASC 810, Consolidation of Variable Interest Entities, defines the criteria for determining the existence of Variable Interest Entities (“VIEs”) and provides guidance for consolidation. The Company consolidates VIEs where the Company is the primary beneficiary. The primary beneficiary of a VIE is the party that has the power to direct the activities that most significantly impact the performance of the entity and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the entity.

Investments or joint ventures in which the Company does not have a majority ownership interest and are not VIEs for which the Company is considered the primary beneficiary are accounted for using the equity method. These amounts are included in unconsolidated investments in the consolidated balance sheets.

Acquisitions

Acquisitions

Business Combinations

When we acquire a controlling interest, the purchase is accounted for using the acquisition method, and the fair value of purchase consideration is allocated to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values. The excess, if any, of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. Conversely, the excess, if any, of the net fair values of identifiable assets and liabilities over the fair value of purchase consideration is recorded as gain. Such valuations require management to make significant estimates and assumptions, especially with respect to intangible assets. These estimates and assumptions are inherently uncertain, and as a result, actual results may differ from estimates. Significant estimates include, but are not limited to, future expected cash flows, useful lives and discount rates. During the measurement period, which is one year from the acquisition date, we may record adjustments to the assets acquired and liabilities assumed, with a corresponding offset to either goodwill or gain, depending on whether the fair value of purchase consideration is in excess of or less than net assets acquired. Upon the conclusion of the measurement period, any subsequent adjustments are recorded to earnings.

Equity Method Investments

Equity Method Investments

When the Company acquires a noncontrolling interest the investment is accounted for using the equity method of accounting and is initially recognized at cost.

Noncontrolling Interests

Noncontrolling Interests

Noncontrolling interests represent the portion of the Company’s net (loss) income, net assets and comprehensive (loss) income that is not allocable to the Company and is calculated based on ownership percentage, for certain projects.

For the noncontrolling interests in the Company’s Gulf Wind, Panhandle 1 and Panhandle 2 projects, the Company has determined that the operating partnership agreements do not allocate economic benefits pro rata to its two classes of investors and the appropriate methodology for calculating the noncontrolling interest balance that reflects the substantive profit sharing arrangement is a balance sheet approach using the hypothetical liquidation at book value (“HLBV”) method.

Under the HLBV method, the amounts reported as noncontrolling interest in the consolidated balance sheets and consolidated statements of operations represent the amounts the third party would hypothetically receive at each balance sheet reporting date under the liquidation provisions of the operating partnership agreement assuming the net assets of Gulf Wind, Panhandle 1 and Panhandle 2 were liquidated at recorded amounts determined in accordance with U.S. GAAP and distributed to the investors. The third-party interest in the results of operations of Gulf Wind, Panhandle 1 and Panhandle 2 and the Company’s net (loss) income and comprehensive (loss) income is determined as the difference in noncontrolling interests in the consolidated balance sheets at the start and end of each reporting period, after taking into account any capital transactions between Gulf Wind, Panhandle 1, Panhandle 2 and the third party. The noncontrolling interest balances in Gulf Wind, Panhandle 1 and Panhandle 2 are reported as a component of equity in the consolidated balance sheets.

Foreign Currency Translation

Foreign Currency Translation

The assets and liabilities of foreign subsidiaries, where the local currency is the functional currency, are translated from their respective functional currencies into U.S. dollars at the rates in effect at the balance sheet date and revenue and expense amounts are translated at average rates during the period, with resulting foreign currency translation adjustments recorded in other comprehensive (loss) income, net of tax, in the accompanying consolidated statements of stockholders’ equity and comprehensive (loss) income. Where the U.S. dollar is the functional currency, re-measurement adjustments are recorded in other income, net in the accompanying consolidated statements of operations.

Gains and losses realized from transactions, including related party balances not considered permanent investments, that are denominated in currencies other than an entity’s functional currency are included in other income, net in the accompanying consolidated statements of operations.

Concentrations of Credit Risk

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, trade receivables and derivative assets. The Company places its cash and cash equivalents with high quality institutions.

The Company sells electricity and environmental attributes, including renewable energy credits, primarily to creditworthy utilities under long-term, fixed-priced power purchase agreements (“PPAs”) and, in some cases, through individual renewable energy credits sale agreements. During the year ended December 31, 2014, Standard & Poor’s Rating Services (“S&P”) and Moody’s Investor Service (“Moody’s”) downgraded the credit rating of the Puerto Rico Electric Power Authority (“PREPA”) from BBB and Baa3 to CCC and Caa3, respectively. On December 31, 2014, the amount of trade receivables due from PREPA was $2.5 million. As of March 2, 2015, PREPA was current with respect to payments due under the PPA and the next payment will be due from PREPA under the PPA on approximately March 19, 2015.

The table below presents significant customers who accounted for the following percentages of total revenues and the related maximum amount of credit loss based on their percentages of total trade receivables as of December 31, 2014:

Year ended December 31,

2014

2013

2012

Revenue

Trade

Revenue

Trade

Revenue

Trade

Receivables

Receivables

Receivables

San Diego Gas & Electric

22.09

%

14.13

%

16.31

%

26.21

%

0.17

%

9.09

%

Manitoba Hydro

14.47

%

9.39

%

16.69

%

17.18

%

30.23

%

14.08

%

Electric Reliability Council of Texas

14.34

%

15.93

%

11.59

%

2.59

%

17.24

%

3.41

%

NV Energy, Inc.

11.07

%

9.98

%

11.57

%

6.54

%

8.82

%

29.16

%

Pacific Gas & Electric

10.93

%

9.54

%

13.77

%

14.47

%

21.79

%

13.81

%

The Company’s interest rate derivative assets are placed with counterparties that are creditworthy institutions. An additional derivative asset was generated from Credit Suisse Energy LLC, the counterparty to a 10-year fixed-for-floating swap related to annual electricity generation at the Company’s Gulf Wind project. The Company’s reimbursements for prepaid interconnection network upgrades are with large creditworthy utility companies.

Fair Value of Financial Instruments

Fair Value of Financial Instruments

ASC 820, Fair Value Measurements, defines fair value as the price at which an asset could be exchanged or a liability transferred in an orderly transaction between knowledgeable, willing parties in the principal or most advantageous market for the asset or liability. Where available, fair value is based on observable market prices or derived from such prices. Where observable prices or inputs are not available, valuation models are applied.

These valuation techniques involve some level of management estimation and judgment, the degree of which is dependent on the price transparency for the instruments or market and the instruments’ complexity. See Note 12 on Fair Value Measurements.

U.S. Treasury Grants

U.S. Treasury Grants

The Company received U.S. Treasury grants on certain wind power projects as defined under Section 1603 of the American Recovery and Reinvestment Act of 2009, as amended by the Tax Relief Unemployment Insurance Reauthorization and Job Creation Act of December 2010, upon approval by the U.S. Treasury Department. The Company records the U.S. Treasury grant proceeds as a deduction from the carrying amount of the related asset which results in a reduction of depreciation expense over the life of the asset. The Company records a catch-up adjustment in the period in which the grant is approved to recognize the portion of the grant that proportionally matches the depreciation for the period between the date of placement in service of the wind power project and approval by the U.S. Treasury Department. See Note 5 on Property, Plant and Equipment.

Cash and Cash Equivalents

Cash and Cash Equivalents

Cash and cash equivalents consist of all cash balances and highly-liquid investments with original maturities of three months or less. The Company maintains cash and cash equivalents, which consist principally of demand deposits with high credit quality financial institutions. The Company has exposure to credit risk to the extent cash and cash equivalent balances, including restricted cash, exceed amounts covered by federal deposit insurance. The Company believes that its credit risk is immaterial.

Restricted Cash

Restricted Cash

Restricted cash consists of cash balances which are restricted as to withdrawal or usage and includes cash to collateralize bank letters of credit related primarily to interconnection rights, PPAs and for certain reserves required under the Company’s loan agreements.

Trade Receivables

Trade Receivables

The Company’s trade receivables are generated by selling energy and renewable energy credits in the California, Texas, Nevada, Manitoba (Canada), Puerto Rico and Chilean energy markets. The Company believes that all amounts are collectible and an allowance for doubtful accounts is not required as of December 31, 2014 and 2013.

Reimbursable Interconnection Costs

Reimbursable Interconnection Costs

The Company may, from time to time, pay to construct interconnection network upgrades on behalf of the Company’s utility customers. The interconnection upgrades are owned by each utility customer who will reimburse the Company with interest when the project reaches commercial operations.

Turbine Advances

Turbine Advances

Turbine advances represent amounts advanced to turbine suppliers for the manufacture of wind turbines in accordance with turbine supply agreements for the Company’s wind power projects and for which the Company has not taken title. Turbine advances are reclassified to construction in progress when the Company takes legal title to the related turbines and are reclassified to property, plant and equipment when the project achieves commercial operation. Depreciation does not commence until projects enter commercial operation and turbine assets are placed in service.

Deferred Development Costs

Deferred Development Costs

Deferred development costs represent the accumulated costs of initial permitting, environmental reviews, land rights and obligations and preliminary design and engineering work. The Company expenses all project development costs until a project is determined to be technically feasible and likely to achieve commercial success. Upon commencement of construction, deferred development costs are recorded as a component of construction in progress. Upon achievement of commercial operation, construction in progress, which includes deferred development costs, is reclassified to property, plant and equipment.

Construction in Progress

Construction in Progress

Construction in progress represents the accumulated costs of projects in construction. Construction costs include turbines for which the Company has taken legal title, civil engineering, electrical and other related costs. Other capitalized costs include reclassified deferred development costs, amortization of intangible assets, amortization of deferred financing costs, capitalized interest and other costs required to place a project into commercial operation. Construction in progress is reclassified to property, plant and equipment when the project achieves commercial operation.

Finite-Lived Intangible Assets

Finite-Lived Intangible Assets

Finite-lived intangible assets relate to easements and land options and mining rights. The Company amortizes finite-lived intangible assets using the straight-line method over the term of their estimated useful lives, which represents the term of the easements and land option and mining rights agreements, ranging from eleven months to twenty years. The Company periodically evaluates whether events or changes in circumstances have occurred that indicate the carrying amount of finite-lived intangible assets may not be recoverable, or information indicates that impairment may exist.

Property, Plant and Equipment

Property, Plant and Equipment

Property, plant and equipment represents the costs of completed and operational projects transferred from construction in progress, as well as land, computer equipment and software, furniture and fixtures, leasehold improvements and other equipment. Property, plant and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated using the straight-line method over the respective assets’ useful lives. Wind farms are depreciated over twenty years and the remaining assets are depreciated over two to five years. Land is not depreciated. Improvements to property, plant and equipment deemed to extend the useful economic life of an asset are capitalized. Repair and maintenance costs are expensed as incurred.

Accounting for Impairment of Long-Lived Assets

Accounting for Impairment of Long-Lived Assets

The Company periodically evaluates long-lived assets for potential impairment whenever events or changes in circumstances have occurred that indicate that impairment may exist, or the carrying amount of the long-lived asset may not be recoverable. An impairment loss is recognized only if the carrying amount of a long-lived asset is not recoverable based on its estimated future undiscounted cash flows. An impairment loss is calculated based on the excess of the carrying value of the long-lived asset over the fair value of such long-lived asset , with the fair value determined based on an estimate of discounted future cash flows. Through December 31, 2014, no impairment charges have been recorded.

Derivatives

Derivatives

The Company recognizes its derivative instruments as assets or liabilities at fair value in the consolidated balance sheets, unless the derivative instruments qualify for the “normal purchase normal sale” (“NPNS”) scope exception to derivative accounting. Accounting for changes in the fair value (i.e., gains or losses) of a derivative instrument depends on whether it has been designated as part of a hedging relationship and on the type of hedging relationship.

For derivative instruments that are designated as cash flow hedges, the effective portion of change in fair value of the derivative is reported as a component of other comprehensive (loss) income (“OCI”). Changes in the fair value of these derivatives are subsequently reclassified into earnings in the period that the hedged transaction affects earnings. The ineffective portion of change in fair value is recorded as a component of net (loss) income on the consolidated statement of operations. For undesignated derivative instruments, the change in fair value is reported as a component of net (loss) income on the consolidated statement of operations. Certain of our electricity price derivatives that qualify for the NPNS scope exception to derivative accounting are accounted for under the accrual method of accounting.

The Company enters into derivative transactions for the purpose of reducing exposure to fluctuations in interest rates and electricity prices. The Company has entered into interest rate swaps, an interest rate cap and an electricity price derivative.

Interest rate swaps are instruments used to fix the interest rate on variable interest rate debt.

An interest rate cap is an instrument that is used to reduce exposure to future variable interest rates when the related debt is expected to be refinanced.

The Company entered into an electricity price arrangement, which qualifies as a derivative, that fixes the price of approximately 58% of the electricity expected to be produced and sold by Gulf Wind through April 2019, and which reduces the Company’s exposure to spot electricity prices.

Deferred Financing Costs

Deferred Financing Costs

Financing costs incurred in connection with obtaining construction and term financing are deferred and amortized over the lives of the respective loans using the effective-interest method. Amortization of deferred financing costs is capitalized during construction and recorded as interest expense in the consolidated statements of operations following commencement of commercial operation.

Income Taxes

Income Taxes

Prior to October 2, 2013, the Company’s predecessor did not provide for income taxes as it was treated as a pass-through entity for U.S. federal and state income tax purposes, except for several specific circumstances involving its Canadian entities that are subject to Canadian income taxes, its Chilean entities, that are subject to Chilean income taxes, a U.S. entity that is subject to Puerto Rican taxes and a U.S. entity that became subject to U.S. income taxes in 2012. Federal and state income taxes were assessed at the owner level and each owner was liable for its own tax payments. Certain consolidated entities are corporations or have elected to be taxed as corporations. In these circumstances, income tax was accounted for under the asset and liability method.

Subsequent to October 2, 2013, following the Contribution Transactions, the Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company recognizes deferred tax assets to the extent that it believes these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning and results of recent operations. If the Company determines that it would be able to realize its deferred tax assets in the future in excess of their net recorded amount, it would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes. The Company records uncertain tax positions in accordance with ASC 740 on the basis of a two-step process whereby (1) it determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, it recognizes the largest amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company has a policy to classify interest and penalties associated with uncertain tax positions together with the related liability, and the expenses incurred related to such accruals, if any, are included in the provision for income taxes.

Contingent Liabilities

Contingent Liabilities

The Company’s contingent liabilities represent deferred and contingent obligations related to projects acquired through business combinations and contingent bonuses payable to turbine service and maintenance providers associated with long-term turbine service and maintenance arrangements. Contingent liabilities are reported at fair value at each reporting period.

Asset Retirement Obligation

Asset Retirement Obligation

The Company records asset retirement obligations for the estimated costs of decommissioning turbines, removing above-ground installations and restoring sites, at the time when a contractual decommissioning obligation materializes. The Company records accretion expense, which represents the increase in the asset retirement obligations, over the remaining or operational life of the associated wind project. Accretion expense is recorded as cost of revenue in the statement of operations using accretion rates based on credit adjusted risk-free interest rates.

Revenue Recognition

Revenue Recognition

The Company sells the electricity it generates under the terms of power sale agreements (“PSAs”) or at spot-market prices. Revenue is recognized based upon the amount of electricity delivered at rates specified under the contracts, assuming all other revenue recognition criteria are met. The Company evaluates its PSAs to determine whether they are in substance leases or derivatives and, if applicable, recognizes revenue pursuant to ASC 840, Leases and ASC 815, Derivatives and Hedging, respectively. As of December 31, 2014, there were no PSAs that are accounted for as leases or derivatives and revenue is recognized on an accrual basis.

The Company also generates renewable energy credits as it produces electricity. Certain of these energy credits are sold independently in an open market and revenue is recognized at the time title to the energy credits is transferred to the buyer.

The Company acquired a ten-year energy derivative instrument as part of its acquisition of Gulf Wind in 2010, which fixes approximately 58% of the project’s expected electricity generation through April 2019. The energy derivative instrument reduces exposure to changes in commodity prices by allowing the Company to lock in a fixed price per MWh for a specified amount of annual electricity generation. The monthly settlement amounts under the energy hedge are accounted for as energy derivative settlements in the consolidated statements of operations. The change in the fair value of the energy hedge is classified as unrealized (loss) gain on energy derivative revenue in the consolidated statements of operations.

The Company recognizes revenue for warranty settlements and liquidated damages from turbine manufacturers in other revenue upon resolution of outstanding contingencies. Any cash receipts for amounts subject to future adjustment or repayment are deferred in other liabilities until the final settlement amount is considered fixed and determinable.

Cost of Revenue

Cost of Revenue

The Company’s cost of revenue is comprised of direct costs of operating and maintaining its wind project facilities, including labor, turbine service arrangements, land lease royalties, depreciation, accretion, property taxes and insurance.

Stock-Based Compensation

Stock-Based Compensation

The Company accounts for stock-based compensation related to stock options granted to employees by estimating the fair value of the stock-based awards using the Black-Scholes option-pricing model. The fair value of the stock options granted is amortized over the applicable vesting period. The Black-Scholes option pricing model includes assumptions regarding dividend yields, expected volatility, expected option term, expected forfeiture rate and risk-free interest rates. The Company estimates expected volatility based on the historical volatility of comparable publicly traded companies for a period that is equal to the expected term of the options. The risk-free interest rate is based on the U.S. treasury yield curve in effect at the time of grant for a period commensurate with the estimated expected term of the stock option. The expected term of options granted is derived using the “simplified” method as allowed under the provisions of the ASC 718, Compensation—Stock Compensation, and represents the period of time that options granted are expected to be outstanding.

