Pattern Energy 10-K 29 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 24, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	PEGI
Entity Registrant Name	Pattern Energy Group Inc.
Entity Central Index Key	1,561,660
Current Fiscal Year End Date	--12-31
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		74,643,763
Entity Public Float			$ 1,462,489,654

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 94,808	$ 101,656
Restricted cash	14,609	7,945
Trade receivables	45,292	35,759
Related party receivable	734	671
Reimbursable interconnection costs	38	2,532
Derivative assets, current	24,338	18,506
Current net deferred tax assets	0	318
Prepaid expenses	14,498	15,275
Other current assets	6,891	12,679
Deferred financing costs, current, net of accumulated amortization of $5,192 and $3,493 as of December 31, 2015 and 2014, respectively	2,121	1,747
Total current assets	203,329	197,088
Restricted cash	36,875	39,745
Turbine advances	0	79,637
Construction in progress	0	26,195
Property, plant and equipment, net of accumulated depreciation of $409,161 and $278,291 as of December 31, 2015 and 2014, respectively	3,294,620	2,350,856
Unconsolidated investments	116,473	29,079
Derivative assets	44,014	49,369
Deferred financing costs	4,572	5,166
Net deferred tax assets	6,804	5,474
Finite-lived intangible assets, net of accumulated amortization of $4,357 and $154 as of December 31, 2015 and 2014, respectively	97,722	1,257
Other assets	25,183	11,421
Total assets	3,829,592	2,795,287
Current liabilities:
Accounts payable and other accrued liabilities	42,776	24,793
Accrued construction costs	23,565	20,132
Related party payable	1,646	5,757
Accrued interest	9,035	3,634
Dividends payable	28,022	15,734
Derivative liabilities, current	14,343	16,307
Revolving credit facility	355,000	50,000
Current portion of long-term debt, net of financing costs of $3,671 and $11,868 as of December 31, 2015 and 2014, respectively	44,144	109,693
Current net deferred tax liabilities	0	149
Other current liabilities	2,156	4,000
Total current liabilities	520,687	250,199
Long-term debt, net of financing costs of $22,632 and $24,887 as of December 31, 2015 and 2014, respectively	1,174,380	1,304,165
Convertible senior notes, net of financing costs of $5,014 and $0 as of December 31, 2015 and 2014, respectively	197,362	0
Derivative liabilities	28,659	17,467
Net deferred tax liabilities	22,183	20,418
Finite-lived intangible liability, net of accumulated amortization of $2,168 and $0 as of December 31, 2015 and 2014, respectively	58,132	0
Other long-term liabilities	52,427	38,304
Total liabilities	$ 2,053,830	$ 1,630,553
Commitments and contingencies (Note 18)
Equity:
Class A common stock, $0.01 par value per share: 500,000,000 shares authorized; 74,644,141 and 62,062,841 shares outstanding as of December 31, 2015 and 2014, respectively	$ 747	$ 621
Additional paid-in capital	982,814	723,938
Accumulated loss	(77,159)	(44,626)
Accumulated other comprehensive loss	(73,325)	(45,068)
Treasury stock, at cost; 65,301 and 25,465 shares of Class A common stock as of December 31, 2015 and 2014, respectively	(1,577)	(717)
Total equity before noncontrolling interest	831,500	634,148
Noncontrolling interest	944,262	530,586
Total equity	1,775,762	1,164,734
Total liabilities and equity	$ 3,829,592	$ 2,795,287

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Deferred financing costs, current, accumulated amortization	$ 5,192	$ 3,493
Property, plant and equipment, accumulated depreciation	409,161	278,291
Accumulated amortization of finite-lived intangible assets	4,357	154
Current portion of long-term debt, financing costs	3,671	11,868
Long-term debt, financing costs	22,632	24,887
Financing costs - Convertible senior notes	5,014	0
Accumulated amortization of finite-lived intangible liability	$ 2,168	$ 0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares outstanding	74,644,141	62,062,841
Treasury stock, shares	65,301	25,465

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue:
Electricity sales	$ 324,275	$ 254,669	$ 178,796
Related party revenue	3,640	3,317	911
Other revenue	1,916	7,507	21,866
Total revenue	329,831	265,493	201,573
Cost of revenue:
Project expense	114,619	77,775	57,677
Depreciation, amortization and accretion	143,376	104,417	83,180
Total cost of revenue	257,995	182,192	140,857
Gross profit	71,836	83,301	60,716
Operating expenses:
General and administrative	29,807	22,533	4,819
Related party general and administrative	7,589	5,787	8,169
Total operating expenses	37,396	28,320	12,988
Operating income	34,440	54,981	47,728
Other (expense) income:
Interest expense	(77,907)	(67,694)	(63,614)
(Loss) gain on undesignated derivatives, net	(5,490)	(15,743)	13,502
Realized loss on designated derivatives	(11,221)	0	0
Equity in earnings (losses) in unconsolidated investments	16,119	(25,295)	7,846
Related party income	2,665	2,612	665
Early extinguishment of debt	(4,941)	0	0
Net (loss) gain on transactions	(3,400)	13,843	5,995
Other (expense) income, net	(929)	433	2,496
Total other expense	(85,104)	(91,844)	(33,110)
Net (loss) income before income tax	(50,664)	(36,863)	14,618
Tax provision	4,943	3,136	4,546
Net (loss) income	(55,607)	(39,999)	10,072
Net loss attributable to noncontrolling interest	(23,074)	(8,709)	(6,887)
Net (loss) income attributable to Pattern Energy	(32,533)	(31,290)	16,959
Loss per share information:
Net (loss) income attributable to Pattern Energy	(32,533)	(31,290)	16,959
Dividends declared on Class A common shares	(102,893)	(56,976)
Earnings allocated to participating securities	(32)	0	0
Undistributed loss attributable to common stockholders	(135,426)	(110,167)
Class A Common Stock [Member]
Loss per share information:
Dividends declared on Class A common shares	(102,861)	(56,976)	(11,103)
Undistributed loss attributable to common stockholders	$ (135,426)	$ (110,167)	$ (24,439)
Weighted average number of shares:
Weighted average number of shares - Basic and diluted (in shares)	70,535,568	42,361,959	35,448,056
Earnings Per Share, Basic	$ (0.46)	$ (0.56)
Loss per share
Dividends declared per Class A common share (in dollars per share)	$ 1.43	$ 1.30	$ 0.31
Class B Common Stock [Member]
Loss per share information:
Deemed dividends on Class B common shares	$ 0	$ (21,901)	$ 0
Weighted average number of shares:
Weighted average number of shares - Basic and diluted (in shares)	0	15,555,000	15,555,000
Loss per share
Basic and diluted loss per share (in dollars per share)	$ 0	$ (0.49)	$ (0.48)
Deemed dividends per Class B common share (in dollars per share)	$ 0	$ 1.41	$ 0

Consolidated Statements of Comp

Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (55,607)	$ (39,999)	$ 10,072
Other comprehensive (loss) income:
Foreign currency translation, net of zero tax impact	(28,947)	(10,875)	(8,309)
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit of $1,860, $1,138 and $0, respectively	(16,163)	(33,444)	24,932
Reclassifications to net loss due to termination/de-designation of interest rate derivatives, net of zero tax impact	17,139	0	0
Reclassifications to net loss, net of tax impact of $670, $404 and $0, respectively	12,234	13,774	11,943
Total change in effective portion of change in fair market value of derivatives	13,210	(19,670)	36,875
Proportionate share of equity investee's derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit (provision) of $2,394, $1,855 and ($615), respectively	(6,640)	(5,991)	2,473
Reclassifications to net loss, net of tax impact of $870, $0 and $0, respectively	2,412	0	0