The Company accounts for stock-based compensation related to restricted stock award grants by amortizing the fair value of the restricted stock award grants, which is the grant date market price, over the applicable vesting period.

Stock-based compensation expense is recorded as a component of general and administrative expenses in the Company’s consolidated statements of operations.

Comprehensive (Loss) Income

Comprehensive (Loss) Income

Comprehensive (loss) income consists of net (loss) income and other comprehensive (loss) income, net of tax. Other comprehensive (loss) income, net of tax included in accumulated other comprehensive (loss) income in the accompanying consolidated statements of stockholders’ equity, is comprised of changes in foreign currency translation adjustments and changes in the fair value of derivatives designated as hedges.

Segment Data

Segment Data

Operating segments are defined as components of a company about which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The Company’s chief operating decision maker is the chief executive officer. Based on the financial information presented to and reviewed by the chief operating decision maker in deciding how to allocate the resources and in assessing the Company’s performance, the Company has determined its wind projects represent individual operating segments with similar economic characteristics that meet the criteria for aggregation into a single reporting segment for financial statement purposes.

Recently Issued Accounting Standards

Recently Issued Accounting Standards

In February 2015, the Financial Accounting Standards Board (“FASB”) issued ASU 2015-02, “Consolidation: Amendments to the Consolidation Analysis” to modify the analysis that companies must perform in order to determine whether a legal entity should be consolidated. ASU 2015-02 simplifies current guidance by reducing the number of consolidation models; eliminating the risk that a reporting entity may have to consolidate based on a fee arrangement with another legal entity; placing more weight on the risk of loss in order to identify the party that has a controlling financial interest; reducing the number of instances that related party guidance needs to be applied when determining the party that has a controlling financial interest; and changing rules for companies in certain industries that ordinarily employ limited partnership or VIE structures. ASU 2015-02 is effective for public companies beginning after December 15, 2015 and interim periods within those fiscal periods. Early adoption on a modified retrospective or full retrospective basis is permitted. The Company is currently assessing the future impact of this update on its consolidated financial statements.

In November 2014, the FASB issued ASU 2014-17, “Business Combinations: Pushdown Accounting”, which provides an entity with an option to apply pushdown accounting in its separate financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity. The amendments in ASU 2014-17 are effective November 18, 2014. After the effective date, an acquired entity can make an election to apply the guidance to future change-in-control events or to its most recent change-in-control event. However, if the financial statements for the period in which the most recent change-in-control event occurred already have been issued or made available to be issued, the application of this guidance would be a change in accounting principle. The Company does not anticipate that the adoption of this update will have a material impact on its consolidated financial statements.

In November 2014, the FASB issued ASU 2014-16, “Derivatives and Hedging – Determining Whether the Host Contract in a Hybrid Financial Instrument Issued in the Form of a Share is More Akin to Debt or to Equity”, which provides clarification on how current U.S. GAAP should be interpreted in evaluating the economic characteristics and risks of a host contract in a hybrid financial instrument that is issued in the form of a share. ASU 2014-16 is effective for interim and annual periods beginning after December 15, 2015, with early adoption permitted. The Company is currently assessing the future impact of this update on its consolidated financial statements.

In August 2014, the FASB issued Accounting Standards Update (“ASU”) 2014-15, “Presentation of Financial Statements – Going Concern: Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”, which requires an entity’s management to evaluate whether there is substantial doubt about the entity’s ability to continue as a going concern and to provide related footnote disclosures. ASU 2014-15 is effective for interim and annual periods beginning after December 15, 2016, with early adoption permitted for interim and annual reporting periods for which the financial statements have not been previously issued. The Company does not anticipate that the adoption of this update will have a material impact on its consolidated financial statements.

In June 2014, the FASB issued ASU 2014-12, “Compensation – Stock Compensation” which requires an entity to treat a performance target that affects vesting that could be achieved after an employee completes the requisite service period as a performance condition. The performance target should not be reflected in estimating the grant-date fair value of the award. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attributable to the period(s) for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. ASU 2014-12 is effective for interim and annual periods beginning after December 15, 2015, with early adoption permitted either prospectively or retrospectively to all prior periods presented. The Company does not anticipate that the adoption of this update will have a material impact on its financial condition, results of operations or cash flows.

In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers”. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer, as opposed to recognizing revenue when the risks and rewards transfer to the customer under the existing revenue guidance. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. The guidance permits companies to either apply the requirements retrospectively to all prior periods presented, or apply the requirements in the year of adoption, through a cumulative adjustment. The Company is currently assessing the future impact of this update on its consolidated financial statements.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Schedule of Percentages of Total Revenues and Related Maximum Amount of Credit Loss of Total Trade Receivables from Significant Customers	The table below presents significant customers who accounted for the following percentages of total revenues and the related maximum amount of credit loss based on their percentages of total trade receivables as of December 31, 2014:
		Year ended December 31,
		2014						2013						2012
		Revenue			Trade			Revenue			Trade			Revenue			Trade
					Receivables						Receivables						Receivables
	San Diego Gas & Electric		22.09	%		14.13	%		16.31	%		26.21	%		0.17	%		9.09	%
	Manitoba Hydro		14.47	%		9.39	%		16.69	%		17.18	%		30.23	%		14.08	%
	Electric Reliability Council of Texas		14.34	%		15.93	%		11.59	%		2.59	%		17.24	%		3.41	%
	NV Energy, Inc.		11.07	%		9.98	%		11.57	%		6.54	%		8.82	%		29.16	%
	Pacific Gas & Electric		10.93	%		9.54	%		13.77	%		14.47	%		21.79	%		13.81	%

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2014
E1 Arrayan [Member]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The consolidated fair value of the assets acquired and liabilities assumed in connection with the AEI El Arrayán acquisition are as follows (in thousands):
		Consolidated
		interest
		June 25, 2014
	Cash and cash equivalents	$	713
	Trade receivables		3,829
	VAT receivable		17,031
	Prepaid expenses and other current assets		174
	Restricted cash, non-current		10,392
	Property, plant and equipment		341,417
	Intangible assets		1,121
	Net deferred tax assets		5,455
	Accounts payable and other accrued liabilities		(6,830	)
	Accrued construction costs		(9,495	)
	Accrued interest		(2,592	)
	Derivative liabilities, current		(1,942	)
	Current portion of long-term debt		(16,586	)
	Long-term debt		(209,295	)
	Derivative liabilities, non-current		(501	)
	Asset retirement obligation		(2,354	)
	Net deferred tax liabilities		(13,001	)
	Total consideration		117,536
	Less: non-controlling interest		(35,259	)
	Controlling interest	$	82,277
Schedule of Supplemental Pro Forma Data	The unaudited pro forma data should not be considered representative of the Company’s future financial condition or results of operations.
		Year ended
		December 31,
	Unaudited pro forma data (in thousands)	2014			2013
	Pro forma total revenue	$	268,116		$	201,573
	Pro forma total expenses		326,990			192,762
	Pro forma net (loss) income		(58,874	)		8,811
	Less: pro forma net loss attributable to noncontrolling interest		(8,662	)		(7,176	)
	Pro forma net (loss) income attributable to controlling interest	$	(50,212	)	$	15,987
Panhandle 1 [Member]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The consolidated fair value of the assets acquired and liabilities assumed in connection with the Panhandle 1 acquisition are as follows (in thousands):
		June 30, 2014
	Cash and cash equivalents	$	1,038
	Trade receivables		1,850
	Prepaid expenses and other current assets		71
	Restricted cash, non-current		14,293
	Property, plant and equipment		332,953
	Accounts payable and other accrued liabilities		(148	)
	Accrued construction costs		(12,806	)
	Related party payable		(44	)
	Asset retirement obligation		(2,557	)
	Total consideration before non-controlling interest		334,650
	Less: tax equity noncontrolling interest contributions		(210,250	)
	Total consideration after non-controlling interest	$	124,400
Logan's Gap [Member]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The consolidated fair value of the assets acquired and liabilities assumed in connection with the Logan’s Gap acquisition are as follows (in thousands):
		December 19, 2014
	Cash and cash equivalents	$	2
	Restricted cash, current		5,003
	Prepaid expenses and other current assets		1,722
	Deferred financing costs, current		2,117
	Construction in progress		23,770
	Property, plant and equipment		116
	Other assets		80
	Accrued construction costs		(4,733	)
	Current portion of contingent liabilities		(7,975	)
	Related party payable		(5,003	)
	Total consideration	$	15,099
Panhandle 2 [Member]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The consolidated fair value of the assets acquired and liabilities assumed in connection with the Panhandle 2 acquisition are as follows (in thousands):
		November 10, 2014
	Cash and cash equivalents	$	240
	Trade receivables		1,156
	Prepaid expenses and other current assets		28,997
	Property, plant and equipment		315,109
	Accrued construction costs		(24,197	)
	Related party payable		(121	)
	Short-term debt		(195,351	)
	Asset retirement obligation		(2,003	)
	Total consideration	$	123,830
E1 Arrayan, Panhandle 1, Panhandle 2 and Logans Gap [Member]
Schedule of Amounts Included in Consolidated Statements of Operations	The following table presents the amounts included in the consolidated statements of operations for AEI El Arrayán, Panhandle 1, Panhandle 2 and Logan’s Gap since their respective dates of acquisition:
		Year ended
		December 31,
	Unaudited data (in thousands)	2014
	Total revenue	$	30,841
	Total expenses		41,232
	Net loss		(10,391	)
	Less: net loss attributable to noncontrolling interest		(6,673	)
	Net loss attributable to controlling interest	$	(3,718	)

Prepaid_expenses_and_other_cur1

Prepaid expenses and other current assets (Tables)	12 Months Ended
	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Components of Prepaid Expenses and Other Current Assets	The following table presents the components of prepaid expenses and other current assets (in thousands):
		December 31,
		2014		2013
	Prepaid expenses	$	15,275	$	10,132
	Prepaid construction costs		5,155		—
	Sales tax		786		50
	Other current assets:
	Deposit for letters of credit		3,425		—
	Deferred equity issuance costs		2,331		—
	Other		982		1,233
	Prepaid expenses and other current assets	$	27,954	$	11,415

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	The following presents the categories within property, plant and equipment (in thousands):
		December 31,
		2014			2013
	Operating wind farms	$	2,624,640		$	1,652,119
	Furniture, fixtures and equipment		4,366			3,785
	Land		141			16
	Subtotal		2,629,147			1,655,920
	Less: accumulated depreciation		(278,291	)		(179,778	)
	Property, plant and equipment, net	$	2,350,856		$	1,476,142

Unconsolidated_Investments_Tab

Unconsolidated Investments (Tables)	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Projects Accounted under Equity Method of Accounting	The following presents projects that are accounted for under the equity method of accounting (in thousands):
								Percentage of Ownership
		December 31,						December 31,
		2014			2013			2014			2013
	South Kent	$	17,360		$	59,488			50	%		50	%
	Grand		11,719			26,464			45	%		45	%
	El Arrayán		—			21,103			N/A			31.5	%
	Unconsolidated investments	$	29,079		$	107,055
Summary of Aggregated Balance Sheets and Operating Results	The following summarizes the aggregated balance sheets of El Arrayán as of December 31, 2014 and 2013, and its operating results for the period from January 1, 2014 to June 25, 2014 and the years ended December 31, 2013 and 2012, respectively (in thousands):
		December 31,
		2014			2013
	Current assets	$	—		$	16,362
	Non-current assets		—			260,187
	Total assets	$	—		$	276,549
	Current liabilities	$	—		$	9,224
	Non-current liabilities		—			197,597
	Total liabilities		—			206,821
	Total equity		—			69,728
	Total liabilities and equity	$	—		$	276,549
		December 31,
		2014			2013			2012
	Revenue	$	1,821		$	—		$	—
	Other (income) expense		3,083			941			384
	Net loss	$	(1,262	)	$	(941	)	$	(384	)

Accounts_payable_and_other_acc1

Accounts payable and other accrued liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Payables and Accruals [Abstract]
Components of Accounts Payable and Other Accrued Liabilities	The following table presents the components of accounts payable and other accrued liabilities (in thousands):
		December 31,
		2014		2013
	Accounts payable	$	673	$	168
	Other accrued liabilities		9,202		6,329
	Warranty settlement payments		639		2,187
	LTSA upgrades liability		680		—
	Land lease rent payable		2,115		953
	Payroll liabilities		4,453		2,162
	Property tax payable		4,625		3,490
	Sales tax payable		2,406		261
	Accounts payable and other accrued liabilities	$	24,793	$	15,550

Long_term_debt_Tables

Long term debt (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Schedule of Long Term Debt	The Company’s long term debt as of December 31, 2014 and 2013 is presented below (in thousands):
		December 31,						Interest Rate as of						Interest
								December 31,						Type
		2014			2013			2014			2013				Maturity
	Hatchet Ridge term loan	$	228,288		$	239,865			1.43	%		1.43	%	Imputed	December 2032
	Gulf Wind term loan		156,122			166,448			3.23	%		3.25	%	Variable	Mar-20
	St. Joseph term loan		189,472			215,330			5.88	%		5.88	%	Fixed	May-31
	Spring Valley term loan		167,261			173,110			2.62	%		2.63	%	Variable	Jun-30
	Santa Isabel term loan		112,609			115,721			4.57	%		4.57	%	Fixed	September 2033
	El Arrayan commercial term loan		99,665			—			2.92	%		N/A		Variable	Mar-29
	El Arrayan EKF term loan		109,630			—			5.56	%		N/A		Fixed	Mar-29
	Ocotillo commercial term loan		222,175			230,944			1.98	%		3	%	Variable	Aug-20
	Ocotillo development term loan		106,700			107,800			2.33	%		2.35	%	Variable	Aug-33
	Logan’s Gap construction loan		58,691			—			1.64	%		N/A		Variable	Dec-15
			1,450,613			1,249,218
	Less: current portion		(121,561	)		(48,851	)
		$	1,329,052		$	1,200,367
Summary of Principal Payments Due under Long Term Debt	The following are principal payments due under long-term debt as of December 31, 2014 (in thousands):
	For the year ending December 31,
	2015	$	121,561
	2016		65,877
	2017		67,277
	2018		72,750
	2019		83,613
	Thereafter		1,039,535
		$	1,450,613
Schedule of Commitment Fees Incurred and Interest Expense Recorded	Interest and commitment fees incurred, and interest expense recorded in the Company’s consolidated statements of operations are as follows (in thousands):
		Year ended December 31,
		2014			2013			2012
	Interest and commitment fees incurred	$	59,864		$	57,478		$	43,496
	Capitalized interest, commitment fees, and letter of credit fees		(2,856	)		(4,210	)		(10,259	)
	Letter of credit fees		4,377			3,530			720
	Amortization of financing costs		6,309			6,816			2,545
	Interest expense	$	67,694		$	63,614		$	36,502

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]
Reconciliation of Beginning and Ending Aggregate Carrying Amounts of Asset Retirement Obligations	The following table presents a reconciliation of the beginning and ending aggregate carrying amounts of asset retirement obligations as of December 31, 2014, 2013 and 2012 (in thousands):
		December 31,
		2014			2013			2012
	Beginning asset retirement obligations	$	20,834		$	19,056		$	10,342
	Additions during the year		7,195			767			7,971
	Foreign currency translation adjustment		(228	)		(172	)		59
	Accretion expense		1,471			1,183			684
	Ending asset retirement obligations	$	29,272		$	20,834		$	19,056

Derivative_Instruments_Tables

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments Classified as Assets (Liabilities)	Undesignated Derivative Instruments Classified as Assets (Liabilities):
					As of						Year ended
					Fair Market Value						YTD Gain (Loss)
	Derivative Type	Project	Quantity	Maturity	Current			Long-Term			Recognized into
				Dates	Portion			Portion			Income
	December 31, 2014
	Interest rate swaps	Ocotillo	6	6/30/30	$	(3,403	)	$	2,523		$	(11,339	)
	Interest rate cap	Gulf Wind	1	12/31/24		—			352			(329	)
	Energy derivative	Gulf Wind	1	4/30/19		18,506			45,969			(3,878	)
					$	15,103		$	48,844		$	(15,546	)
	December 31, 2013
	Interest rate swaps	Ocotillo	6	6/30/30	$	(3,899	)	$	14,358		$	15,367
	Interest rate cap	Gulf Wind	1	12/31/24		—			681			234
	Energy derivative	Gulf Wind	1	4/30/19		13,937			54,416			(11,272	)
					$	10,038		$	69,455		$	4,329
	December 31, 2012
	Interest rate swaps	Ocotillo	6	6/30/30	$	(1,980	)	$	(2,931	)	$	(4,909	)
	Interest rate cap	Gulf Wind	1	12/31/24		—			447			(44	)
	Energy derivative	Gulf Wind	1	4/30/19		17,177			62,448			(6,951	)
					$	15,197		$	59,964		$	(11,904	)
	Designated Derivative Instruments Classified as Assets (Liabilities):
					As of						Year ended
					Fair Market Value						YTD Gain (Loss)
	Derivative Type	Project	Quantity	Maturity	Current			Long-Term			Recognized in
				Dates	Portion			Portion			OCI
	December 31, 2014
	Interest rate swaps	Ocotillo	6	6/30/33	$	(1,917	)	$	525		$	(8,912	)
	Interest rate swaps	El Arrayan	3	3/31/32		(1,822	)		(3,338	)		(1,983	)
	Interest rate swaps	Gulf Wind	7	3/15/20		(4,719	)		(6,915	)		1,094
	Interest rate swaps	Spring Valley	2	6/28/30		(4,446	)		(7,214	)		(9,869	)
					$	(12,904	)	$	(16,942	)	$	(19,670	)
	December 31, 2013
	Interest rate swaps	Ocotillo	6	6/30/33	$	(2,105	)	$	9,625		$	10,434
	Interest rate swaps	Gulf Wind	7	3/15/20		(5,289	)		(7,439	)		9,398
	Interest rate swaps	Spring Valley	2	6/28/30		(4,878	)		3,087			17,043
					$	(12,272	)	$	5,273		$	36,875
	December 31, 2012
	Interest rate swaps	Ocotillo	6	6/30/33	$	(952	)	$	(1,962	)	$	(2,914	)
	Interest rate swaps	Gulf Wind	7	3/15/20		(5,558	)		(16,568	)		(1,835	)
	Interest rate swaps	Spring Valley	2	6/28/30		(4,972	)		(13,865	)		(6,421	)
					$	(11,482	)	$	(32,395	)	$	(11,170	)