Total change in effective portion of change in fair market value of derivatives	(4,228)	(5,991)	2,473
Total other comprehensive (loss) income, net of tax	(19,965)	(36,536)	31,039
Comprehensive (loss) income	(75,572)	(76,535)	41,111
Less comprehensive (loss) income attributable to noncontrolling interest:
Net loss attributable to noncontrolling interest	(23,074)	(8,709)	(6,887)
Derivative activity:
Effective portion of change in fair market value of derivatives, net of tax benefit of $185, $341 and $0, respectively	(1,740)	(3,422)	3,184
Reclassifications to net loss, net of tax impact of $201, $121 and 0, respectively	2,088	3,601	1,904
Total change in effective portion of change in fair market value of derivatives	348	179	5,088
Comprehensive loss attributable to noncontrolling interest	(22,726)	(8,530)	(1,799)
Comprehensive (loss) income attributable to Pattern Energy	$ (52,846)	$ (68,005)	$ 42,910

Consolidated Statements of Com6

Consolidated Statements of Comprehensive (Loss) Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Foreign currency translation, tax impact	$ 0	$ 0	$ 0
Effective portion of change in fair market value of derivatives, benefit	1,860	1,138	0
Reclassifications to net loss due to termination of interest rate derivatives, tax impact	0	0	0
Reclassifications to net loss, tax impact	670	404	0
Effective portion of change in fair market value of derivatives tax (provision) benefit - equity investee	2,394	1,855	(615)
Reclassifications to net loss, tax impact - equity investee	870	0	0
Effective portion of change in fair market value of derivatives, tax benefit - noncontrolling interest	185	341	0
Reclassifications to net loss, tax impact - noncontrolling interest	$ 201	$ 121	$ 0

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	Contribution Transactions [Member]	IPO [Member]	Class A Common Stock [Member]	Parent Company [Member]	Parent Company [Member]IPO [Member]	Common Stock [Member]Class A Common Stock [Member]	Common Stock [Member]Class A Common Stock [Member]Contribution Transactions [Member]	Common Stock [Member]Class A Common Stock [Member]IPO [Member]	Common Stock [Member]Class B Common Stock [Member]	Common Stock [Member]Class B Common Stock [Member]Contribution Transactions [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Contribution Transactions [Member]	Additional Paid-in Capital [Member]IPO [Member]	Capital [Member]	Capital [Member]Contribution Transactions [Member]	Accumulated Loss [Member]	Accumulated Loss [Member]Contribution Transactions [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2012	$ 589,412				$ 514,111		$ 0			$ 0		$ 0	$ 1			$ 545,471		$ 2,903		$ (34,264)	$ 75,301
Balance, shares at Dec. 31, 2012							(100)			0		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution	32,677				32,677											32,677
Distribution	(106,060)				(104,634)											(104,634)					(1,426)
Additional paid-in capital	2				2								2
Net (loss) income	(29,605)				(30,295)													(30,295)			690
Net current period other comprehensive (loss) income	24,192				20,633															20,633	3,559
Ending Balance at Oct. 01, 2013	569,828				493,084		$ 0			$ 0		$ 0	3			473,514		33,198		(13,631)	76,744
Balance, shares at Oct. 01, 2013							(100)			0		0
Beginning Balance at Dec. 31, 2012	589,412				514,111		$ 0			$ 0		$ 0	1			545,471		2,903		(34,264)	75,301
Balance, shares at Dec. 31, 2012							(100)			0		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared on Class A common stock				$ (11,103)
Deemed dividends on Class B convertible common stock	0
Net (loss) income	(10,072)
Net current period other comprehensive (loss) income	31,039
Ending Balance at Dec. 31, 2013	568,004				468,210		$ 355			$ 156		$ (24)	489,412			0		(13,336)		(8,353)	99,794
Balance, shares at Dec. 31, 2013							(35,531,720)			(15,555,000)		(934)
Beginning Balance at Oct. 01, 2013	569,828				493,084		$ 0			$ 0		$ 0	3			473,514		33,198		(13,631)	76,744
Balance, shares at Oct. 01, 2013							(100)			0		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Distribution	(232,640)				(232,640)								(232,640)
Interest in Gulf Wind retained by Pattern Development	0				(28,584)											(18,332)		(13,122)		2,870	28,584
Assumption of liabilities related to Contribution Transactions	4,207				4,207											4,207
Issuance of common stock	93	$ 0	$ 317,042		93	$ 317,042		$ 194	$ 160		$ 156		93	$ 470,701	$ 316,882		$ (450,975)		$ (20,076)
Issuance of common stock, shares							3,437	19,445,000	16,000,000		15,555,000
Issuance of Class A restricted common stock	156				156		$ 1						155
Issuance of Class A restricted common stock, shares							83,183
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)								(11,103)
Acquisition from Pattern Development	(57,852)				(57,852)								(54,942)							(2,910)
Distribution to noncontrolling interest	(866)																				(866)
Net (loss) income	19,533				13,336													13,336			6,197
Net current period other comprehensive (loss) income	6,847				5,318															5,318	1,529
Ending Balance at Dec. 31, 2013	568,004				468,210		$ 355			$ 156		$ (24)	489,412			0		(13,336)		(8,353)	99,794
Balance, shares at Dec. 31, 2013							(35,531,720)			(15,555,000)		(934)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock	286,893				286,893		$ 108						286,785
Issuance of common stock, shares							10,810,810
Issuance of Class A restricted common stock	3,496				3,496		$ 2						3,494
Issuance of Class A restricted common stock, shares							175,915
Issuance of Class A common stock upon exercise of stock options	327				327								327
Issuance of Class A common stock upon exercise of stock options, 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	0						$ 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 initial public offering	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)
Contribution from noncontrolling interests	406,163																				406,163
Increase in noncontrolling interests from business combinations	35,259															35,259		0			35,259
Distribution to noncontrolling interest	(2,100)															(2,100)		0			(2,100)
Net (loss) income	39,999				31,290													31,290			8,709
Net current period other comprehensive (loss) income	(36,536)				(36,715)															(36,715)	179
Ending Balance at Dec. 31, 2014	$ 1,164,734				634,148		$ 621			$ 0		$ (717)	723,938			0		(44,626)		(45,068)	530,586
Balance, shares at Dec. 31, 2014	(62,062,841)						(62,088,306)			0		(25,465)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock	$ 316,952				316,952		$ 124						316,828
Issuance of common stock, shares							12,435,000
Issuance of Class A common stock under equity incentive award plan	0						$ 2						(2)
Issuance of Class A common stock under equity incentive award plan, shares							186,136
Repurchase of shares for employee tax withholding	(860)				(860)							$ (860)
Repurchase of shares for employee tax withholding, shares												(39,836)
Stock-based compensation	4,462				4,462								4,462								0
Dividends declared on Class A common stock	(102,893)			$ (102,861)	(102,893)								(102,893)								0
Dividend equivalents declared upon vesting of deferred restricted stock units	(23)				23								23
Recognition of beneficial conversion feature on Class B convertible common stock	23,743				23,743								23,743
Buyout of noncontrolling interests	(86,276)				8,771								16,715			(88,747)		(14,244)		(7,944)	(95,047)
Deemed dividends on Class B convertible common stock	0