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive (Loss) Income (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Summary of Accumulated Other Comprehensive (Loss) Income	The following table summarizes changes in the accumulated other comprehensive (loss) income balance by component:
					Effective Portion of			Proportionate
		Foreign			Change in Fair Value			Share of Equity
		Currency			of Derivatives			Investee’s OCI			Total
	Balances at January 1, 2012	$	(2,903	)	$	(32,707	)	$	—		$	(35,610	)
	Net current period other comprehensive income (loss)		2,749			(11,170	)		(1,475	)		(9,896	)
	Balances at December 31, 2012		(154	)		(43,877	)		(1,475	)		(45,506	)
	Net current period other comprehensive (loss) income		(8,309	)		36,875			2,473			31,039
	Grand acquisition		—			—			(2,910	)		(2,910	)
	Balances at December 31, 2013		(8,463	)		(7,002	)		(1,912	)		(17,377	)
	Net current period other comprehensive (loss) income		(10,875	)		(19,670	)		(5,991	)		(36,536	)
	Balances at December 31, 2014	$	(19,338	)	$	(26,672	)	$	(7,903	)	$	(53,913	)

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Financial Assets and (Liabilities) Required Fair Value Measurement on Recurring Basis	The Company’s financial assets and (liabilities) which require fair value measurement on a recurring basis are classified within the fair value hierarchy as follows (in thousands):
		Fair Value
		Level 1			Level 2			Level 3			Total
	December 31, 2014
	Interest rate swaps	$	—		$	(30,726	)	$	—		$	(30,726	)
	Interest rate cap		—			352			—			352
	Energy derivative		—			—			64,475			64,475
		$	—		$	(30,374	)	$	64,475		$	34,101
	December 31, 2013
	Interest rate swaps	$	—		$	3,460		$	—		$	3,460
	Interest rate cap		—			681			—			681
	Energy derivative		—			—			68,353			68,353
		$	—		$	4,141		$	68,353		$	72,494
Reconciliation of Contingent Liabilities and Energy Derivative Contract Measured at Fair Value	The following table presents a reconciliation of contingent liabilities and the energy derivative contract measured at fair value, in thousands, on a recurring basis using significant unobservable inputs for the years ended December 31, 2014, 2013 and 2012, respectively. There were no transfers between Level 2 and Level 3 during the periods presented.
		Contingent			Energy			Total
		Liabilities			Derivative
	Balance at December 31, 2011	$	(5,986	)	$	86,577		$	80,591
	Settlements		—			(19,644	)		(19,644	)
	Change in fair value, net of settlements		(2,015	)		12,692			10,677
	Balances at December 31, 2012		(8,001	)		79,625			71,624
	Settlements		8,001			(16,798	)		(8,797	)
	Change in fair value, net of settlements		—			5,526			5,526
	Balances at December 31, 2013		—			68,353			68,353
	Settlements		—			(13,524	)		(13,524	)
	Change in fair value, net of settlements		—			9,646			9,646
	Balances at December 31, 2014	$	—		$	64,475		$	64,475
Carrying Amounts and Fair Values of Company's Financial Liabilities	The following table presents the carrying amount and fair value, in thousands, and the fair value hierarchy of the Company’s financial liabilities that are not measured at fair value in the consolidated balance sheets as of December 31, 2014 and 2013, but for which fair value is disclosed.
		As reflected on			Fair Value
		the balance sheet			Level 1			Level 2			Level 3			Total
	31-Dec-14
	Long-term debt, including current portion	$	1,450,613		$	—		$	1,416,744		$	—		$	1,416,744
	31-Dec-13
	Long-term debt, including current portion	$	1,249,218		$	—		$	1,165,119		$	—		$	1,165,119

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Components of Provision for Income Taxes	The following table presents significant components of the provision for income taxes (in thousands):
		Year ended December 31,
		2014			2013			2012
	Current:
	Federal	$	—		$	—		$	—
	State		—			—			—
	Foreign		182			—			—
	Total current expense (benefit)		182			—			—
	Deferred:
	Federal		—			2,961			—
	State		—			—			—
	Foreign		2,954			1,585			(3,604	)
	Total deferred expense (benefit)		2,954			4,546			(3,604	)
	Total provision for income taxes	$	3,136		$	4,546		$	(3,604	)
Domestic and Foreign Components of Net Income (Loss) Before Income Tax (Benefit) Expense	The following table presents the domestic and foreign components of net income (loss) before income tax (benefit) expense (in thousands):
		Year ended December 31,
		2014			2013			2012
	U.S.	$	(34,788	)	$	4,022		$	(17,810	)
	Foreign		(2,075	)		10,596			830
	Total	$	(36,863	)	$	14,618		$	(16,980	)
Reconciliation of Statutory U.S Federal Income Tax Rate to Effective Tax Rate	The following table presents a reconciliation of the statutory U.S. federal income tax rate to the Company’s effective tax rate, as a percentage of income before taxes for the years ended December 31, 2014, 2013 and 2012:
		Year ended
		December 31,
		2014			2013			2012
	Computed tax at statutory rate		35	%		35	%		35	%
	Book/tax basis difference		—			—			27.2	%
	Partnership income not subject to taxes		—			—			(40.9	%)
	Adjustment for income in non-taxable entities allocable to noncontrolling interest		(7.6	%)		16.5	%		—
	Foreign rate differential		—			—			—
	Tax rate differential on pre-tax book income, other		5.6	%		2.1	%		—
	Local tax on branch profits/(losses)—Puerto Rico		1.6	%		13.1	%		—
	Permanent book/tax differences (domestic only)		(0.1	%)		(2.2	%)		—
	Valuation Allowance		(33.4	%)		187.2	%		—
	Deferred tax liability on Chilean shareholder liability due to tax regime change		(3.6	%)		—			—
	Change in tax rate due to change in Chilean tax regime		(6.2	%)		—			—
	Other		0.1	%		3.1	%		—
	ARRA Section 1603 grant-basis reduction deferred tax assets		—			(223.7	%)		—
	Effective income tax rate		(8.6	%)		31.1	%		21.3	%
Components of Deferred Tax Assets and Deferred Tax Liabilities	The following table presents significant components of the Company’s deferred tax assets and deferred tax liabilities as of December 31, 2014 and 2013 (in thousands):
		Year ended December 31,
		2014			2013			2012
	Deferred tax assets/(liabilities)—current:
	Accruals, prepaids and other current deferred tax assets and liabilities	$	(344	)	$	2,399		$	—
	Basis difference in derivatives		4,779			2,835			—
	Total gross deferred tax assets/(liabilities)		4,435			5,234			—
	Less: valuation allowance		(4,266	)		(4,661	)		—
	Total net deferred tax assets/(liabilities)—current	$	169		$	573		$	—
	Deferred tax assets/(liabilities)—non-current:
	Property, plant and equipment	$	(104,767	)	$	(36,548	)	$	(47,894	)
	Basis difference in foreign subsidiaries		37,626			40,097			—
	Partnership interest		994			(4,917	)		—
	Lease Hatchet Ridge		28,044			29,314			—
	Asset retirement obligation		5,216			4,649			—
	Equity method		—			3,794			—
	Unrealized loss on derivatives		—			(5,830	)		—
	Other temp differences		256			—
	Net operating loss carryforwards		130,248			61,441			45,302
	Other non current deferred tax assets and liabilities		(5,081	)		(4,595	)		(690	)
	Change in tax status		—			—			4,599
	Accruals not currently deductible		—			—			443
	Total gross deferred tax assets/(liabilities)—non-current		92,536			87,405			1,760
	Less: valuation allowance		(107,480	)		(95,318	)		(482	)
	Total net deferred tax assets/(liabilities)—non-current	$	(14,944	)	$	(7,913	)	$	1,278
	Total net deferred tax assets/(liabilities)	$	(14,775	)	$	(7,340	)	$	1,278

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Summary of Noncontrolling Interest Balances	Noncontrolling Interests
	The following table presents the noncontrolling interest balances, reported in stockholders’ equity in the consolidated balance sheets by project as of December 31, 2014 and 2013 (in thousands):
						Noncontrolling Ownership Percentage
		December 31,				December 31,
		2014		2013		2014			2013
	Gulf Wind	$	97,061	$	99,794		60	%		60	%
	El Arrayán		35,624		—		30	%		N/A
	Panhandle 1		205,333		—		21	%		N/A
	Panhandle 2		192,568		—		19	%		N/A
	Noncontrolling interest	$	530,586	$	99,794

Equity_Incentive_Award_Plan_Ta

Equity Incentive Award Plan (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Weighted Average Assumptions	The following weighted average assumptions were used:
		Year ended December 31,
		2014			2013
	Stock options:
	Risk-free interest rate		1.68	%		1.68	%
	Expected life (in years)		5.8			5.8
	Expected volatility		36	%		36	%
	Expected dividend yield		5.7			5.7
Summary of Stock Option Activity	The following table summarizes stock option activity under the 2013 Plan for the year ended December 31, 2014:
								Weighted Average
								Remaining
		Number of Options			Weighted Average			Contractual Life		Aggregate
		Outstanding			Exercise Price			(in years)		Instrinsic Value
	Outstanding at December 31, 2013		444,823		$	22
	Exercised		(14,861	)		22				$	108,191
	Outstanding at December 31, 2014		429,962		$	22			8.8	$	1,143,699
	Exercisable at December 31, 2014		170,434		$	22			8.8	$	453,354
	Vested and expected to vest as of December 31, 2014		429,962		$	22			8.8	$	1,143,699
Summary of Restricted Stock Awards Activity	The following table summarizes restricted stock awards activity under the 2013 Plan for the year ended December 31, 2014:
					Weighted Average			Aggregate
		Number of RSAs			Grant Date			Intrinsic
		Outstanding			Fair Value			Value
	Balance at December 31, 2013		76,262			22.53
	Granted		178,089			27.54
	Released		(81,914	)		26.64
	Forfeited		(2,174	)		27.03
	Repurchased for employee tax withholding		(24,531	)		26.44
	Balance at December 31, 2014		145,732		$	25.62		$	3,593,751

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Computations of Basic and Diluted Earnings (Loss) per Share	The computations for basic and diluted earnings (loss) per share are as follows:
		Year ended December 31,
		2014			2013
	Numerator for basic and diluted earnings (loss) per share:
	Net loss attributable to controlling interest	$	(31,290	)	$	(13,336	)
	Less: dividends declared		(56,976	)		(11,103	)
	Less: deemed dividends		(21,901	)		—
	Undistributed loss	$	(110,167	)	$	(24,439	)
	Denominator for basic and diluted loss per share:
	Weighted average number of shares:
	Class A common stock—basic		42,361,959			35,448,056
	Add dilutive effect of:
	Stock options		52,915			14,462
	Restricted stock awards		27,401			38,131
	Class B common stock		15,555,000			15,555,000
	Class A common stock—fully diluted		57,997,275			51,055,649
	Less: antidilutive securities
	Stock options		(52,915	)		(14,462	)
	Restricted stock awards		(27,401	)		(38,131	)
	Class B common stock		(15,555,000	)		(15,555,000	)
	Class A common stock—diluted (excluding antidilutive securities)		42,361,959			35,448,056
	Class B common stock—basic and diluted		15,555,000			15,555,000
	Calculation of basic and diluted earnings (loss) per share:
	Class A common stock:
	Dividends	$	1.34		$	0.31
	Undistributed loss		(1.90	)		(0.48	)
	Basic loss per share	$	(0.56	)	$	(0.17	)
	Class A common stock:
	Diluted loss per share	$	(0.56	)	$	(0.17	)
	Class B common stock:
	Deemed dividends	$	1.41		$	—
	Undistributed loss		(1.90	)		(0.48	)
	Basic and diluted loss per share	$	(0.49	)	$	(0.48	)
	Cash dividends declared per Class A common share	$	1.3		$	0.31
	Deemed dividends per Class B common share	$	1.41		$	—
As Previously Reported [Member]
Computations of Basic and Diluted Earnings (Loss) per Share	The following table presents the basic and diluted earnings (loss) per share as previously reported and as revised for the three and nine months ended September 30, 2014:
		Three months ended						Nine months ended
		September 30, 2014						September 30, 2014
		As Reported			As Revised			As Reported			As Revised
	Numerator for basic and diluted earnings (loss) per share:
	Net loss attributable to controlling interest	$	(7,208	)	$	(7,208	)	$	(10,898	)	$	(10,898	)
	Less: cash dividends declared on Class A common shares		(15,258	)		(15,258	)		(41,395	)		(41,395	)
	Less: deemed dividends on Class B common shares		(7,222	)		(7,222	)		(14,679	)		(14,679	)
	Net loss attributable to common stockholders	$	(29,688	)	$	(29,688	)	$	(66,972	)	$	(66,972	)
	Denominator for basic and diluted loss per share:
	Weighted average number of shares:
	Class A common stock—basic		40,980,989			46,317,932			38,342,998			41,022,962
	Add dilutive effect of:
	Stock options		133,197			133,197			112,252			112,252
	Restricted stock awards		191,451			191,451			191,451			191,451
	Class B common stock		15,555,000			15,555,000			15,555,000			15,555,000
	Class A common stock—fully diluted		56,860,637			62,197,580			54,201,701			56,881,665
	Less: antidilutive securities
	Stock options		(133,197	)		(133,197	)		(112,252	)		(112,252	)
	Restricted stock awards		(191,451	)		(191,451	)		(191,451	)		(191,451	)
	Class B common stock		(15,555,000	)		(15,555,000	)		—			—
	Class A common stock—diluted (excluding antidilutive securities)		40,980,989			46,317,932			53,897,998			56,577,962
	Class B common stock—basic and diluted		15,555,000			15,555,000			15,555,000			15,555,000
	Calculation of basic and diluted earnings (loss) per share:
	Class A common stock:
	Dividends	$	0.37		$	0.33		$	1.08		$	1.01
	Undistributed loss		(0.53	)		(0.48	)		(1.24	)		(1.18	)
	Basic loss per share	$	(0.15	)	$	(0.15	)	$	(0.16	)	$	(0.17	)
	Class A common stock:
	Diluted loss per share	$	(0.15	)	$	(0.15	)	$	(0.20	)	$	(0.19	)
	Class B common stock:
	Deemed dividends	$	0.46		$	0.46		$	0.94		$	0.94
	Undistributed loss		(0.53	)		(0.48	)		(1.24	)		(1.18	)
	Basic and diluted loss per share	$	(0.06	)	$	(0.02	)	$	(0.30	)	$	(0.24	)
	Cash dividends declared per Class A common share	$	0.33		$	0.33		$	0.96		$	0.96
	Deemed dividends per Class B common share	$	0.46		$	0.46		$	0.94		$	0.94
	The following table presents the basic and diluted earnings (loss) per share as previously reported and as revised for the three and six months ended June 30, 2014:
		Three months ended						Six months ended
		June 30, 2014						June 30, 2014
		As Reported			As Restated			As Reported			As Restated
	Numerator for basic and diluted earnings (loss) per share:
	Net income (loss) attributable to controlling interest	$	11,199		$	11,199		$	(3,690	)	$	(3,690	)
	Less: cash dividends declared on Class A common shares		(14,981	)		(14,981	)		(26,138	)		(26,138	)
	Less: deemed dividends on Class B common shares		—			(7,457	)		—			(7,457	)
	Net loss attributable to common stockholders	$	(3,782	)	$	(11,239	)	$	(29,828	)	$	(37,285	)
	Denominator for earnings (loss) per share:
	Weighted average number of shares:
	Class A common stock—basic		41,174,697			41,174,697			38,331,595			38,331,595
	Add dilutive effect of:
	Stock options		107,979			107,979			100,814			100,814
	Restricted stock awards		227,543			227,543			227,543			227,543
	Class B common stock		15,555,000			15,555,000			15,555,000			15,555,000
	Class A common stock—fully diluted		57,065,219			57,065,219			54,214,952			54,214,952
	Less: antidilutive securities
	Stock options		—			—			—			(100,814	)
	Restricted stock awards		—			—			—			(227,543	)
	Class B common stock		—			(15,555,000	)		—			—
	Class A common stock—diluted (excluding antidilutive securities)		57,065,219			41,510,219			54,214,953			53,886,595
	Class B common stock—basic and diluted		15,555,000			15,555,000			15,555,000			15,555,000
	Calculation of basic and diluted earnings (loss) per share:
	Class A common stock:
	Dividends	$	0.36		$	0.36		$	0.68		$	0.68
	Undistributed loss		(0.07	)		(0.20	)		(0.55	)		(0.69	)
	Basic earnings (loss) per share	$	0.3		$	0.17		$	0.13		$	(0.01	)
Class A common stock:
Diluted earnings (loss) per share	$	0.2		$	0.16		$	(0.07	)	$	(0.07	)
Class B common stock:
Deemed dividends	$	—		$	0.48		$	—		$	0.48
Undistributed loss		(0.07	)		(0.20	)		(0.55	)		(0.69	)
Basic and diluted earnings (loss) per share	$	(0.07	)	$	0.28		$	(0.55	)	$	(0.21	)
Cash dividends declared per Class A common share	$	—		$	0.32		$	—		$	0.63
Deemed dividends per Class B common share	$	—		$	0.48		$	—		$	0.48
The following table presents the basic and diluted earnings (loss) per share as previously reported and as revised for the three months ended March 31, 2014:
	Three months ended
	March 31, 2014
	As Reported			As Restated
Numerator for basic and diluted earnings per share:
Net income (loss) attributable to controlling interest	$	(14,889	)	$	(14,889	)
Less: cash dividends declared on Class A common shares		(11,179	)		(11,179	)
Net loss attributable to common stockholders	$	(26,068	)	$	(26,068	)
Denominator for loss per share:
Weighted average number of shares:
Class A common stock—basic		35,533,166			35,533,166
Add dilutive effect of:
Stock options		95,219			95,219
Restricted stock awards		238,546			238,546
Class B common stock		15,555,000			15,555,000
Class A common stock—fully diluted		51,421,931			51,421,931
Less: antidilutive securities
Stock options		(95,219	)		—
Restricted stock awards		(238,546	)		—
Class B common stock		(15,555,000	)		—
Class A common stock—diluted (excluding antidilutive securities)		35,533,166			51,421,931
Class B common stock—basic and diluted		15,555,000			15,555,000
Calculation of basic and diluted loss per share:
Class A common stock:
Dividends	$	0.31		$	0.31
Undistributed loss		(0.51	)		(0.51	)
Basic loss per share	$	(0.20	)	$	(0.20	)
Class A common stock:
Diluted loss per share	$	(0.20	)	$	(0.29	)
Class B common stock:
Basic and diluted loss per share	$	(0.51	)	$	(0.51	)

Geographic_Information_Tables

Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Summary of Geographical Revenues and Assets	The table below provides information, by country, about the Company’s consolidated operations. Revenue is recorded in the country in which it is earned and assets are recorded in the country in which they are located (in thousands):
		Revenue						Property, Plant and Equipment, net
		Year ended December 31,						December 31,
		2014		2013		2012		2014		2013
	United States	$	201,408	$	161,505	$	73,089	$	1,784,219	$	1,210,319
	Canada		46,593		40,068		41,439		233,690		265,823
	Chile		17,492		—		—		332,947		—
	Total	$	265,493	$	201,573	$	114,528	$	2,350,856	$	1,476,142

Commitments_Contingencies_and_1

Commitments, Contingencies and Warranties (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Payments Related to Land Leases	The future minimum payments related to these leases as of December 31, 2014, are as follows (in thousands):
	For the year ending December 31,
	2015	$	5,971
	2016		5,406
	2017		5,412
	2018		5,418
	2019		5,425
	Thereafter		141,443
	Total	$	169,075
Schedule of Operations and Maintenance Commitments	The following table presents operations and maintenance commitments over the next five years (in thousands):
	For the year ending December 31,
	2015	$	40,118
	2016		44,583
	2017		44,387
	2018		38,746
	2019		36,707
	Thereafter		148,872
	Total	$	353,413

Related_Party_Transactions_Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Allocated Costs Included in Combined Statement of Operations	The table below presents allocated costs prior to October 2, 2013 and net bilateral management service cost reimbursements on and after October 2, 2013 included in the consolidated statements of operations (in thousands):
		December 31,
		2014			2013			2012
	Project expense	$	—		$	1,995		$	1,998
	Related party general and administrative		5,787			8,169			10,604
	Related party income		(2,612	)		(665	)		—
	Other income, net		—			(551	)		(210	)
	Total	$	3,175		$	8,948		$	12,392

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Summary of Quarterly Consolidated Statements of Operations	The following tables summarize the Company’s unaudited quarterly consolidated statements of operations for each of the eight quarters in the two year period ended December 31, 2014. The quarterly consolidated statements of operations data were prepared on a basis consistent with the audited consolidated financial statements included in Part III, Item 14, “Financial Statements and Supplementary Data” in this Annual Report on Form 10-K.
	Quarterly financial data in thousands, except per share data:
		Three months ended
		December 31,			September 30,			June 30,			March 31,
		2014			2014			2014			2014
	Revenue	$	79,418		$	71,519		$	65,007		$	49,549
	Gross profit	$	26,311		$	17,669		$	27,023		$	12,298
	Net (loss) income	$	(15,986	)	$	(9,281	)	$	7,167		$	(21,899	)
	Net (loss) income attributable to noncontrolling interest	$	4,406		$	(2,073	)	$	(4,032	)	$	(7,010	)
	Net (loss) income attributable to controlling interest	$	(20,392	)	$	(7,208	)	$	11,199		$	(14,889	)
	Basic (loss) earnings per share—Class A	$	(0.36	)	$	(0.15	)	$	0.17		$	(0.20	)
	Diluted (loss) earnings per share—Class A	$	(0.36	)	$	(0.15	)	$	0.16		$	(0.29	)
	Basic and diluted earnings (loss) per share—Class B	$	(0.23	)	$	(0.02	)	$	0.28		$	(0.51	)
	Cash dividends declared per Class A common share	$	0.34		$	0.33		$	0.32		$	0.31
	Deemed dividends on Class B common shares	$	0.46		$	0.46		$	0.48		$	—
		Three months ended
		December 31,			September 30,			June 30,			March 31,
		2013			2013			2013			2013
	Revenue	$	41,767		$	57,257		$	58,712		$	43,837
	Gross profit	$	4,729		$	21,471		$	26,222		$	8,294
	Net (loss) income	$	(19,376	)	$	4,244		$	43,988		$	(18,784	)
	Net (loss) income attributable to noncontrolling interest	$	(6,197	)	$	3,248		$	(359	)	$	(3,579	)
	Net (loss) income attributable to controlling interest	$	(13,179	)	$	996		$	44,347		$	(15,205	)
	Basic and diluted loss per share—Class A	$	(0.17	)		N/A			N/A			N/A
	Basic and diluted loss per share—Class B	$	(0.48	)		N/A			N/A			N/A

Organization_Additional_Inform

Organization - Additional Information (Detail) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	14-May-14	Oct. 02, 2013	Oct. 17, 2012	Sep. 24, 2013
Schedule Of Description Of Business [Line Items]
Preferred Stock, shares authorized	100,000,000
Common stock conversion basis	All of the outstanding Class B common stock automatically convert, on a one-for-one basis, into Class A shares. There are no other conversion rights attached to Class B common stock.
Prior period expense of entity	$28,320,000	$12,988,000	$11,636,000
Net proceeds from issuance of shares	286,757,000	317,926,000
Portion of net proceeds utilized as consideration	306,584,000	30,070,000
Class A Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock	62,088,306	35,531,720
Common stock, shares authorized	500,000,000	500,000,000
Net proceeds from issuance of shares				286,800,000
Number of shares purchased upon exercise of overallotment option					2,400,000
Common stock shares issued and sold				21,117,171
Class A Common Stock [Member] | Follow On Public Offering [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock				10,810,810
Class A Common Stock [Member] | IPO [Member]
Schedule Of Description Of Business [Line Items]
Shares issued in initial public offering					16,000,000
Net proceeds from issuance of shares					317,000,000
Class B Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Common stock conversion basis	One-to-one basis
Pattern Development [Member]
Schedule Of Description Of Business [Line Items]
Portion of net proceeds utilized as consideration					232,600,000
Number of wind power projects					8
Pattern Development [Member] | Projects in operation [Member]
Schedule Of Description Of Business [Line Items]
Number of wind power projects					6
Pattern Development [Member] | Projects under construction [Member]
Schedule Of Description Of Business [Line Items]
Number of wind power projects					2
Pattern Development [Member] | Gulf Wind [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	40.00%
Pattern Development [Member] | Distributable Cash Flow of Gulf Wind [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest					27.00%
Pattern Development [Member] | Pre IPO [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest				63.00%
Pattern Development [Member] | Secondary Offering [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest				35.00%
Pattern Development [Member] | Class A Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock					19,445,000
Number of shares purchased upon exercise of overallotment option				2,754,413
Common stock shares sold				10,306,361
Pattern Development [Member] | Class B Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock					15,555,000
Pattern Energy Unconsolidated [Member] | Maximum [Member]
Schedule Of Description Of Business [Line Items]
Prior period expense of entity		$10,000	$10,000
Pattern Renewables LP [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock						100
Pattern Energy Group Inc. [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest						100.00%
Common stock, shares authorized							620,000,000
Preferred Stock, shares authorized							100,000,000
Pattern Energy Group Inc. [Member] | Class A Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Common stock, shares authorized							500,000,000
Pattern Energy Group Inc. [Member] | Class B Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Common stock, shares authorized							20,000,000
Common stock conversion basis	One-for-one basis
Hatchet Ridge [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	100.00%
St Josephs [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	100.00%
Spring Valley [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	100.00%
Pattern Santa Isabel LLC [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	100.00%
Ocotillo [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	100.00%
Logan's Gap [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest	100.00%
Pattern Energy [Member] | Distributable Cash Flow of Gulf Wind [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest					40.00%
Corporate Joint Venture [Member] | Gulf Wind [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest					33.00%

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Significant Accounting Policies [Line Items]
Trade receivables	$35,759,000	$20,951,000
Asset impairment charges	0
Maximum tax benefit likely to be realized upon ultimate settlement, percentage	50.00%
Minimum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	2 years
Minimum [Member] | Land and mining rights [Member]
Significant Accounting Policies [Line Items]
Term of estimated useful lives	11 months
Maximum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	5 years
Maximum [Member] | Land and mining rights [Member]
Significant Accounting Policies [Line Items]
Term of estimated useful lives	20 years
Wind Farm [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	20 years
PREPA [Member]
Significant Accounting Policies [Line Items]
Trade receivables	$2,500,000
Gulf Wind [Member]
Significant Accounting Policies [Line Items]
Percentage of fixed price on electricity by derivative	58.00%
Credit Suisse [Member] | Gulf Wind [Member]
Significant Accounting Policies [Line Items]
Description of derivative swap	The counterparty to a 10-year fixed-for-floating swap related to annual electricity generation at the Company's Gulf Wind project.
Term of energy derivative instrument acquired	10 years

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Schedule of Percentages of Total Revenues and Related Maximum Amount of Credit Loss of Total Trade Receivables from Significant Customers (Detail) (Customer Concentration Risk [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
San Diego Gas and Electric [Member] | Trade Receivables [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	14.13%	26.21%	9.09%
Electric Reliability Council Of Texas [Member] | Trade Receivables [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	15.93%	2.59%	3.41%
NV Energy, Inc. [Member] | Trade Receivables [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	9.98%	6.54%	29.16%
Pacific Gas and Electric [Member] | Trade Receivables [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	9.54%	14.47%	13.81%
Revenue [Member] | San Diego Gas and Electric [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	22.09%	16.31%	0.17%
Revenue [Member] | Electric Reliability Council Of Texas [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	14.34%	11.59%	17.24%
Revenue [Member] | NV Energy, Inc. [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	11.07%	11.57%	8.82%
Revenue [Member] | Pacific Gas and Electric [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	10.93%	13.77%	21.79%
Manitoba [Member] | Hydro [Member] | Trade Receivables [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	9.39%	17.18%	14.08%
Manitoba [Member] | Revenue [Member] | Hydro [Member]
Concentration Risk [Line Items]
Concentrations of credit risk	14.47%	16.69%	30.23%

Acquisitions_Additional_Inform

Acquisitions - Additional Information (Detail) (USD $)	12 Months Ended			0 Months Ended		6 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 02, 2013	Jun. 25, 2014	Jun. 25, 2014	Dec. 19, 2014	Jun. 30, 2014	Nov. 10, 2014
						MW	MW	MW	MW
Business Acquisition [Line Items]
Carrying value of investment	$29,079,000	$107,055,000
Net gain on transactions	13,843,000	5,995,000	4,173,000
Contingent obligations payable	4,000,000
Contingent obligations paid	306,584,000	30,070,000
Pattern Development [Member]
Business Acquisition [Line Items]
Contingent obligations paid				232,600,000
E1 Arrayan [Member]
Business Acquisition [Line Items]
Acquired percentage of issued and outstanding of common stock					100.00%
Effective date of acquisition	25-Jun-14
Ownership interest					38.50%	38.50%
Indirect interest					31.50%	31.50%
Completed construction of wind power project					115	115
Total purchase price					45,300,000	45,300,000
Additional ownership interest acquired, percentage					38.50%	38.50%
Commercial operations start date	4-Jun-14
Fair value of equity interest at acquisition date					37,000,000
Fair value of equity value					117,500,000	117,500,000
Carrying value of investment	19,100,000
Net gain on transactions	17,900,000
Percentage of ownership					70.00%	70.00%
Transaction-related expenses	400,000
Non recurring transaction expenses	2,900,000
Non recurring transaction gain	17,900,000
Net loss in equity earnings						400,000
E1 Arrayan [Member] | Majority control [Member]
Business Acquisition [Line Items]
Ownership interest					70.00%	70.00%
Logan's Gap [Member]
Business Acquisition [Line Items]
Total purchase price							15,099,000
Transaction-related expenses	300,000
Contingent obligations payable	8,000,000						7,975,000
Logan's Gap [Member] | Pattern Development [Member]
Business Acquisition [Line Items]
Effective date of acquisition	19-Dec-14
Ownership interest							100.00%
Ownership interest							100.00%
Business acquisition acquired entity purchase price							15,100,000
Power generation capacity							164
Noncontrolling ownership interest							82.00%
Contingent obligations payable							8,000,000
Ownership interest							18.00%
Logan's Gap [Member] | Upon construction financing [Member]
Business Acquisition [Line Items]
Contingent obligations paid	4,000,000
Logan's Gap [Member] | Upon earlier of commercial operations [Member]
Business Acquisition [Line Items]
Contingent obligations payable	4,000,000
Panhandle 1 [Member]
Business Acquisition [Line Items]
Total purchase price								334,650,000
Net gain on transactions	500,000
Panhandle 1 [Member] | Pattern Development [Member]
Business Acquisition [Line Items]
Effective date of acquisition	30-Jun-14
Commercial operations start date	25-Jun-14
Ownership interest					79.00%	79.00%		79.00%
Business acquisition acquired entity purchase price					124,400,000	124,400,000		124,400,000
Power generation capacity					218			218
Panhandle 2 [Member]
Business Acquisition [Line Items]
Total purchase price									123,830,000
Commercial operations start date	7-Nov-14
Transaction-related expenses	200,000	600,000
Ownership interest									81.00%
Power generation capacity									182
Panhandle 2 [Member] | Pattern Development [Member]
Business Acquisition [Line Items]
Business acquisition acquired entity purchase price									$123,800,000
Class B Membership Interests [Member] | Panhandle 1 [Member] | Pattern Development [Member]
Business Acquisition [Line Items]
Ownership interest					100.00%	100.00%		100.00%
Class B Membership Interests [Member] | Panhandle 2 [Member]
Business Acquisition [Line Items]
Ownership interest									100.00%
Class B Membership Interests [Member] | Panhandle 2 [Member] | Pattern Development [Member]
Business Acquisition [Line Items]
Ownership interest									100.00%
Class A [Member] | Panhandle 1 [Member] | Investor [Member]
Business Acquisition [Line Items]
Ownership interest	100.00%
Noncontrolling ownership interest	21.00%
Class A [Member] | Panhandle 2 [Member] | Investor [Member]
Business Acquisition [Line Items]
Ownership interest									100.00%
Noncontrolling ownership interest									19.00%