Contribution from noncontrolling interests	334,231																				334,231
Increase in noncontrolling interests from business combinations	205,100															205,100		0			205,100
Distribution to noncontrolling interest	(7,882)															(7,882)		0			(7,882)
Net (loss) income	55,607				32,533													32,533			23,074
Net current period other comprehensive (loss) income	(19,965)				(20,313)															(20,313)	348
Ending Balance at Dec. 31, 2015	$ 1,775,762				$ 831,500		$ 747			$ 0		$ (1,577)	$ 982,814			$ 0		$ (77,159)		$ (73,325)	$ 944,262
Balance, shares at Dec. 31, 2015	(74,644,141)						(74,709,442)			0		(65,301)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities
Net (loss) income	$ (55,607)	$ (39,999)	$ 10,072
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, amortization and accretion	143,376	104,417	83,180
Impairment loss	398	0	0
Amortization of financing costs	7,435	6,309	6,816
Loss (gain) on derivatives, net	2,219	15,546	(4,329)
Stock-based compensation	4,462	4,105	511
Net gain on transactions	0	(16,526)	(5,995)
Deferred taxes	4,494	2,948	4,546
Equity in (earnings) losses in unconsolidated investments	(16,180)	25,295	(7,846)
Unrealized loss on exchange rate changes	823	0	0
Amortization of power purchase agreements, net	1,946	0	0
Amortization of debt discount/premium, net	1,660	0	0
Realized loss on designated derivatives	11,221	0	0
Early extinguishment of debt	4,722	0	0
Changes in operating assets and liabilities:
Trade receivables	(2,254)	(8,255)	(8,721)
Reimbursable interconnection receivable	0	0	(11)
Prepaid expenses	1,272	(4,100)	(7,021)
Other current assets	(2,929)	17,016	4,323
Other assets (non-current)	(2,336)	(649)	(566)
Accounts payable and other accrued liabilities	4,716	3,667	3,036
Related party receivable/payable	711	(942)	190
Accrued interest payable	4,489	1,377	(33)
Contingent liabilities	515	0	0
Long-term liabilities	2,696	239	0
Increase in restricted cash	(2,120)	0	0
Decrease in restricted cash	2,120	0	0
Net cash provided by operating activities	117,849	110,448	78,152
Investing activities
Receipt of ITC Cash Grant	0	0	173,446
Cash paid for acquisitions, net of cash acquired	(433,792)	(306,584)	(30,070)
Proceeds from sale of investments	0	0	14,254
Decrease in restricted cash	62,583	46,700	66,517
Increase in restricted cash	(57,332)	(40,790)	(80,569)
Capital expenditures	(380,458)	(119,506)	(123,517)
Deferred development costs	0	0	(528)
Distribution from unconsolidated investments	38,240	22,019	10,463
Contribution to unconsolidated investments	(3)	(2,651)	(9,678)
Reimbursable interconnection receivable	2,494	3,892	49,715
Other assets	3,065	17,540	2,358
Net cash (used in) provided by investing activities	(765,203)	(379,380)	72,391
Financing activities
Proceeds from public offering, net of issuance costs	317,432	286,757	317,926
Proceeds from issuance of convertible senior notes, net of issuance costs	218,929	0	0
Proceeds from exercise of stock options	0	327	0
Repurchase of shares for employee tax withholding	(860)	(693)	(24)
Dividends paid	(90,582)	(52,344)	0
Payment for acquisitions from Pattern Development	0	0	(49,430)
Capital distributions - Contribution Transactions	0	0	(232,640)
Capital contributions - Pattern Development	0	0	32,679
Capital distributions - Pattern Development	0	0	(98,886)
Payment for deferred equity issuance costs	0	(550)	0
Buyout of noncontrolling interests	(121,224)	0	0
Capital contributions - noncontrolling interest	336,043	200,805	0
Capital distributions - noncontrolling interest	(7,882)	(2,100)	(2,292)
Decrease in restricted cash	56,218	19,627	122,689
Increase in restricted cash	(54,592)	(17,903)	(127,369)
Refund of deposit for letters of credit	3,425	(3,422)	0
Payment for deferred financing costs	(13,667)	(11,856)	(294)
Proceeds from revolving credit facility	405,000	50,000	56,000
Repayment of revolving credit facility	(100,000)	0	(56,000)
Proceeds from construction loans	329,070	59,778	0
Proceeds from long-term debt	164,973	0	138,620
Repayment of long-term debt	(785,923)	(259,437)	(164,380)
Payment for interest rate derivatives	(11,061)	0	0
Net cash provided by financing activities	645,299	268,989	(63,401)
Effect of exchange rate changes on cash and cash equivalents	(4,793)	(1,970)	(1,147)
Net change in cash and cash equivalents	(6,848)	(1,913)	85,995
Cash and cash equivalents at beginning of period	101,656	103,569	17,574
Cash and cash equivalents at end of period	94,808	101,656	103,569
Supplemental disclosures
Cash payments for income taxes	342	131	0
Cash payments for interest expense, net of capitalized interest	62,607	53,776	53,295
Acquired property, plant and equipment from acquisitions	581,834	1,013,365	0
Equity issuance costs paid in prior period related to current period offerings	(433)	0	(884)
Schedule of non-cash activities
Change in fair value of designated interest rate swaps	13,210	(22,847)	36,875
Change in property, plant and equipment	15,695	(47,908)	(109,281)
Non-cash deemed dividends on Class B convertible common stock	0	21,901	0
Non-cash increase in additional paid-in capital from buyout of noncontrolling interests	16,715	0	0
Amortization of deferred financing costs—included as construction in progress	0	343	175
Transfer of capitalized assets to South Kent joint venture	0	0	49,275
Non-cash distribution to Pattern Development	0	0	(5,748)
Assumption of contingent liability related to Contribution Transactions	0	0	(4,207)
Assumption of contingent liability upon acquisition of Logan’s Gap	$ 0	$ (4,000)	$ 0

Organization

Organization	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Organization	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 October 2, 2013, concurrent with the initial public offering, the Company issued to Pattern Development 19,445,000 shares of Class A common stock, representing 63% of the Company's Class A common stock outstanding at the time, and 15,555,000 shares of Class B common stock. On December 31, 2014, the Company’s outstanding Class B common stock was converted into Class A common stock on a one-for-one basis . As a result, the shares of Class B common stock were retired and the Company is no longer authorized to issue shares of Class B common stock. On May 14, 2014, the Company completed an underwritten public offering of its Class A common stock resulting in a reduction of Pattern Development’s interest in the Company from approximately 63% to 35% . Consequently, the Company is no longer subject to Accounting Standards Codification ("ASC") 805-50-30-5, Transactions between Entities under Common Control. All transactions with Pattern Development after May 14, 2014 are recognized at fair value on the measurement date in accordance with the ASC 805, Business Combinations . On February 9, 2015, the Company completed an underwritten public offering of its Class A common stock, resulting in a further reduction of Pattern Development’s interest in the Company from 35% to 25% causing it to no longer be entitled to certain approval rights pursuant to the Shareholder Approval Rights Agreement dated October 2, 2013. Refer to Note 15, Stockholders' Equity - Common Stock , for additional information on equity transactions that occurred during the year. 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, except for purchases of Lost Creek, Post Rock and certain additional interests in El Arrayán (each as defined below, which were purchased from third-parties). Each of the Company's wind projects are consolidated into the Company's subsidiaries which are organized by geographic location: Pattern US Operations Holdings LLC, Pattern Canada Operations Holdings ULC and Pattern Chile Holdings LLC. 