Acquisitions_Schedule_of_Fair_

Acquisitions - Schedule of Fair Value of Assets Acquired and Liabilities Assumed (Detail) (USD $)	Dec. 31, 2014	Jun. 25, 2014	Jun. 30, 2014	Nov. 10, 2014	Dec. 19, 2014
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Current portion of contingent liabilities	($4,000)
E1 Arrayan [Member]
Business Acquisition [Line Items]
Total consideration		45,300
E1 Arrayan [Member] | Consolidated Interest [Member]
Business Acquisition [Line Items]
Cash and cash equivalents		713
Trade receivables		3,829
VAT receivable		17,031
Prepaid expenses and other current assets		174
Restricted cash, non-current		10,392
Property, plant and equipment		341,417
Intangible assets		1,121
Net deferred tax assets		5,455
Accounts payable and other accrued liabilities		-6,830
Accrued construction costs		-9,495
Accrued interest		-2,592
Derivative liabilities, current		-1,942
Current portion of long-term debt		-16,586
Long-term debt		-209,295
Derivative liabilities, non-current		-501
Asset retirement obligation		-2,354
Net deferred tax liabilities		-13,001
Total consideration		117,536
Less: tax equity noncontrolling interest contributions		-35,259
Total consideration after non-controlling interest		82,277
Panhandle 1 [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			1,038
Trade receivables			1,850
Prepaid expenses and other current assets			71
Restricted cash, non-current			14,293
Property, plant and equipment			332,953
Accounts payable and other accrued liabilities			-148
Accrued construction costs			-12,806
Related party payable			-44
Asset retirement obligation			-2,557
Total consideration			334,650
Less: tax equity noncontrolling interest contributions			-210,250
Total consideration after non-controlling interest			124,400
Panhandle 2 [Member]
Business Acquisition [Line Items]
Cash and cash equivalents				240
Trade receivables				1,156
Prepaid expenses and other current assets				28,997
Property, plant and equipment				315,109
Accrued construction costs				-24,197
Related party payable				-121
Short-term debt				-195,351
Asset retirement obligation				-2,003
Total consideration				123,830
Logan's Gap [Member]
Business Acquisition [Line Items]
Cash and cash equivalents					2
Restricted cash, current					5,003
Prepaid expenses and other current assets					1,722
Deferred financing costs, current					2,117
Construction in progress					23,770
Property, plant and equipment					116
Other assets					80
Accrued construction costs					-4,733
Current portion of contingent liabilities	-8,000				-7,975
Related party payable					-5,003
Total consideration					$15,099

Acquisitions_Schedule_of_Suppl

Acquisitions - Schedule of Supplemental Pro Forma Data (Detail) (E1 Arrayan, Panhandle 1, Panhandle 2 and Logans Gap [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
E1 Arrayan, Panhandle 1, Panhandle 2 and Logans Gap [Member]
Business Acquisition [Line Items]
Pro forma total revenue	$268,116	$201,573
Pro forma total expenses	326,990	192,762
Pro forma net (loss) income	-58,874	8,811
Less: pro forma net loss attributable to noncontrolling interest	-8,662	-7,176
Pro forma net (loss) income attributable to controlling interest	($50,212)	$15,987

Acquisitions_Schedule_of_Amoun

Acquisitions - Schedule of Amounts Included in Consolidated Statements of Operations (Detail) (USD $)	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Total revenue	$79,418,000	$71,519,000	$65,007,000	$49,549,000	$41,767,000	$57,257,000	$58,712,000	$43,837,000			$265,493,000	$201,573,000	$114,528,000
Total expenses											28,320,000	12,988,000	11,636,000
Net loss	-15,986,000	-9,281,000	7,167,000	-21,899,000	-19,376,000	4,244,000	43,988,000	-18,784,000			-39,999,000	10,072,000	-13,376,000
Less: net loss attributable to noncontrolling interest	4,406,000	-2,073,000	-4,032,000	-7,010,000	-6,197,000	3,248,000	-359,000	-3,579,000			-8,709,000	-6,887,000	-7,089,000
Net loss attributable to controlling interest	-20,392,000	-7,208,000	11,199,000	-14,889,000	-13,179,000	996,000	44,347,000	-15,205,000	-3,690,000	-10,898,000	-31,290,000	16,959,000	-6,287,000
E1 Arrayan, Panhandle 1, Panhandle 2 and Logans Gap [Member]
Business Acquisition [Line Items]
Total revenue											30,841,000
Total expenses											41,232,000
Net loss											-10,391,000
Less: net loss attributable to noncontrolling interest											-6,673,000
Net loss attributable to controlling interest											($3,718,000)

Recovered_Sheet1

Prepaid Expenses and Other Current Assets - Components of Prepaid Expenses and Other Current Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$15,275	$10,132
Prepaid construction costs	5,155
Sales tax	786	50
Other current assets:
Deposit for letters of credit	3,425
Deferred equity issuance costs	2,331
Other	982	1,233
Prepaid expenses and other current assets	$27,954	$11,415

Property_Plant_and_Equipment_S

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Subtotal	$2,629,147	$1,655,920
Less: accumulated depreciation	-278,291	-179,778
Property, plant and equipment, net	2,350,856	1,476,142
Operating wind farms [Member]
Property, Plant and Equipment [Line Items]
Subtotal	2,624,640	1,652,119
Furniture, fixtures and equipment [Member]
Property, Plant and Equipment [Line Items]
Subtotal	4,366	3,785
Land [Member]
Property, Plant and Equipment [Line Items]
Subtotal	$141	$16

Property_Plant_and_Equipment_A

Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation expense related to property, plant and equipment	$102.90	$82	$48.30
Decrease in depreciation expense	12.7	13	1.5
Ocotillo [Member]
Property, Plant and Equipment [Line Items]
Cash grant received				115.9
Pattern Santa Isabel LLC [Member]
Property, Plant and Equipment [Line Items]
Cash grant received				57.6
Spring Valley [Member]
Property, Plant and Equipment [Line Items]
Cash grant received					$79.90

Unconsolidated_Investments_Sch

Unconsolidated Investments - Schedule of Projects Accounted under Equity Method of Accounting (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Jun. 25, 2014
In Thousands, unless otherwise specified
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	$29,079	$107,055
South Kent [Member]
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	17,360	59,488
Percentage of ownership	50.00%	50.00%
Grand [Member]
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	11,719	26,464
Percentage of ownership	45.00%	45.00%
E1 Arrayan [Member]
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments		$21,103
Percentage of ownership		31.50%	70.00%

Unconsolidated_Investments_Add

Unconsolidated Investments - Additional Information (Detail)	Jun. 25, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 20, 2013	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 20, 2013
In Millions, unless otherwise specified	E1 Arrayan [Member]	E1 Arrayan [Member]	South Kent [Member]	South Kent [Member]	Grand [Member]	Grand [Member]	Grand [Member]	Grand [Member]	Grand [Member]
					USD ($)	USD ($)	CAD
Schedule of Equity Method Investments [Line Items]
PPA of project			20 years			20 years	20 years
Business acquisition, percentage of equity interest									45.00%
Business acquisition price					$79.50
Business acquisition, contingent payment based on exchange rate						$4.30	5
Percentage of ownership	70.00%	31.50%	50.00%	50.00%		45.00%	45.00%	45.00%

Unconsolidated_Investments_Sum

Unconsolidated Investments - Summary of Aggregated Balance Sheets and Operating Results (Detail) (E1 Arrayan [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
E1 Arrayan [Member]
Schedule of Equity Method Investments [Line Items]
Current assets		$16,362
Non-current assets		260,187
Total assets		276,549
Current liabilities		9,224
Non-current liabilities		197,597
Total liabilities		206,821
Total equity		69,728
Total liabilities and equity		276,549
Revenue	1,821
Other (income) expense	3,083	941	384
Net loss	($1,262)	($941)	($384)

Recovered_Sheet2

Accounts Payable and Other Accrued Liabilities - Components of Accounts Payable and Other Accrued Liabilities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Payables and Accruals [Abstract]
Accounts payable	$673	$168
Other accrued liabilities	9,202	6,329
Warranty settlement payments	639	2,187
LTSA upgrades liability	680
Land lease rent payable	2,115	953
Payroll liabilities	4,453	2,162
Property tax payable	4,625	3,490
Sales tax payable	2,406	261
Accounts payable and other accrued liabilities	$24,793	$15,550

Long_Term_Debt_Schedule_of_Lon

Long Term Debt - Schedule of Long Term Debt (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long term debt	$1,450,613	$1,249,218
Less: current portion	-121,561	-48,851
Long term debt, noncurrent	1,329,052	1,200,367
Hatchet Ridge [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Imputed
Long term debt	228,288	239,865
Long term debt, Interest Rate	1.43%	1.43%
Long term debt, Maturity	Dec-32
Gulf Wind [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Variable
Long term debt	156,122	166,448
Long term debt, Interest Rate	3.23%	3.25%
Long term debt, Maturity	Mar-20
St. Joseph [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Fixed
Long term debt	189,472	215,330
Long term debt, Interest Rate	5.88%	5.88%
Long term debt, Maturity	May-31
Spring Valley [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Variable
Long term debt	167,261	173,110
Long term debt, Interest Rate	2.62%	2.63%
Long term debt, Maturity	Jun-30
Santa Isabel [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Fixed
Long term debt	112,609	115,721
Long term debt, Interest Rate	4.57%	4.57%
Long term debt, Maturity	Sep-33
E1 Arrayan commercial [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Variable
Long term debt	99,665
Long term debt, Interest Rate	2.92%
Long term debt, Maturity	Mar-29
E1 Arrayan EKF [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Fixed
Long term debt	109,630
Long term debt, Interest Rate	5.56%
Long term debt, Maturity	Mar-29
Ocotillo commercial [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Variable
Long term debt	222,175	230,944
Long term debt, Interest Rate	1.98%	3.00%
Long term debt, Maturity	Aug-20
Ocotillo development [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Variable
Long term debt	106,700	107,800
Long term debt, Interest Rate	2.33%	2.35%
Long term debt, Maturity	Aug-33
Logan's Gap [Member]
Debt Instrument [Line Items]
Long term debt, Interest Type	Variable
Long term debt	$58,691
Long term debt, Interest Rate	1.64%
Long term debt, Maturity	Dec-15

Long_Term_Debt_Summary_of_Prin

Long Term Debt - Summary of Principal Payments Due under Long Term Debt (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Debt Disclosure [Abstract]
2015	$121,561
2016	65,877
2017	67,277
2018	72,750
2019	83,613
Thereafter	1,039,535
Long term debt	$1,450,613	$1,249,218

Long_Term_Debt_Schedule_of_Com

Long Term Debt - Schedule of Commitment Fees Incurred and Interest Expense Recorded (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
Interest and commitment fees incurred	$59,864	$57,478	$43,496
Capitalized interest, commitment fees, and letter of credit fees	-2,856	-4,210	-10,259
Letter of credit fees	4,377	3,530	720
Amortization of financing costs	6,309	6,816	2,546
Interest expense	$67,694	$63,614	$36,502

Long_Term_Debt_Additional_Info

Long Term Debt - Additional Information (Detail)

12 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

31-May-12

Nov. 15, 2012

Mar. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Nov. 15, 2012

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2013

Mar. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Mar. 31, 2010

Dec. 31, 2014

Dec. 31, 2013

Aug. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Oct. 31, 2011

Oct. 31, 2014

Oct. 31, 2012

Sep. 20, 2013

Oct. 31, 2012

Sep. 20, 2013

Oct. 31, 2012

Sep. 20, 2013

Oct. 31, 2012

Dec. 31, 2014

31-May-12

31-May-12

Dec. 31, 2014

31-May-12

31-May-12

Dec. 31, 2014

31-May-12

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

USD ($)

USD ($)

Eurodollar [Member]

Eurodollar [Member]

London Interbank Offered Rate (LIBOR) [Member]

London Interbank Offered Rate (LIBOR) [Member]

E1 Arrayan [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Development bank loan [Member]

Commercial bank loan [Member]

Hatchet Ridge [Member]

Hatchet Ridge [Member]

Gulf Wind [Member]

Gulf Wind [Member]

Gulf Wind [Member]

St. Joseph [Member]

St. Joseph [Member]

St. Joseph [Member]

Spring Valley [Member]

Spring Valley [Member]

Spring Valley [Member]

Santa Isabel [Member]

Santa Isabel [Member]

Santa Isabel [Member]

Ocotillo [Member]

Ocotillo [Member]

Ocotillo [Member]

Ocotillo [Member]

Ocotillo [Member]

Ocotillo [Member]

Ocotillo [Member]

Ocotillo [Member]

Commercial Tranche [Member]

Commercial Tranche [Member]

Commercial Tranche [Member]

EKF Tranche [Member]

EKF Tranche [Member]

Letter of Credit Facility [Member]

Corpbanca [Member]

Corpbanca [Member]

Logan's Gap [Member]

Logan's Gap [Member]

Logan's Gap [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

CAD

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Interest rate swaps [Member]

Revolving Credit Facility [Member]

Development bank loan [Member]

Development bank loan [Member]

Commercial bank loan [Member]

Commercial bank loan [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

Interest rate swaps [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

USD ($)

Revolving Credit Facility [Member]

Commercial bank loan [Member]

SecurityLoan

Letter of Credit Facility [Member]

USD ($)

USD ($)

USD ($)

E1 Arrayan [Member]

USD ($)

USD ($)

USD ($)

USD ($)

SecurityLoan

Letter of Credit Facility [Member]

Revolving Credit Facility [Member]

USD ($)

USD ($)

Letter of Credit Facility [Member]

USD ($)

Line of Credit Facility [Line Items]

Credit facility maturity period

4 years

22 years

10 years

20 years

20 years

7 years

Credit facility amount outstanding

$195,400,000

Construction loan facility

250,000,000

178,900,000

119,000,000

351,500,000

110,000,000

241,500,000

247,100,000

Bridge loan facility

53,300,000

57,500,000

56,600,000

Debt maturity period

30-Sep-33

31-Dec-15

Loan facility

1,450,613,000

1,249,218,000

228,288,000

239,865,000

156,122,000

166,448,000

189,472,000

215,330,000

167,261,000

173,110,000

112,609,000

115,721,000

467,300,000

58,691,000

Number of construction loan

2

1,000,000

Revolving credit facility outstanding amount

50,000,000

0

59,200,000

2,000,000

Percentage of loan in interest rate swaps

90.00%

95.80%

Prepaid bank loan

2,200,000

5,300,000

Debt interest rate decrease

1.00%

Line of credit facility

225,000,000

145,000,000

350,000,000

120,000,000

20,000,000

282,800,000

35,700,000

15,000,000

Borrowings

100,000,000

110,000,000

15,000,000

Description of base rate

The base rate loans accrue interest at the fluctuating rate per annum equal to the greatest of the (i) the prime rate, (ii) the federal funds rate plus 0.50% and (iii) the Eurodollar rate that would be in effect for a Eurodollar rate loan with an interest period of one month plus 1.0%, plus an applicable margin ranging from 1.25% to 1.75%. The Eurodollar rate loans accrue interest at a rate per annum equal to LIBOR, plus an applicable margin ranging from 2.25% to 2.75%.

The commercial tranche loan is a LIBOR loan and accrues interest at LIBOR plus 2.75% per annum from the closing until the sixth anniversary of closing, 3.00% from the sixth anniversary to the tenth anniversary of closing, 3.25% from the tenth anniversary to the fourteenth anniversary of closing, and 3.50% after the fourteenth anniversary of closing.

The EKF Tranche term loan accrues interest at a fixed rate of 5.56%, in each case, plus a margin of 0.25% from the sixth anniversary to the tenth anniversary of the closing, 0.50% from the tenth anniversary to the fourteenth anniversary of closing, and 0.75% after the fourteenth anniversary of closing.

Chilean Interbank Rate plus 1.00%

Termination year

Nov-15

Debt maturity period extended

31-Mar-16

Line of credit facility increased

35,000,000

Increase of additional borrowings

25,000,000

Letters of credit issued

45,100,000

44,800,000

Revolving credit facility amount drawn

$50,000,000

$56,000,000

$50,000,000

$56,000,000

Revolving commitment fee, percentage

0.50%

Debt instrument, margin range

1.25%

1.75%

2.25%

2.75%

Asset_Retirement_Obligations_A

Asset Retirement Obligations - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation [Abstract]
Estimated asset retirement period	20 years
Asset retirement obligations, description	The Company's asset retirement obligations represent the estimated cost of decommissioning the turbines, removing above-ground installations and restoring the sites at a date that is 20 years from the commencement of commercial operation of the facility.