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"), Pattern Gulf Wind LLC ("Gulf Wind") and Lost Creek Wind, LLC ("Lost Creek") and owns a controlling interest in Pattern Panhandle Wind LLC ("Panhandle 1"), Pattern Panhandle Wind 2 LLC ("Panhandle 2"), Post Rock Wind Power Project, LLC ("Post Rock"), Logan's Gap Wind LLC ("Logan's Gap") and Fowler Ridge IV Wind Farm LLC ("Amazon Wind Farm Fowler Ridge"), all of which are consolidated into Pattern US Operations Holdings LLC. The Company also owns a controlling interest in Parque Eólico El Arrayán SpA ("El Arrayán") which is consolidated into Pattern Chile Holdings LLC, and noncontrolling interests in South Kent Wind LP ("South Kent"), Grand Renewable Wind LP ("Grand") and K2 Wind Ontario Limited Partnership ("K2"), which are accounted for as equity method investments in Pattern Canada Operations Holdings ULC. 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. In accordance with ASC 805-50-30-6, Transactions Between Entities Under Common Control , 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.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	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. Change in Depreciable Lives of Property, Plant and Equipment The Company periodically reviews the estimated economic useful lives of its fixed assets. In 2015, based on technical review of various wind farm characteristics, the expected economic useful lives of certain wind farms were longer than the estimated economic useful lives used for depreciation purposes in the Company’s financial statements. As a result, effective January 1, 2015, the Company changed its estimate of the economic useful lives of wind farms for which construction began after 2011, from 20 to 25 years. All other wind farms continue to depreciate over an estimated economic useful life of 20 years. For the year ended December 31, 2015 , the effect of this change reduced depreciation expense by $14.7 million , decreased net loss by $13.9 million , net of tax, and decreased Class A basic and diluted loss per share by $0.09 . Reclassification Certain prior period balances have been reclassified to conform to the current period presentation in the Company’s consolidated financial statements and the accompanying notes. The Company has also revised its consolidated statements of comprehensive income (loss) for the years December 31, 2014 and 2013 to correct an immaterial classification error. The consolidated statements of comprehensive income (loss) for the years ended December 31, 2014 and 2013 have been corrected to reflect the reclassification of approximately $27.5 million and $23.9 million , respectively, between the effective portion of change in fair market value of derivatives and reclassification to net loss attributable to Pattern Energy. The consolidated statements of comprehensive income (loss) for the years ended December 31, 2014 and 2013 have also been corrected to reflect the reclassification of approximately $7.2 million and $3.8 million , respectively, between the effective portion of change in fair market value of derivatives and reclassification to net loss for noncontrolling interest. These revisions had no impact on comprehensive loss or comprehensive loss attributable to noncontrolling interest. Changes in accumulated other comprehensive loss by component, as disclosed in Note 12 , Accumulated Other Comprehensive Loss , have also been corrected to reflect this immaterial error correction. 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, including contingent consideration, 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. Transaction costs associated with business combinations are expensed as incurred. Asset Acquisitions When the Company acquires assets and liabilities that do not constitute a business, the fair value of the purchase consideration, including transaction costs of the asset acquisition, is assumed to be equal to the fair value of the net assets acquired and is allocated to the individual assets and liabilities assumed based on their relative fair values. Contingent consideration associated with the acquisition is generally recognized when the contingency is resolved. No goodwill is recognized in an asset acquisition. Transaction costs associated with asset acquisitions are capitalized as part of the investment. Equity Method Investments When the Company acquires a noncontrolling interest in an entity where it is not the primary beneficiary, does not control any of the ongoing activities of the entity, and does not meet consolidation requirements of ASC 810, Consolidation of Variable Interest Entities, the investment is initially recognized as an equity method investment at cost. Any basis difference related to the property, plant and equipment will be amortized over the estimated economic useful life of the underlying long-lived assets. A basis difference related to the PPA will be amortized over the remaining term of the PPA. Transactions costs associated with equity method investments are capitalized as part of the investment. Noncontrolling Interests Noncontrolling interests represent the portion of the Company’s net income (loss), net assets and comprehensive income (loss) that is not allocable to the Company and is calculated based on ownership percentage, for applicable projects. For the noncontrolling interests in the Company’s Panhandle 1, Panhandle 2, Post Rock, Logan's Gap and Amazon Wind Farm Fowler Ridge projects, and the Company's Gulf Wind project prior to the acquisition of the noncontrolling interests in July 2015, 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 the projects were liquidated at recorded amounts determined in accordance with U.S. GAAP and distributed to the investors. The noncontrolling interest in the results of operations and comprehensive income (loss) 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 the projects and the third party. The noncontrolling interest balances in the projects 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 income (loss), net of tax, in the accompanying consolidated statements of stockholders’ equity and comprehensive income (loss). Where the U.S. dollar is the functional currency, re-measurement adjustments are recorded in other (expense) 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, reimbursable interconnection costs and derivative instruments. The Company’s cash and cash equivalents are with high quality 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; however, the Company believes that its credit risk is immaterial. In addition, reimbursable interconnection costs are with large creditworthy utility companies and the Company’s derivative instruments are placed with counterparties that are creditworthy institutions. The Company sells electricity and RECs primarily to creditworthy utilities under long-term, fixed-priced power sale arrangements ("PSAs"). During the year ended December 31, 2015 , Standard & Poor’s Rating Services ("S&P") further downgraded the credit rating of the Puerto Rico Electric Power Authority ("PREPA") from CCC to CC. Through December 31, 2015 , Moody’s Investor Service’s credit rating of PREPA remains unchanged at Caa3. As of February 29, 2016 , 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 18, 2016 . The table below presents significant customers who accounted for greater than 10% of total revenue, and PREPA, and the related maximum amount of credit loss based on their percentages of total trade receivables as of December 31, 2015 , 2014 and 2013 : Year ended December 31, 2015 2014 2013 Revenue Trade Receivables Revenue Trade Receivables Revenue Trade Receivables San Diego Gas & Electric 17.07 % 17.03 % 22.09 % 14.13 % 16.31 % 26.21 % PREPA 8.42 % 8.80 % 9.29 % 6.91 % 8.21 % 16.88 % The Independent Electricity System Operator ("IESO") of Ontario, Canada is the customer for each of the Company’s Grand, K2 and South Kent projects. The Company accounts for these projects under the equity method of accounting and as a result, the Company’s ownership interest in these projects is recorded in equity in earnings (losses) in unconsolidated investments and not in revenue. As such, IESO is not included in the foregoing table of significant customers. However, we rely on a limited number of key power purchasers, including IESO, and face a concentration of credit risk from IESO as a customer. 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 which may 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 13 , 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 4 , Property, Plant and Equipment . Cash and Cash Equivalents Cash and cash equivalents consist of cash balances and highly-liquid investments with original maturities of three months or less. 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, PSAs 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, primarily to creditworthy utilities. The Company believes that all amounts are collectible and an allowance for doubtful accounts is not required as of December 31, 2015 and 2014 . 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 either when the project reaches commercial operation or as energy is delivered over the life of the PPA. 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. 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. 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. The Company begins capitalizing deferred development costs as a component of construction in progress on the date the project commences construction. Once the project achieves commercial operation, the Company reclassifies the amounts recorded in construction in progress to property, plant and equipment. Finite-Lived Intangible Assets and Liability Finite-lived intangible assets include PPAs, easements, land options and mining rights. PPAs obtained through acquisitions are valued at the time of acquisition and the difference between the contract price and the estimated fair value results in an intangible asset or an intangible liability. If the contract price is higher than the estimated fair value, the Company will recognize an intangible asset. If the contract price is lower than the estimated fair value, the Company will recognize an intangible liability. Easements, land options and mining rights are recognized at the carryover basis from the seller. The Company amortizes its intangible asset and liability associated with PPAs using the straight-line method over the remaining term of the related PPA. At the date of acquisition, the weighted average amortization period of the intangible asset associated with the PPA is approximately 15 years and the weighted average amortization period of the intangible liability is approximately 17 years. The Company amortizes easements, land options and mining rights 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 approximately 5 - 25 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 for which construction began before 2011 are depreciated over 20 years and wind farms for which construction began after 2011 are depreciated over 25 years . The remaining assets are depreciated over two to five years. 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. During the year ended December 31, 2015 , the Company recorded impairment charges of $0.4 million related to the write-off of certain furniture, fixtures and equipment in project expenses in the consolidated statements of operations. Derivatives The Company may enter into interest rate swaps, interest rate caps, forwards and other agreements to manage its interest rate, electricity price and foreign exchange rate risk. 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. The Company does not have contracts subject to master netting agreements with counterparties, as such assets and liabilities are presented gross on the consolidated balance sheets. Contracts used in normal business operations that are settled by physical delivery, among other criteria, are eligible for and may be designated as NPNS. NPNS contracts do not meet the definition of derivatives, and therefore, contracts associated with the sale of energy are recognized as electricity sales and contracts associated with the production of electricity are recognized as project expense on the consolidated statements of operations. Accounting for changes in the fair value 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 qualify and 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 income (loss) ("OCI"), until the contract settles and the hedged item is recognized in earnings. The ineffective portion of change in fair value is recorded as a component of net income (loss) on the consolidated statements of operations. The Company discontinues hedge accounting when it has determined that a derivative contract no longer qualifies as an effective hedge or when it is no longer probable that the hedged forecasted transaction will occur. When the Company discontinues hedge accounting, associated deferred amounts are immediately recognized into earnings and future changes in fair value, if any, are recognized in earnings. For undesignated derivative instruments, the change in fair value is reported as a component of net income (loss) on the consolidated statements of operations. 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. Deferred financing costs are capitalized and recorded as an offset to the respective loans in the Company's consolidated balance sheets and are amortized to interest expense in the consolidated statements of operations. Financing costs related to the revolving credit facility are capitalized and recorded as a long-term asset in the Company's consolidated balance sheets and are amortized to interest expense in the Company's consolidated statements of operations, over the life of its life using the effective-interest method. Income Taxes 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, Income Taxes, 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% 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 either acquired through business combinations or asset acquisitions. Contingent obligations that are acquired through business combinations are recorded at fair value on the date of acquisition while contingent obligations that are acquired through asset acquisitions are recorded generally when the contingency is resolved. The Company’s contingent liabilities related to turbine availability warranties with turbine manufacturers and turbine availability guarantees associated with long-term turbine service arrangements are reported at net realizable value. Pursuant to these warranties and guarantees, if a turbine operates at less than minimum availability during the warranty or guarantee period, the manufacturer or service provider is obligated to pay, as liquidated damages, an amount for each percent that the turbine operates below the minimum availability threshold. In addition, pursuant to certain of these warranties and guarantees, if a turbine operates at more than a specified availability during the warranty or guarantee period, the Company has an obligation to pay a bonus to the turbine manufacturer or service provider. Asset Retirement Obligation The Company records asset retirement obligations ("AROs") for the estimated costs of decommissioning turbines, removing above-ground installations and restoring sites, at the time when a contractual decommissioning obligation is incurred. AROs represent the present value of the expected costs and timing of the related decommissioning activities. The ARO assets and liabilities are recorded in property, plant and equipment and other long-term liabilities, respectively, in the consolidated balance sheets. 