Asset_Retirement_Obligations_R

Asset Retirement Obligations - Reconciliation of Beginning and Ending Aggregate Carrying Amounts of Asset Retirement Obligations (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Asset Retirement Obligation Disclosure [Abstract]
Beginning asset retirement obligations	$20,834	$19,056	$10,342
Additions during the year	7,195	767	7,971
Foreign currency translation adjustment	-228	-172	59
Accretion expense	1,471	1,183	684
Ending asset retirement obligations	$29,272	$20,834	$19,056

Derivative_Instruments_Schedul

Derivative Instruments - Schedule of Undesignated Derivative Instruments Classified as Assets (Liabilities) (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative [Line Items]
Fair Market Value, Current Portion	($16,307)	($16,171)
Fair Market Value, Long-Term Portion	-17,467	-7,439
Fair Market Value, Current Portion	18,506	13,937
Fair Market Value, Long-Term Portion	49,369	82,167
Undesignated Derivative Instruments [Member]
Derivative [Line Items]
Fair Market Value, Current Portion	15,103	10,038	15,197
Fair Market Value, Long-Term Portion	48,844	69,455	59,964
Gain (loss) Recognized into Income	-15,546	4,329	-11,904
Undesignated Derivative Instruments [Member] | Interest rate swaps [Member] | Ocotillo [Member]
Derivative [Line Items]
Maturity Dates	30-Jun-30	30-Jun-30	30-Jun-30
Fair Market Value, Current Portion	-3,403	-3,899	-1,980
Fair Market Value, Long-Term Portion			-2,931
Quantity	6	6	6
Fair Market Value, Long-Term Portion	2,523	14,358
Gain (loss) Recognized into Income	-11,339	15,367	-4,909
Undesignated Derivative Instruments [Member] | Interest rate cap [Member] | Gulf Wind [Member]
Derivative [Line Items]
Maturity Dates	31-Dec-24	31-Dec-24	31-Dec-24
Quantity	1	1	1
Fair Market Value, Long-Term Portion	352	681	447
Gain (loss) Recognized into Income	-329	234	-44
Undesignated Derivative Instruments [Member] | Energy derivative [Member] | Gulf Wind [Member]
Derivative [Line Items]
Maturity Dates	30-Apr-19	30-Apr-19	30-Apr-19
Quantity	1	1	1
Fair Market Value, Current Portion	18,506	13,937	17,177
Fair Market Value, Long-Term Portion	45,969	54,416	62,448
Gain (loss) Recognized into Income	-3,878	-11,272	-6,951
Designated Derivative Instruments [Member]
Derivative [Line Items]
Fair Market Value, Current Portion	-12,904	-12,272	-11,482
Fair Market Value, Long-Term Portion	-16,942		-32,395
Gain (loss) Recognized in OCI	-19,670	36,875	-11,170
Fair Market Value, Long-Term Portion		5,273
Designated Derivative Instruments [Member] | Interest rate swaps [Member] | Ocotillo [Member]
Derivative [Line Items]
Quantity	6	6	6
Maturity Dates	30-Jun-33	30-Jun-33	30-Jun-33
Fair Market Value, Current Portion	-1,917	-2,105	-952
Fair Market Value, Long-Term Portion			-1,962
Gain (loss) Recognized in OCI	-8,912	10,434	-2,914
Fair Market Value, Long-Term Portion	525	9,625
Designated Derivative Instruments [Member] | Interest rate swaps [Member] | Gulf Wind [Member]
Derivative [Line Items]
Quantity	7	7	7
Maturity Dates	15-Mar-20	15-Mar-20	15-Mar-20
Fair Market Value, Current Portion	-4,719	-5,289	-5,558
Fair Market Value, Long-Term Portion	-6,915	-7,439	-16,568
Gain (loss) Recognized in OCI	1,094	9,398	-1,835
Designated Derivative Instruments [Member] | Interest rate swaps [Member] | E1 Arrayan [Member]
Derivative [Line Items]
Quantity	3
Maturity Dates	31-Mar-32
Fair Market Value, Current Portion	-1,822
Fair Market Value, Long-Term Portion	-3,338
Gain (loss) Recognized in OCI	-1,983
Designated Derivative Instruments [Member] | Interest rate swaps [Member] | Spring Valley [Member]
Derivative [Line Items]
Quantity	2	2	2
Maturity Dates	28-Jun-30	28-Jun-30	28-Jun-30
Fair Market Value, Current Portion	-4,446	-4,878	-4,972
Fair Market Value, Long-Term Portion	-7,214		-13,865
Gain (loss) Recognized in OCI	-9,869	17,043	-6,421
Fair Market Value, Long-Term Portion		$3,087

Derivative_Instruments_Additio

Derivative Instruments - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	31-May-12	Dec. 31, 2011	Oct. 31, 2012
Derivative [Line Items]
Unrealized (losses) gains	($11,668,000)	$15,601,000	($4,953,000)
Earnings from accumulated other comprehensive loss, tax	404,000	0	0
Interest rate swaps [Member] | Gulf Wind [Member]
Derivative [Line Items]
Fixed interest rate	6.60%	6.60%	6.60%
Recorded cash flow hedge ineffectiveness	0	0	0
Reclassification into earnings from accumulated other comprehensive (loss) income	5,500,000	5,700,000	5,700,000
Interest rate swaps [Member] | Ocotillo [Member]
Derivative [Line Items]
Recorded cash flow hedge ineffectiveness	0	0	0
Reclassification into earnings from accumulated other comprehensive (loss) income	2,200,000	1,100,000	0
Unrealized (losses) gains	-11,300,000	15,400,000	-4,900,000
Interest rate swaps [Member] | Ocotillo [Member] | Development bank term loans [Member]
Derivative [Line Items]
Fixed interest rate						2.50%
Interest rate swaps [Member] | Ocotillo [Member] | Commercial bank term loans [Member]
Derivative [Line Items]
Fixed interest rate						2.20%
Interest rate swaps [Member] | E1 Arrayan [Member]
Derivative [Line Items]
Reclassification into earnings from accumulated other comprehensive (loss) income	1,100,000	0	0
Earnings from accumulated other comprehensive loss, tax	400,000	0	0
Interest rate swaps [Member] | E1 Arrayan [Member] | First two years [Member]
Derivative [Line Items]
Fixed interest rate				3.40%
Debt interest rate increases by every four years				5.80%
Interest rate swaps [Member] | E1 Arrayan [Member] | Every fourth anniversary [Member]
Derivative [Line Items]
Debt interest rate increases by every four years				0.25%
Interest rate swaps [Member] | Spring Valley [Member]
Derivative [Line Items]
Fixed interest rate					5.50%
Recorded cash flow hedge ineffectiveness	0	0	0
Reclassification into earnings from accumulated other comprehensive (loss) income	5,000,000	5,100,000	0
Debt interest rate increases by every four years					0.25%
Interest rate swaps [Member] | Undesignated Derivative Instruments [Member] | Ocotillo [Member]
Derivative [Line Items]
Derivative maturity date	30-Jun-30	30-Jun-30	30-Jun-30
Interest rate swaps [Member] | Two through eight years [Member] | Gulf Wind [Member]
Derivative [Line Items]
Fixed interest rate	6.60%
Interest rate swaps [Member] | Year nine [Member] | Gulf Wind [Member]
Derivative [Line Items]
Fixed interest rate		7.10%
Interest rate swaps [Member] | Year ten [Member] | Gulf Wind [Member]
Derivative [Line Items]
Fixed interest rate			7.60%
Interest rate cap [Member] | Gulf Wind [Member]
Derivative [Line Items]
Derivative future rate	6.00%
Derivative effective date	31-Mar-20
Term of loan to be refinanced	10 years
Unrealized (losses) gains	-300,000	200,000	0
Derivative instrument, fair value	400,000	700,000	400,000
Interest rate cap [Member] | Undesignated Derivative Instruments [Member] | Gulf Wind [Member]
Derivative [Line Items]
Derivative maturity date	31-Dec-24	31-Dec-24	31-Dec-24
Notional amount reduced quarterly	42,100,000
Energy derivative [Member]
Derivative [Line Items]
Unrealized (losses) gains	-3,900,000	-11,300,000	-7,000,000
Energy derivative [Member] | Gulf Wind [Member]
Derivative [Line Items]
Unrealized (losses) gains	-3,900,000	-11,300,000	-7,000,000
Derivative instrument, fair value	$64,500,000	$68,400,000	$79,600,000
Fixed price of derivative instrument	58.00%
Energy derivative [Member] | Undesignated Derivative Instruments [Member] | Gulf Wind [Member]
Derivative [Line Items]
Derivative maturity date	30-Apr-19	30-Apr-19	30-Apr-19

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive (Loss) Income - Summary of Accumulated Other Comprehensive (Loss) Income (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), Beginning balance	($17,377)	($45,506)	($35,610)
Net current period other comprehensive income (loss)	-36,536	31,039	-9,896
Accumulated other comprehensive income (loss), Ending balance	-53,913	-17,377	-45,506
Grand [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Acquisition		-2,910
Foreign Currency [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), Beginning balance	-8,463	-154	-2,903
Net current period other comprehensive income (loss)	-10,875	-8,309	2,749
Accumulated other comprehensive income (loss), Ending balance	-19,338	-8,463	-154
Effective Portion of Change in Fair Value of Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), Beginning balance	-7,002	-43,877	-32,707
Net current period other comprehensive income (loss)	-19,670	36,875	-11,170
Accumulated other comprehensive income (loss), Ending balance	-26,672	-7,002	-43,877
Proportionate Share of Equity Investee's OCI [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), Beginning balance	-1,912	-1,475
Net current period other comprehensive income (loss)	-5,991	2,473	-1,475
Accumulated other comprehensive income (loss), Ending balance	-7,903	-1,912	-1,475
Proportionate Share of Equity Investee's OCI [Member] | Grand [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Acquisition		($2,910)

Fair_Value_Measurements_Financ

Fair Value Measurements - Financial Assets and (Liabilities) Required Fair Value Measurement on Recurring Basis (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	$34,101	$72,494
Interest rate swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	-30,726	3,460
Interest rate cap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	352	681
Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	64,475	68,353
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	-30,374	4,141
Level 2 [Member] | Interest rate swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	-30,726	3,460
Level 2 [Member] | Interest rate cap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	352	681
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	64,475	68,353
Level 3 [Member] | Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets and (liabilities)	$64,475	$68,353

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unrealized (losses) gains	($11,668)	$15,601	($4,953)
Energy derivative [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unrealized (losses) gains	($3,900)	($11,300)	($7,000)
Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value inputs, discount rate	7.00%
Fair value inputs, probability factor	75.00%

Fair_Value_Measurements_Reconc

Fair Value Measurements - Reconciliation of Contingent Liabilities and Energy Derivative Contract Measured at Fair Value (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance	$68,353	$71,624	$80,591
Settlements	-13,524	-8,797	-19,644
Change in fair value, net of settlements	9,646	5,526	10,677
Ending balance	64,475	68,353	71,624
Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance	68,353	79,625	86,577
Settlements	-13,524	-16,798	-19,644
Change in fair value, net of settlements	9,646	5,526	12,692
Ending balance	64,475	68,353	79,625
Contingent Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance		-8,001	-5,986
Settlements		8,001
Change in fair value, net of settlements			-2,015
Ending balance			($8,001)

Fair_Value_Measurements_Carryi

Fair Value Measurements - Carrying Amounts and Fair Values of Company's Financial Liabilities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current portion, As reflected on the balance sheet	$1,450,613	$1,249,218
Fair value, Long-term debt, including current portion	1,416,744	1,165,119
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value, Long-term debt, including current portion	$1,416,744	$1,165,119

Income_Taxes_Components_of_Pro

Income Taxes - Components of Provision for Income Taxes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$0	$0	$0
State	0	0	0
Foreign	182
Total current expense (benefit)	182
Deferred:
Federal		2,961
State	0	0	0
Foreign	2,954	1,585	-3,604
Total deferred expense (benefit)	2,954	4,546	-3,604
Total provision for income taxes	$3,136	$4,546	($3,604)

Income_Taxes_Domestic_and_Fore

Income Taxes - Domestic and Foreign Components of Net Income (Loss) Before Income Tax (Benefit) Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
U.S.	($34,788)	$4,022	($17,810)
Foreign	-2,075	10,596	830
Total	($36,863)	$14,618	($16,980)

Income_Taxes_Reconciliation_of

Income Taxes - Reconciliation of Statutory U.S.Federal Income Tax Rate to Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Computed tax at statutory rate	35.00%	35.00%	35.00%
Book/tax basis difference			27.20%
Partnership income not subject to taxes			-40.90%
Adjustment for income in non-taxable entities allocable to noncontrolling interest	-7.60%	16.50%
Foreign rate differential	0.00%	0.00%	0.00%
Tax rate differential on pre-tax book income, other	5.60%	2.10%
Local tax on branch profits/(losses)-Puerto Rico	1.60%	13.10%
Permanent book/tax differences (domestic only)	-0.10%	-2.20%
Valuation Allowance	-33.40%	187.20%
Deferred tax liability on Chilean shareholder liability due to tax regime change	-3.60%
Change in tax rate due to change in Chilean tax regime	-6.20%
Other	0.10%	3.10%
ARRA Section 1603 grant-basis reduction deferred tax assets		-223.70%
Effective income tax rate	-8.60%	31.10%	21.30%

Income_Taxes_Components_of_Def

Income Taxes - Components of Deferred Tax Assets and Deferred Tax Liabilities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred tax assets/(liabilities)-current:
Accruals, prepaids and other current deferred tax assets and liabilities	($344)	$2,399
Basis difference in derivatives	4,779	2,835
Total gross deferred tax assets/(liabilities)	4,435	5,234
Less: valuation allowance	-4,266	-4,661
Total net deferred tax assets/(liabilities)-current	169	573
Deferred tax assets/(liabilities)-non-current:
Property, plant and equipment	-104,767	-36,548	-47,894
Basis difference in foreign subsidiaries	37,626	40,097
Partnership interest	994	-4,917
Lease Hatchet Ridge	28,044	29,314
Asset retirement obligation	5,216	4,649
Equity method		3,794
Unrealized loss on derivatives		-5,830
Other temp differences	256
Net operating loss carryforwards	130,248	61,441	45,302
Other non current deferred tax assets and liabilities	-5,081	-4,595	-690
Change in tax status			4,599
Accruals not currently deductible			443
Total gross deferred tax assets/(liabilities)-non-current	92,536	87,405	1,760
Less: valuation allowance	-107,480	-95,318	-482
Total net deferred tax assets/(liabilities)-non-current	-14,944	-7,913	1,278
Total net deferred tax assets/(liabilities)	($14,775)	($7,340)	$1,278

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Net change in valuation allowance	$11,800,000	$99,500,000
Limitation on set off of net operating loss	Internal Revenue Code Section 382 places a limitation ( the "Section 382 Limitation") on the amount of taxable income that can be offset by net operating loss ("NOL") and credit carryforwards, as well as built-in loss items, after a change in control (generally greater than 50% change in ownership) of a loss corporation.
Unrecognized tax benefits	0
Significant change in unrecognized tax benefits is reasonably possible, amount	0
Interest expense or penalties associated with unrecognized tax benefits	0	0	0
Undistributed earnings of foreign subsidiary	7,600,000
Special tax rate related to tax holiday	4.00%
Income tax holiday, termination date	For a 15 year period and is scheduled to terminate on December 31, 2026.
Tax holiday impact, decrease in foreign deferred tax expense	2,100,000
Class A Common Stock [Member]
Income Taxes [Line Items]
Tax holiday impact on net income per share of basic and diluted	$0.05
Class B Common Stock [Member]
Income Taxes [Line Items]
Tax holiday impact on net income per share of basic and diluted	$0.14
Domestic [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	225,600,000
Net operating loss carryforwards, beginning expiry year	2032
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$25,500,000
Net operating loss carryforwards, beginning expiry year	2032

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	12 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Changes In Equity And Comprehensive Income Line Items [Line Items]
Common stock conversion basis	All of the outstanding Class B common stock automatically convert, on a one-for-one basis, into Class A shares. There are no other conversion rights attached to Class B common stock.
Common stock voting rights	Holders of the Companybs Class A common stock and Class B common stock are entitled to one vote per share on all matters submitted to a vote of stockholders and will vote as a single class under all circumstances, unless otherwise required by law. Shares held by Pattern Development are entitled to certain approval rights if Pattern Development beneficially owns not less than thirty-three and one-third percent of the Companybs outstanding common stock, pursuant to the Shareholder Approval Rights Agreement between the Company and Pattern Development dated October 2, 2013.
Preferred stock, authorized	100,000,000	100,000,000
Preferred stock, issued	0	0	0
Preferred stock, outstanding	0	0	0
Class B Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Common stock conversion basis	One-to-one basis
Class A Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Dividends payable, amount per share	0.335	$0.34
Common stock dividends per share annualized basis	1.34
Dividend declared date		29-Oct-14
Dividend payable date	30-Jan-15
Dividend payment, date of stockholders record	31-Dec-14

Stockholders_Equity_Summary_of

Stockholders' Equity - Summary of Noncontrolling Interest Balances (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Jun. 25, 2014
In Thousands, unless otherwise specified
Noncontrolling Interest [Line Items]
Noncontrolling interest	$530,586	$99,794
E1 Arrayan [Member]
Noncontrolling Interest [Line Items]
Percentage of ownership		31.50%	70.00%
Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest	530,586	99,794
Noncontrolling Interest [Member] | Gulf Wind [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest	97,061	99,794
Percentage of ownership	60.00%	60.00%
Noncontrolling Interest [Member] | E1 Arrayan [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest	35,624
Percentage of ownership	30.00%
Noncontrolling Interest [Member] | Panhandle 1 [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest	205,333
Percentage of ownership	21.00%
Noncontrolling Interest [Member] | Panhandle 2 [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interest	$192,568
Percentage of ownership	19.00%

Equity_Incentive_Award_Plan_Ad

Equity Incentive Award Plan - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$4,105,000	$511,000
Performance based restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	600,000
Restricted stock awards vested	27,717
Restricted stock awards vested, weighted average grant date fair value	$27.03
Restricted stock awards unvested	0
2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of stock options exercised	100,000	0
Cash received from employee stock option exercises	300,000	0
2013 Plan [Member] | Class A Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares available for issuance	2,292,642
2013 Plan [Member] | Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs granted	178,089
Stock-based compensation expense	4,100,000	500,000
Unrecorded stock-based compensation expense	3,100,000
Weighted-average period for amortization	1 year 9 months 18 days
Fair value of restricted stock awards released	2,900,000	200,000
Weighted average grant date fair value	$27.54	$24.15
Restricted stock awards vested	81,914
Restricted stock awards vested, weighted average grant date fair value	$26.64
Restricted stock awards unvested	145,732	76,262
2013 Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be issued under plan			3,000,000
Aggregate intrinsic value of stock options exercised	108,191
Unrecorded stock-based compensation expense	$1,100,000
Weighted-average period for amortization	1 year 9 months 18 days
2013 Plan [Member] | Employee [Member] | Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs granted	161,757
2013 Plan [Member] | Director [Member] | Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs granted	16,332