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 consolidated statements of operations using accretion rates based on credit adjusted risk-free interest rates. Changes resulting from revisions to the timing or amount of the original estimate of cash flows are recognized as an increase or a decrease in the asset retirement cost, or income when the asset retirement cost is depleted. Revenue Recognition The Company sells electricity and related renewable energy credits under the terms of the PSAs or at market prices. Revenue is recognized based upon the amount of electricity delivered at rates specified under the contracts, or at market prices for spot market transactions, assuming all other revenue recognition criteria are met. When renewable energy credits are sold as a separate component, revenue is recognized at the time title to the energy credits is transferred to the buyer. Depending on the terms of the PSA, the Company may account for the contracts as operating leases pursuant to ASC 840, Leases , or derivative instruments pursuant to ASC 815, Derivatives and Hedging . In considering ASC 840 , Leases , it was determined that certain of the Company's PSAs are operating leases. ASC 840, Leases , requires minimum lease payments to be recognized over the term of the lease and contingent rents to be recorded when the achievement of the contingency becomes probable. All energy sales under the PSAs are considered contingent rent due to the inherent uncertainty and variability. None of the operating leases have minimum lease payments; therefore, revenue from these contracts and any related renewable energy attributes are recognized as electricity sales when delivered. Contracts that meet the NPNS scope exception to derivative accounting are accounted for under the accrual method, where revenues are recorded in the period they are earned. Energy derivative instruments that reduce exposure to changes in commodity prices may allow the Company to lock in a fixed price per MWh for a specified amount of annual electricity generation over the life of the swap contract. Monthly settlement amounts under energy hedges are accounted for as energy derivative settlements in the consolidated statements of operations. Changes in the fair value of energy hedges are recorded in electricity sales 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 Black-Scholes option pricing model includes assumptions regarding dividend yields, expected volatility, expected option term, expected forfeiture rate and risk-free interest rates. Expense is recognized by amortizing the fair value of the stock options granted using a straight-line method over the applicable vesting period; accordingly, stock based compensation is netted for estimated forfeitures. 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 and restricted stock unit grants by amortizing the fair value of the restricted stock award grants, which is the grant date market price, over the applicable vesting period. For certain restricted stock award grants, the Company measures the fair value at the grant date using a Monte Carlo simulation model and amortizes the fair value over the longer of the requisite period or performance period. The Monte Carlo simulation model includes assumptions regarding dividend yields, expected volatility, risk-free interest rates and initial total shareholder return ("TSR") performance. Stock-based compensation expense is recorded as a component of general and administrative expenses in the Company’s consolidated statements of operations. Comprehensive Income (Loss) Comprehensive income (loss) consists of net income (loss) and other comprehensive income (loss), net of tax. Other comprehensive income (loss), net of tax included in accumulated other comprehensive income (loss) in the accompanying consolidated statements of stockholders’ equity, is comprised primarily of changes in foreign currency translation adjustments and the effective portion of changes in the fair value of derivatives designated as hedges. Segment Data and Geographic Information 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 resourc

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Acquisitions	Acquisitions Business Combinations Wind Capital Group Acquisition On May 15, 2015, pursuant to a Purchase and Sale Agreement, the Company acquired 100% of the membership interests in Lost Creek Wind Finco, LLC ("Lost Creek Finco") from Wind Capital Group LLC, an unrelated third party, and 100% of the membership interests in Lincoln County Wind Project Holdco, LLC ("Lincoln County Holdco") from Lincoln County Wind Project Finco, LLC, an unrelated third party. Lost Creek Finco owns 100% of the Class B membership interests in Lost Creek Wind Holdco, LLC (“Lost Creek Wind Holdco”), a company which owns a 100% interest in the Lost Creek wind project. Lincoln County Holdco owns 100% of the Class B membership interests in Post Rock Wind Power Project, LLC, a company which owns a 100% interest in the Post Rock wind project. The acquisition of 100% of the membership interests in Lost Creek Finco and Lincoln County Holdco was for an aggregate consideration of approximately $242.0 million , paid at closing. The Company also assumed certain project level indebtedness and ordinary course performance guarantees securing project obligations. Lost Creek is a 150 MW wind project in King City, Missouri, and Post Rock is a 201 MW wind project in Ellsworth and Lincoln Counties, Kansas. The Company acquired assets and operating contracts for Lost Creek and Post Rock, including assumed liabilities. The identifiable assets and liabilities assumed were recorded at their fair values, which corresponded to the sum of the cash purchase price and the fair value of the other investors’ noncontrolling interests. The fair value of the assets acquired and liabilities assumed in connection with the acquisition are as follows (in thousands): May 15, 2015 Cash and cash equivalents $ 3,501 Restricted cash, current 11,787 Trade receivables 7,910 Prepaid expenses 1,232 Other current assets 444 Restricted cash 4,592 Property, plant and equipment 543,347 Finite-lived intangible assets 97,400 Other assets 17,632 Accounts payable and other accrued liabilities (2,611 ) Accrued interest (951 ) Derivative liabilities, current (3,759 ) Current portion of long-term debt, net of financing costs (7,463 ) Finite-lived intangible liabilities (60,300 ) Asset retirement obligations (7,192 ) Long-term debt, net of financing costs (108,838 ) Derivative liabilities (14,631 ) Total consideration before temporary equity