Equity_Incentive_Award_Plan_Sc

Equity Incentive Award Plan - Schedule of Weighted Average Assumptions (Detail) (Stock options [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.68%	1.68%
Expected life (in years)	5 years 9 months 18 days	5 years 9 months 18 days
Expected volatility	36.00%	36.00%
Expected dividend yield	5.70%	5.70%

Equity_Incentive_Award_Plan_Su

Equity Incentive Award Plan - Summary of Stock Option Activity (Detail) (2013 Plan [Member], USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate Intrinsic Value, Exercised	$100,000	$0
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options Outstanding, Beginning balance	444,823
Number of Options Outstanding, Exercised	-14,861
Number of Options Outstanding, Ending balance	429,962
Number of Options Outstanding, Exercisable at December 31, 2014	170,434
Number of Options Outstanding, Vested and expected to vest as of December 31, 2014	429,962
Weighted Average Exercise Price, Beginning balance	$22
Weighted Average Exercise Price, Exercised	$22
Weighted Average Exercise Price, Ending balance	$22
Weighted Average Exercise Price, Exercisable at December 31, 2014	$22
Weighted Average Exercise Price, Vested and expected to vest as of December 31, 2014	$22
Weighted Average Remaining Contractual Life (in years), Ending balance	8 years 9 months 18 days
Weighted Average Remaining Contractual Life (in years), Exercisable at December 31, 2014	8 years 9 months 18 days
Weighted Average Remaining Contractual Life (in years), Vested and expected to vest as of December 31, 2014	8 years 9 months 18 days
Aggregate Intrinsic Value, Exercised	108,191
Aggregate Intrinsic Value, Ending balance	1,143,699
Aggregate Intrinsic Value, Exercisable at December 31, 2014	453,354
Aggregate Intrinsic Value, Vested and expected to vest as of December 31, 2014	$1,143,699

Equity_Incentive_Award_Plan_Su1

Equity Incentive Award Plan - Summary of Restricted Stock Awards Activity (Detail) (Restricted stock awards [Member], 2013 Plan [Member], USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Restricted stock awards [Member] | 2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs Outstanding, Beginning balance	76,262
Number of RSAs Outstanding, Granted	178,089
Number of RSAs Outstanding, Released	-81,914
Number of RSAs Outstanding, Forfeited	-2,174
Number of RSAs Outstanding, Repurchased for employee tax withholding	-24,531
Number of RSAs Outstanding, Ending balance	145,732	76,262
Weighted Average Grant Date Fair Value, Beginning balance	$22.53
Weighted Average Grant Date Fair Value, Granted	$27.54	$24.15
Weighted Average Grant Date Fair Value, Released	$26.64
Weighted Average Grant Date Fair Value, Forfeited	$27.03
Weighted Average Grant Date Fair Value, Repurchased for employee tax withholding	$26.44
Weighted Average Grant Date Fair Value, Ending balance	$25.62	$22.53
Aggregate Intrinsic Value, Ending balance	$3,593,751

Earnings_Per_Share_Computation

Earnings Per Share - Computations of Basic and Diluted Earnings (Loss) per Share (Detail) (USD $)	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator for basic and diluted earnings (loss) per share:
Net loss attributable to controlling interest	($20,392)	($7,208)	$11,199	($14,889)	($13,179)	$996	$44,347	($15,205)	($3,690)	($10,898)	($31,290)	$16,959	($6,287)
Less: dividends declared											-56,976	-11,103
Less: deemed dividends											-21,901
Net loss attributable to common stockholders		-29,688	-11,239	-26,068					-37,285	-66,972	-110,167	-24,439
Weighted average number of shares:
Class A common stock-basic			41,174,697						38,331,595
Stock options [Member]
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252	52,915	14,462
Less: antidilutive securities
Antidilutive securities		-133,197								-112,252	-52,915	-14,462
Restricted stock awards [Member]
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451	27,401	38,131
Less: antidilutive securities
Antidilutive securities		-191,451								-191,451	-27,401	-38,131
Class A Common Stock [Member]
Numerator for basic and diluted earnings (loss) per share:
Less: dividends declared		-15,258	-14,981	-11,179					-26,138	-41,395
Weighted average number of shares:
Class A common stock-basic		46,317,932		35,533,166						41,022,962	42,361,959	35,448,056
Add dilutive effect of:
Class A common stock-fully diluted		62,197,580	57,065,219	51,421,931					54,214,953	56,881,665	57,997,275	51,055,649
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		46,317,932	57,065,219	51,421,931					54,214,953	56,577,962	42,361,959	35,448,056
Class B common stock-basic and diluted											42,361,959	35,448,056
Calculation of basic and diluted earnings (loss) per share:
Dividends		$0.33	$0.36	$0.31					$0.68	$1.01	$1.34	$0.31
Undistributed loss		($0.48)	($0.20)	($0.51)					($0.69)	($1.18)	($1.90)	($0.48)
Basic loss per share	($0.36)	($0.15)	$0.17	($0.20)					($0.01)	($0.17)	($0.56)	($0.17)
Basic and diluted loss per share					($0.17)						($0.56)	($0.17)
Diluted loss per share	($0.36)	($0.15)	$0.16	($0.29)					($0.07)	($0.19)	($0.56)	($0.17)
Cash dividends declared per Class A common share	$0.34	$0.33	$0.32	$0.31					$0.63	$0.96	$1.30	$0.31
Class B Common Stock [Member]
Numerator for basic and diluted earnings (loss) per share:
Less: deemed dividends		$7,222	$7,457						$7,457	$14,679	$21,901
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000	15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000									-15,555,000	-15,555,000
Class B common stock-basic and diluted		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000	15,555,000	15,555,000
Calculation of basic and diluted earnings (loss) per share:
Deemed dividends	$0.46	$0.46	$0.48						$0.48	$0.94	$1.41
Undistributed loss		($0.48)	($0.20)						($0.69)	($1.18)	($1.90)	($0.48)
Basic and diluted loss per share	($0.23)	($0.02)	$0.28	($0.51)	($0.48)				($0.21)	($0.24)	($0.49)	($0.48)
Deemed dividends per Class B common share	$0.46	$0.46	$0.48						$0.48	$0.94	$1.41

Geographic_Information_Summary

Geographic Information - Summary of Geographical Revenues and Assets (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$79,418	$71,519	$65,007	$49,549	$41,767	$57,257	$58,712	$43,837	$265,493	$201,573	$114,528
Property, Plant and Equipment, net	2,350,856				1,476,142				2,350,856	1,476,142
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									201,408	161,505	73,089
Property, Plant and Equipment, net	1,784,219				1,210,319				1,784,219	1,210,319
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									46,593	40,068	41,439
Property, Plant and Equipment, net	233,690				265,823				233,690	265,823
Chile [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									17,492
Property, Plant and Equipment, net	$332,947								$332,947

Commitments_Contingencies_and_2

Commitments, Contingencies and Warranties - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Commitments [Line Items]
Operating leases, Rent expense	$8.80	$6.10	$4.20
Purchase commitments, outstanding	16.7
Warranty settlements for liquidated damage payments		21.9
Blade manufacturer [Member]
Other Commitments [Line Items]
Warranty settlements		24.1
Maximum [Member]
Other Commitments [Line Items]
Future refund of liquidated damage	0.6	2.2
Pattern Santa Isabel LLC [Member]
Other Commitments [Line Items]
Tax indemnification liability	7.2
Construction-related open commitments [Member]
Other Commitments [Line Items]
Purchase commitments, outstanding	171
Wind Turbine [Member]
Other Commitments [Line Items]
Purchase commitments, outstanding	6.3
Additional contingency liability	4
Service and Maintenance Agreements [Member]
Other Commitments [Line Items]
Term of agreement	12 years
Purchase commitments, outstanding	353.4
Wind Farm [Member]
Other Commitments [Line Items]
Term of agreement	20 years
Purchase commitments, outstanding	6.7
Power purchase agreements [Member]
Other Commitments [Line Items]
Irrevocable letters of credit	57.2
Power purchase agreements [Member] | Minimum [Member]
Other Commitments [Line Items]
Power purchase agreements termination period	2025
Power purchase agreements [Member] | Maximum [Member]
Other Commitments [Line Items]
Power purchase agreements termination period	2039
Project Finance Agreements [Member]
Other Commitments [Line Items]
Irrevocable letters of credit	107.1
Project Finance Agreements [Member] | Revolving Credit Facility [Member]
Other Commitments [Line Items]
Irrevocable letters of credit	45.1
Service Providers [Member]
Other Commitments [Line Items]
Bonuses payable	0.2
Turbine manufacturers [Member]
Other Commitments [Line Items]
Bonuses payable	$0	$0

Commitments_Contingencies_and_3

Commitments, Contingencies and Warranties - Schedule of Future Minimum Payments Related to Land Leases (Detail) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$5,971
2016	5,406
2017	5,412
2018	5,418
2019	5,425
Thereafter	141,443
Total	$169,075

Commitments_Contingencies_and_4

Commitments, Contingencies and Warranties - Schedule of Operations and Maintenance Commitments (Detail) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$40,118
2016	44,583
2017	44,387
2018	38,746
2019	36,707
Thereafter	148,872
Total	$353,413

Related_Party_Transactions_Add

Related Party Transactions - Additional Information (Detail)

12 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 19, 2014

Jun. 25, 2014

Dec. 31, 2014

Jun. 25, 2014

Jun. 25, 2014

Jun. 30, 2014

Dec. 31, 2014

Dec. 31, 2014

Sep. 05, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 19, 2014

Dec. 31, 2014

Dec. 19, 2014

Jun. 30, 2014

Jun. 25, 2014

Dec. 31, 2014

Jun. 30, 2014

Jun. 25, 2014

Jun. 30, 2014

Jun. 25, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 20, 2013

Nov. 10, 2014

Dec. 31, 2014

Nov. 10, 2014

Nov. 10, 2014

USD ($)

USD ($)

USD ($)

Logan's Gap [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

E1 Arrayan [Member]

Panhandle 1 [Member]

Indirect Guarantee of Indebtedness [Member]

Guarantee Obligation by PEG LP [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Pattern Development [Member]

Grand [Member]

Grand [Member]

Grand [Member]

Panhandle 2 [Member]

Panhandle 2 [Member]

Panhandle 2 [Member]

Panhandle 2 [Member]

USD ($)

USD ($)

Majority control [Member]

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Logan's Gap [Member]

Logan's Gap [Member]

Logan's Gap [Member]

Panhandle 1 [Member]

Panhandle 1 [Member]

Panhandle 1 [Member]

Panhandle 1 [Member]

Panhandle 1 [Member]

Class B Membership Interests [Member]

Class B Membership Interests [Member]

USD ($)

CAD

Panhandle 1 [Member]

Panhandle 1 [Member]

Panhandle 1 [Member]

Class B Membership Interests [Member]

MW

MW

USD ($)

USD ($)

MW

MW

USD ($)

USD ($)

Panhandle 1 [Member]

Panhandle 1 [Member]

USD ($)

USD ($)

Panhandle 1 [Member]

MW

Related Party Transaction [Line Items]

Percentage of service fee of direct costs

5.00%

Amounts payable for services and supplies

$800,000

$1,200,000

Related party receivable

700,000

200,000

100,000

0

Letters-of-credit outstanding

0

0

Guarantee for payment obligations

14,000,000

20,000,000

Remaining credit facility

6,000,000

Business acquisition, percentage of equity interest

38.50%

70.00%

100.00%

45.00%

Business acquisition, contingent payment

4,000,000

4,300,000

5,000,000

Acquired percentage of issued and outstanding of common stock

100.00%

Effective date of acquisition

25-Jun-14

19-Dec-14

30-Jun-14

10-Nov-14

Indirect interest

31.50%

Completed construction of wind power project

115

Total purchase price

15,099,000

45,300,000

334,650,000

Additional ownership interest acquired, percentage

38.50%

Ownership interest

100.00%

79.00%

79.00%

100.00%

100.00%

81.00%

100.00%

Business acquisition acquired entity purchase price

15,100,000

124,400,000

124,400,000

123,800,000

Capacity agreed to acquire

172

147

Power generation capacity

164

218

218

182

Amount paid for acquiring trade name

1

Repayments of acquired debt

195,400,000

Related party payable

5,003,000

44,000

5,000,000

Management fees

3,317,000

911,000

Employer contribution, percentage

5.00%

Employer contribution, amount

$300,000

$100,000

$0

Related_Party_Transactions_All

Related Party Transactions - Allocated Costs Included in Combined Statement of Operations (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Related Party Transactions [Abstract]
Project expense		$1,995	$1,998
Related party general and administrative	5,787	8,169	10,604
Related party income	-2,612	-665
Other income, net		-551	-210
Total	$3,175	$8,948	$12,392

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data - Summary of Quarterly Consolidated Statements of Operations (Detail) (USD $)	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Quarterly Financial Information [Line Items]
Revenue	$79,418	$71,519	$65,007	$49,549	$41,767	$57,257	$58,712	$43,837			$265,493	$201,573	$114,528
Gross profit (loss)	26,311	17,669	27,023	12,298	4,729	21,471	26,222	8,294			83,301	60,716	30,658
Net (loss) income	-15,986	-9,281	7,167	-21,899	-19,376	4,244	43,988	-18,784			-39,999	10,072	-13,376
Net (loss) income attributable to noncontrolling interest	4,406	-2,073	-4,032	-7,010	-6,197	3,248	-359	-3,579			-8,709	-6,887	-7,089
Net (loss) income attributable to controlling interest	($20,392)	($7,208)	$11,199	($14,889)	($13,179)	$996	$44,347	($15,205)	($3,690)	($10,898)	($31,290)	$16,959	($6,287)
Class A Common Stock [Member]
Schedule Of Quarterly Financial Information [Line Items]
Basic (loss) earnings per share	($0.36)	($0.15)	$0.17	($0.20)					($0.01)	($0.17)	($0.56)	($0.17)
Diluted (loss) earnings per share	($0.36)	($0.15)	$0.16	($0.29)					($0.07)	($0.19)	($0.56)	($0.17)
Basic and diluted earnings (loss) per share					($0.17)						($0.56)	($0.17)
Cash dividends declared per share	$0.34	$0.33	$0.32	$0.31					$0.63	$0.96	$1.30	$0.31
Class B Common Stock [Member]
Schedule Of Quarterly Financial Information [Line Items]
Basic and diluted earnings (loss) per share	($0.23)	($0.02)	$0.28	($0.51)	($0.48)				($0.21)	($0.24)	($0.49)	($0.48)
Deemed dividends	$0.46	$0.46	$0.48						$0.48	$0.94	$1.41

Selected_Quarterly_Financial_D3

Selected Quarterly Financial Data - Computations of Basic and Diluted Earnings (Loss) per Share (Detail) (USD $)	3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator for basic and diluted earnings (loss) per share:
Net income (loss) attributable to controlling interest	($20,392)	($7,208)	$11,199	($14,889)	($13,179)	$996	$44,347	($15,205)	($3,690)	($10,898)	($31,290)	$16,959	($6,287)
Dividends declared on Class A common stock											-56,976	-11,103
Less: deemed dividends on Class B common shares											21,901
Net loss attributable to common stockholders		-29,688	-11,239	-26,068					-37,285	-66,972	-110,167	-24,439
Weighted average number of shares:
Class A common stock-basic			41,174,697						38,331,595
Weighted average number of shares:
Class A common stock-basic			41,174,697						38,331,595
Stock options [Member]
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252	52,915	14,462
Less: antidilutive securities
Antidilutive securities		-133,197								-112,252	-52,915	-14,462
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252	52,915	14,462
Less: antidilutive securities
Antidilutive securities		-133,197								-112,252	-52,915	-14,462
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252	52,915	14,462
Less: antidilutive securities
Antidilutive securities		-133,197								-112,252	-52,915	-14,462
Restricted stock awards [Member]
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451	27,401	38,131
Less: antidilutive securities
Antidilutive securities		-191,451								-191,451	-27,401	-38,131
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451	27,401	38,131
Less: antidilutive securities
Antidilutive securities		-191,451								-191,451	-27,401	-38,131
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451	27,401	38,131
Less: antidilutive securities
Antidilutive securities		-191,451								-191,451	-27,401	-38,131
As Previously Reported [Member]
Numerator for basic and diluted earnings (loss) per share:
Net income (loss) attributable to controlling interest		-7,208	11,199	-14,889					-3,690	-10,898
Net loss attributable to common stockholders		-29,688	-3,782	-26,068					-29,828	-66,972
Weighted average number of shares:
Class A common stock-basic			41,174,697						38,331,595
Weighted average number of shares:
Class A common stock-basic			41,174,697						38,331,595
As Previously Reported [Member] | Stock options [Member]
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252
Less: antidilutive securities
Antidilutive securities		-133,197		-95,219						-112,252
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252
Less: antidilutive securities
Antidilutive securities		-133,197		-95,219						-112,252
Add dilutive effect of:
Dilutive effect		133,197	107,979	95,219					100,814	112,252
Less: antidilutive securities
Antidilutive securities		-133,197		-95,219						-112,252
As Previously Reported [Member] | Restricted stock awards [Member]
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451
Less: antidilutive securities
Antidilutive securities		-191,451		-238,546						-191,451
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451
Less: antidilutive securities
Antidilutive securities		-191,451		-238,546						-191,451
Add dilutive effect of:
Dilutive effect		191,451	227,543	238,546					227,543	191,451
Less: antidilutive securities
Antidilutive securities		-191,451		-238,546						-191,451
Class A Common Stock [Member]
Earnings Per Share [Line Items]
Diluted earnings (loss) per share	($0.36)	($0.15)	$0.16	($0.29)					($0.07)	($0.19)	($0.56)	($0.17)
Numerator for basic and diluted earnings (loss) per share:
Dividends declared on Class A common stock		-15,258	-14,981	-11,179					-26,138	-41,395
Cash dividends declared per Class A common share	$0.34	$0.33	$0.32	$0.31					$0.63	$0.96	$1.30	$0.31
Weighted average number of shares:
Class A common stock-basic		46,317,932		35,533,166						41,022,962	42,361,959	35,448,056
Add dilutive effect of:
Class A common stock-fully diluted		62,197,580	57,065,219	51,421,931					54,214,953	56,881,665	57,997,275	51,055,649
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		46,317,932	57,065,219	51,421,931					54,214,953	56,577,962	42,361,959	35,448,056
Add dilutive effect of:
Class A common stock-fully diluted		62,197,580	57,065,219	51,421,931					54,214,953	56,881,665	57,997,275	51,055,649
Class A common stock-fully diluted		62,197,580	57,065,219	51,421,931					54,214,953	56,881,665	57,997,275	51,055,649
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		46,317,932	57,065,219	51,421,931					54,214,953	56,577,962	42,361,959	35,448,056
Class B common stock-basic and diluted											42,361,959	35,448,056
Weighted average number of shares:
Class A common stock-basic		46,317,932		35,533,166						41,022,962	42,361,959	35,448,056
Add dilutive effect of:
Class A common stock-fully diluted		62,197,580	57,065,219	51,421,931					54,214,953	56,881,665	57,997,275	51,055,649
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		46,317,932	57,065,219	51,421,931					54,214,953	56,577,962	42,361,959	35,448,056
Calculation of basic and diluted earnings (loss) per share:
Dividends		$0.33	$0.36	$0.31					$0.68	$1.01	$1.34	$0.31
Undistributed loss		($0.48)	($0.20)	($0.51)					($0.69)	($1.18)	($1.90)	($0.48)
Basic earnings (loss) per share	($0.36)	($0.15)	$0.17	($0.20)					($0.01)	($0.17)	($0.56)	($0.17)
Undistributed loss		($0.48)	($0.20)	($0.51)					($0.69)	($1.18)	($1.90)	($0.48)
Basic and diluted earnings (loss) per share					($0.17)						($0.56)	($0.17)
Class A Common Stock [Member] | As Previously Reported [Member]
Earnings Per Share [Line Items]
Diluted earnings (loss) per share		($0.15)	$0.20	($0.20)					($0.07)	($0.20)
Numerator for basic and diluted earnings (loss) per share:
Dividends declared on Class A common stock		-15,258	-14,981	-11,179					-26,138	-41,395
Cash dividends declared per Class A common share		$0.33								$0.96
Weighted average number of shares:
Class A common stock-basic		40,980,989		35,533,166						38,342,998
Add dilutive effect of:
Class A common stock-fully diluted		56,860,637	57,065,219	51,421,931					54,214,953	54,201,701
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		40,980,989	57,065,219	35,533,166					54,214,953	53,897,998
Add dilutive effect of:
Class A common stock-fully diluted		56,860,637	57,065,219	51,421,931					54,214,953	54,201,701
Class A common stock-fully diluted		56,860,637	57,065,219	51,421,931					54,214,953	54,201,701
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		40,980,989	57,065,219	35,533,166					54,214,953	53,897,998
Weighted average number of shares:
Class A common stock-basic		40,980,989		35,533,166						38,342,998
Add dilutive effect of:
Class A common stock-fully diluted		56,860,637	57,065,219	51,421,931					54,214,953	54,201,701
Less: antidilutive securities
Class A common stock-diluted (excluding antidilutive securities)		40,980,989	57,065,219	35,533,166					54,214,953	53,897,998
Calculation of basic and diluted earnings (loss) per share:
Dividends		$0.37	$0.36	$0.31					$0.68	$1.08
Undistributed loss		($0.53)	($0.07)	($0.51)					($0.55)	($1.24)
Basic earnings (loss) per share		($0.15)	$0.30	($0.20)					$0.13	($0.16)
Undistributed loss		($0.53)	($0.07)	($0.51)					($0.55)	($1.24)
Class B Common Stock [Member]
Numerator for basic and diluted earnings (loss) per share:
Less: deemed dividends on Class B common shares		-7,222	-7,457						-7,457	-14,679	-21,901
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000	15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000									-15,555,000	-15,555,000
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000	15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000									-15,555,000	-15,555,000
Class B common stock-basic and diluted		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000	15,555,000	15,555,000
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000	15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000									-15,555,000	-15,555,000
Calculation of basic and diluted earnings (loss) per share:
Undistributed loss		($0.48)	($0.20)						($0.69)	($1.18)	($1.90)	($0.48)
Deemed dividends	$0.46	$0.46	$0.48						$0.48	$0.94	$1.41
Undistributed loss		($0.48)	($0.20)						($0.69)	($1.18)	($1.90)	($0.48)
Basic and diluted earnings (loss) per share	($0.23)	($0.02)	$0.28	($0.51)	($0.48)				($0.21)	($0.24)	($0.49)	($0.48)
Deemed dividends per Class B common share	$0.46	$0.46	$0.48						$0.48	$0.94	$1.41
Class B Common Stock [Member] | As Previously Reported [Member]
Numerator for basic and diluted earnings (loss) per share:
Less: deemed dividends on Class B common shares		($7,222)								($14,679)
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000		-15,555,000
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000		-15,555,000
Class B common stock-basic and diluted		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000
Add dilutive effect of:
Dilutive effect		15,555,000	15,555,000	15,555,000					15,555,000	15,555,000
Less: antidilutive securities
Antidilutive securities		-15,555,000		-15,555,000
Calculation of basic and diluted earnings (loss) per share:
Undistributed loss		($0.53)	($0.07)						($0.55)	($1.24)
Deemed dividends		$0.46								$0.94
Undistributed loss		($0.53)	($0.07)						($0.55)	($1.24)
Basic and diluted earnings (loss) per share		($0.06)	($0.07)	($0.51)					($0.55)	($0.30)
Deemed dividends per Class B common share		$0.46								$0.94

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended	12 Months Ended	0 Months Ended
In Millions, except Share data, unless otherwise specified	14-May-14	Dec. 31, 2014	Dec. 31, 2014	Feb. 24, 2015	Feb. 09, 2015
Subsequent Event [Member] | Pattern Development [Member]
Subsequent Event [Line Items]
Ownership interest					25.00%
Pre-Subsequent Event [Member] | Pattern Development [Member]
Subsequent Event [Line Items]
Ownership interest					35.00%
Class A Common Stock [Member]
Subsequent Event [Line Items]
Dividends payable, amount per share		$0.34	$0.34
Dividend declared date		29-Oct-14
Dividend payable date			30-Jan-15
Dividend payment, date of stockholders record			31-Dec-14
Common stock shares issued and sold	21,117,171
Class A Common Stock [Member] | Pattern Development [Member]
Subsequent Event [Line Items]
Common stock shares sold	10,306,361
Class A Common Stock [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends payable, amount per share				$0.34
Dividends payable amount per share annualized				$1.37
Percentage of increase in dividend				2.00%
Dividends payable amount per share quarterly				$0.34
Dividend declared date				24-Feb-15
Dividend payable date				30-Apr-15
Dividend payment, date of stockholders record				31-Mar-15
Common stock shares sold					12,000,000
Class A Common Stock [Member] | Subsequent Event [Member] | Follow On Public Offering [Member]
Subsequent Event [Line Items]
Common stock shares issued and sold					7,000,000
Net proceeds from issuance of shares					196.6
Class A Common Stock [Member] | Subsequent Event [Member] | Pattern Development [Member]
Subsequent Event [Line Items]
Common stock shares sold					5,000,000

Condensed_Financial_Informatio

Condensed Financial Information of Parent Balance Sheets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$101,656	$103,569	$17,574	$47,672
Related party receivable	671	167
Current deferred tax assets	318	573
Prepaid expenses and other current assets	27,954	11,415
Total current assets	208,956	160,035
Investments in subsidiaries	29,079	107,055
Net deferred tax assets	5,474	2,017
Other assets	12,678	13,243
Total assets	2,832,042	1,903,631
Current liabilities:
Accounts payable and other accrued liabilities	24,793	15,550
Related party payable	5,757	1,245
Dividend payable	15,734	11,103
Current deferred tax liabilities	149
Total current liabilities	262,067	96,619
Net deferred tax liabilities	20,418	9,930
Total liabilities	1,667,308	1,335,627
Equity:
Additional paid-in capital	723,938	489,412
Accumulated (loss) income	-44,626	-13,336
Accumulated other comprehensive loss	-53,913	-17,377	-45,506	-35,610
Total equity	1,164,734	568,004
Total liabilities and equity	2,832,042	1,903,631
Class A Common Stock [Member]
Equity:
Common stock value	621	355
Treasury stock, value	-717	-24
Class B Convertible Common Stock [Member]
Equity:
Common stock value		156
Pattern Energy Group Inc
Current assets:
Cash and cash equivalents	34,772	75,776	1
Related party receivable	1,982	1,000
Current deferred tax assets	307
Prepaid expenses and other current assets	4,484	446
Total current assets	41,545	77,222
Investments in subsidiaries	586,641	300,216
Investments in affiliates	29,079	107,055
Net deferred tax assets	147
Other assets	85	573
Total assets	657,497	485,066
Current liabilities:
Accounts payable and other accrued liabilities	6,404	4,513
Related party payable	757	667
Dividend payable	15,734	11,103
Current deferred tax liabilities	147
Total current liabilities	23,042	16,283
Net deferred tax liabilities	307	573
Total liabilities	23,349	16,856
Equity:
Additional paid-in capital	696,378	461,852
Capital	0	0
Accumulated (loss) income	-17,066	14,224
Accumulated other comprehensive loss	-45,068	-8,353
Total equity	634,148	468,210
Total liabilities and equity	657,497	485,066
Pattern Energy Group Inc | Class A Common Stock [Member]
Equity:
Common stock value	621	355
Treasury stock, value	-717	-24
Pattern Energy Group Inc | Class B Convertible Common Stock [Member]
Equity:
Common stock value		$156

Condensed_Financial_Informatio1

Condensed Financial Information of Parent Balance Sheets (Parenthetical) (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Class A Common Stock [Member]
Condensed Financial Statements, Captions [Line Items]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	62,088,306	35,531,720
Common stock, shares outstanding	62,062,841	35,530,786
Treasury stock, shares	25,465	934
Class A Common Stock [Member] | Pattern Energy Group Inc
Condensed Financial Statements, Captions [Line Items]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	62,088,306	35,531,720
Common stock, shares outstanding	62,062,841	35,530,786
Treasury stock, shares	25,465	934
Class B Convertible Common Stock [Member]
Condensed Financial Statements, Captions [Line Items]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	0	15,555,000
Common stock, shares outstanding	0	15,555,000
Class B Convertible Common Stock [Member] | Pattern Energy Group Inc
Condensed Financial Statements, Captions [Line Items]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	0	15,555,000
Common stock, shares outstanding	0	15,555,000

Condensed_Financial_Informatio2

Condensed Financial Information of Parent Statements of Operations and Comprehensive Income (Loss) (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Revenue	$79,418,000	$71,519,000	$65,007,000	$49,549,000	$41,767,000	$57,257,000	$58,712,000	$43,837,000	$265,493,000	$201,573,000	$114,528,000
Expenses									28,320,000	12,988,000	11,636,000
Operating income (loss)									54,981,000	47,728,000	19,022,000
Other income (expense):
Equity in earnings (loss) from subsidiaries									-25,295,000	7,846,000	-40,000
Related party income									2,612,000	665,000
Other expenses, net									433,000	2,496,000	1,320,000
Other (expense) income									-91,844,000	-33,110,000	-36,002,000
Net (loss) income before income tax									-36,863,000	14,618,000	-16,980,000
Tax provision									-3,136,000	-4,546,000	3,604,000
Net (loss) income	-15,986,000	-9,281,000	7,167,000	-21,899,000	-19,376,000	4,244,000	43,988,000	-18,784,000	-39,999,000	10,072,000	-13,376,000
Other comprehensive income (loss), net of tax
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax benefit (provision) of $1,855, ($615) and $302, respectively									-5,991,000	2,473,000	-1,475,000
Total other comprehensive (loss) income, net of tax									-36,536,000	31,039,000	-9,896,000
Comprehensive (loss) income									-68,005,000	42,910,000	-15,399,000
Pattern Energy Group Inc
Condensed Financial Statements, Captions [Line Items]
Revenue									0	0	0
Expenses									23,089,000	3,630,000	7,000
Operating income (loss)									-23,089,000	-3,630,000	-7,000
Other income (expense):
Equity in earnings (loss) from subsidiaries									18,064,000	12,641,000	-2,688,000
Equity in (loss) earnings from affiliates									-25,295,000	7,846,000	-40,000
Related party income									2,612,000	665,000
Other expenses, net									-3,566,000	-563,000
Other (expense) income									-8,185,000	20,589,000	-2,728,000
Net (loss) income before income tax									-31,274,000	16,959,000	-2,735,000
Tax provision									16,000
Net (loss) income									-31,290,000	16,959,000	-2,735,000
Other comprehensive income (loss), net of tax
Proportionate share of subsidiaries' other comprehensive (loss) income activity, net of tax benefit of $734, $0 and $0, respectively									-30,724,000	23,478,000	1,876,000
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax benefit (provision) of $1,855, ($615) and $302, respectively									-5,991,000	2,473,000
Total other comprehensive (loss) income, net of tax									-36,715,000	25,951,000	1,876,000
Comprehensive (loss) income									($68,005,000)	$42,910,000	($859,000)

Condensed_Financial_Informatio3

Condensed Financial Information of Parent Statements of Operations and Comprehensive Income (Loss) (Parenthetical) (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax (provision) benefit	$1,855	($615)	$302
Pattern Energy Group Inc
Condensed Financial Statements, Captions [Line Items]
Other Comprehensive Income (Loss), Net of Tax	734	0	0
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax (provision) benefit	$1,855	($615)	$302

Condensed_Financial_Informatio4

Condensed Financial Information of Parent Consolidated Statements of Cash Flows (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities
Net (loss) income	($39,999)	$10,072	($13,376)
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Stock-based compensation	4,105	511
Net loss on transactions	-16,526	-5,995	-4,173
Equity in (earnings) loss from subsidiaries	25,295	-7,846	40
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	12,916	-2,698	-5,842
Accounts payable and other accrued liabilities	3,667	3,036	-379
Related party receivable/payable	-942	190	-100
Net cash provided by operating activities	110,448	78,152	35,051
Investing activities
Net cash (used in) provided by investing activities	-379,380	72,391	-638,953
Financing activities
Proceeds from public offering, net of expenses	286,757	317,926
Proceeds from exercise of stock options	327
Repurchase of shares for employee tax withholding	-693	-24
Capital contributions-Pattern Development		32,679	281,519
Capital distributions-Pattern Development		-98,886	-114,236
Dividends paid	-52,344
Payment for deferred equity issuance costs	-550
Net cash provided by (used in) financing activities	268,989	-63,401	573,167
Net change in cash and cash equivalents	-1,913	85,995	-30,098
Cash and cash equivalents at beginning of period	103,569	17,574	47,672
Cash and cash equivalents at end of period	101,656	103,569	17,574
Pattern Energy Group Inc
Operating activities
Net (loss) income	-31,290	16,959	-2,735
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Stock-based compensation	4,105	511
Net loss on transactions	1,473
Equity in (earnings) loss from subsidiaries	-18,064	-12,641	2,688
Equity in loss (earnings) from affiliates	25,295	-7,846	40
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	-3,545	-446
Accounts payable and other accrued liabilities	1,999	93	7
Related party receivable/payable	-639	-1,007
Net cash provided by operating activities	-20,666	-4,377
Investing activities
Distribution from subsidiaries	108,581	233,226
Contribution to subsidiaries	-362,533	-172,130
Net cash (used in) provided by investing activities	-253,952	61,096
Financing activities
Proceeds from public offering, net of expenses	286,757	317,926
Proceeds from exercise of stock options	327
Repurchase of shares for employee tax withholding	-693	-24
Capital contributions-Pattern Development		32,678	1
Capital distributions-Pattern Development		-98,884
Capital distributions-Contribution Transactions		-232,640
Dividends paid	-52,344
Payment for deferred equity issuance costs	-433
Net cash provided by (used in) financing activities	233,614	19,056	1
Net change in cash and cash equivalents	-41,004	75,775	1
Cash and cash equivalents at beginning of period	75,776	1
Cash and cash equivalents at end of period	34,772	75,776	1
Schedule of non-cash activities
Investments in subsidiaries			$514,117