and noncontrolling interests 482,100 Less: temporary equity (35,000 ) Less: noncontrolling interests (205,100 ) Total consideration after temporary equity and noncontrolling interests $ 242,000 Current assets, non-current restricted cash, accounts payable and other accrued liabilities and accrued interest were recorded at carrying value, which is representative of the fair value on the date of acquisition. Property, plant and equipment, finite-lived intangible asset, finite-lived intangible liability and debt were recorded at fair value estimated using the income approach. The fair values of other assets, derivatives and asset retirement obligations were recorded at fair value using a combination of market data, operational data and discounted cash flows and were adjusted by a discount rate factor reflecting current market conditions at the time of acquisition. The noncontrolling interest in Post Rock was recorded at fair value estimated using a projected cash flow stream of distributable cash and tax benefits anticipated based on the existing Partnership Agreement, discounted to present value with a discount rate reflecting the estimated return on investment required by participants in the tax equity market. The noncontrolling interest in Lost Creek was recorded at fair value estimated using the purchase price from a purchase agreement executed on May 15, 2015 between the Company and the tax equity investor. 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). During the three months ended December 31, 2015, the Company adjusted the initial valuation and increased property, plant and equipment by $2.0 million and decreased other assets by $2.3 million . Additionally, the Company increased asset retirement obligations and other accrued liabilities by $0.2 million and decreased derivatives liabilities, current by $0.5 million . These changes are as a result of the updated inputs, assumptions and methodologies used in determining the fair value of these assets and liabilities. The Company incurred transaction-related expenses of $1.7 million which were recorded in net gain (loss) on transactions in the consolidated statements of operations for the year ended December 31, 2015 . On July 30, 2015, the Company acquired 100% of the Class A membership interests in Lost Creek Wind Holdco for a cash purchase price of approximately $35.2 million . As a result, Lost Creek became wholly owned as of July 30, 2015. 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. Below is a description of the allocation of distributions related to the Post Rock. Allocation of Distributions In accordance with the terms of the operating agreement of Post Rock, prior to the earlier of the flip point (the point at which the Class A Members have realized a specified internal rate of return) or November 20, 2023, the Class A Members shall receive 40% of all distributions from Post Rock. If the flip point has not occurred by November 20, 2023, then prior to the earlier of the flip point or November 20, 2027, the Class A Members shall receive 60% of all distributions from Post Rock. If the flip point has not occurred by November 20, 2027, the Class A Members shall receive 100% of all distributions from Post Rock until the flip point occurs. After the flip point, the Class A Members will receive 10% of the distributions, but not less than the amount that will offset certain Class A Member tax liabilities. In each case, the Class B Member will receive the remainder of all distributable cash, provided that distributions related to certain payments under a Build Out Agreement between Post Rock and the Company are made to the Class A members. Allocation of Tax Items Prior to the flip point, Post Rock's tax items consisting of income, gain, loss and deductions, or the Tax Items, are allocated as follows: prior to the flip point, 99% of the Tax Items are allocated to the Class A Members and 1% to the Class B Member. After the flip point, the Class A Members receive 10% of the Tax Items and the balance will be received by the Class B Member. Tax items attributable to the liquidation of derivative contracts are allocated 4.95% to the Class A Members and 95.05% to the Class B Member. 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 achieved commercial operation in September 2015, and is located in Comanche County, Texas. The construction of the project was being financed primarily by construction debt and the Company. Following construction, the institutional tax equity investors invested in the project, pursuant to an executed equity commitment agreement, so that the construction loan was paid and that long term financing for the project is equity based. Following the achievement of commercial operation, in September 2015, the Company and certain tax equity investors made capital contributions to fund the repayment of the Logan's Gap construction loan. As a result, the Company and the tax equity investors hold 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 accounting for the Logan’s Gap acquisition was completed as of March 31, 2015 at which point the fair values became final. The following table summarizes the provisional amounts recognized for assets acquired and liabilities assumed as of December 19, 2014, as well as adjustments made through March 31, 2015, when the allocation became final. During the quarter ended March 31, 2015, the Company adjusted the initial valuation and increased prepaid expenses and other current assets by $0.1 million , increased deferred financing costs, current by $0.8 million , increased construction in progress by $0.1 million and increased accrued construction costs by $0.9 million . 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 1,790 Deferred financing costs, current 2,882 Construction in progress 23,821 Property, plant and equipment 116 Other assets 80 Accrued construction costs (5,617 ) 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 the acquisition of the project. As of December 31, 2015, $6.3 million of the contingent obligation has been paid with the remaining $1.7 million payable recorded in accounts payable and other accrued liabilities. The Company incurred $0.1 million and $0.3 million of transaction-related expenses which were recorded in net gain (loss) on transactions in the consolidated statements of operations for the years ended December 31, 2015 and 2014, respectively. 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. Below is a description of the allocation of distributions related to Logan's Gap. Allocation of Distributions In accordance with the terms of the operating agreement of Logan’s Gap, prior to the earlier of the flip point (the point at which the Class A Members have realized a specified internal rate of return) or December 17, 2024, the Class A Members shall receive approximately 18% of all distributions from Logan’s Gap. After the flip point, the Class A Members will receive 5.1% of the distributions, but not less than the amount that will offset certain Class A Member tax liabilities. In each case, the Class B Member will receive the remainder of all distributable cash. Distributions related to the sale of RECs are made primarily to the Class B Member. Allocation of Tax Items Prior to the flip point, Logan’s Gap's tax items consisting of income, gain, loss and deductions, or the Tax Items, are allocated as follows: prior to the flip point, 99% of the Tax Items are allocated to the Class A Members and 1% to the Class B Member. After the flip point, the Class A Members receive 5.1% of the Tax Items and the balance will be received by the Class B Member. Tax items related to the sale of RECs are allocated primarily to the Class B Member. 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 . Concurrent with 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 interest, 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 operation on November 7, 2014 . 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. Since the closing of the tax equity event occurred simultaneously with the acquisition, the Company considered the price paid by the noncontrolling investors (an entry price) to be a clear indication of what a market participant would pay and a reasonable measurement of fair value (an exit price) of the noncontrolling interest at initial recognition. The short-term debt presented in the table below consists of a construction loan that was repaid in full following the acquisition. The accounting for the Panhandle 2 acquisition was completed as of March 31, 2015 at which point the fair values became final. The following table summarizes the final amounts recognized for assets acquired and liabilities assumed as of November 10, 2014. 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 Company incurred $0.2 million and $0.6 million of transaction-related expenses which were recorded in net gain (loss) on transactions in the consolidated statements of operations for the years ended December 31, 2014 and 2013, respectively. 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. Below is a description of the allocation of distributions related to the Panhandle 2. Allocation of Distributions In accordance with the terms of the operating agreement of Panhandle 2, prior to the earlier of the flip point (the point at which the Class A Members have realized a specified internal rate of return) or November 30, 2023, the Class A Members shall receive approximately 19% of all distributions from Panhandle 2. If the amount of distributions is below a determined schedule, the Class A Members shall receive 40% of distributable cash and the Class B Member shall receive the remainder of distributable cash. After the flip point, the Class A Members will receive 5% of the distributions, but not less than the amount that will offset certain Class A Members’ tax liabilities. In each case, the Class B Member will receive the remainder of all distributable cash. Distributions related to the sale of RECs are made primarily to the Class B Member. Allocation of Tax Items Prior to the flip point, Panhandle 2’s tax items consisting of income, gain, loss and deductions, or the Tax Items, are allocated as follows: 99% of the Tax Items are allocated to the Class A Members and 1% to the Class B Member. After the flip point, the Class A Members receive 5% , and the balance will be received by the Class B Member. Tax items related to the sale of RECs are allocated primarily to the Class B Member. Panhandle 1 Acquisition On June 30, 2014 , the Company acquired 100% of the Class B membership interest 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 operation on June 25, 2014. Concurrent with 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 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. Since the closing of the tax equity event occurred simultaneously with the acquisition, the Company considered the price paid by the noncontrolling investors (an entry price) to be a clear indication of what a market participant would pay and a reasonable measurement of fair value (an exit price) of the noncontrolling interest at initial recognition. The accounting for the Panhandle 1 acquisition was completed as of December 31, 2014 at which point the fair values became final. The following table summarizes the provisional amounts recognized for assets acquired and liabilities assumed as of June 30, 2014, as well as adjustments made through December 31, 2014, when the allocation became final. 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 expenses which were recorded in net gain (loss) on transactions in the consolidated statements of operations for the year ended December 31, 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. Below is a description of the allocation of distributions related to Panhandle 1. Allocation of Distributions In accordance with the terms of the operating agreement of Panhandle 1, prior to the earlier of the flip point (the point at which the Class A Members have realized a specified internal rate of return) or June 29, 2023, the Class A Members shall receive approximately 21% of all distributions from Panhandle 1. After the flip point, the Class A Members will receive 5% of the distributions, but not less than the amount that will offset certain Class A Member tax liabilities. In each case, the Class B Member will receive the remainder of all distributable cash. Distributions related to the sale of RECs are made primarily to the Class B Member. Allocation of Tax Items Prior to the flip point, Panhandle 1's tax items consisting of income, gain, loss and deductions, or the Tax Items, are allocated as follows: prior to the flip point, 99% of the Tax Items are allocated to the Class A Members and 1% to the Class B Member. After the flip point, the Class A Members receive 5% of the Tax Items and the balance will be received by the Class B Member. Tax items related to the sale of RECs are allocated primarily to the Class B Member. 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, located in Ovalle, Chile, which achieved commercial operation 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 (loss) 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. In accordance with ASC 805, the Company considered whether any control premium or noncontrolling interest discount adjustment was necessary; however, based upon the relevant facts, the Company concluded that a proportionate allocation of the total fair value was reasonable. Therefore, no control premium or noncontrolling interest discount was applied in calculating the fair value of the Company's equity interest. 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 accounting for the AEI El Arrayán acquisition was completed as of December 31, 2014 at which point the fair values became final. The following table summarizes the final amounts recognized for assets acquired and liabilities assumed as of June 25, 2014. 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, accounts payable and other accrued 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. Debt and 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 (loss) on transactions in the consolidated statements of operations for the year ended December 31, 2014. Supplemental pro forma data (unaudited) The unaudited pro forma statements of operations data below gives effect to the Lost Creek, Post Rock, Logan's Gap, Panhandle 2, Panhandle 1, and El Arrayán acquisitions as if they had occurred on January 1, 2014. The pro forma net loss for the years ended December 31, 2015 and 2014 was adjusted to exclude nonrecurring transaction related expenses of $1.8 million and $2.9 million , respectively. In addition, the 2014 pro forma net loss was adjusted to exclude a nonrecurring gain of $17.9 million , upon the acquisition of AEI 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, 2014. 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) 2015 2014 Pro forma total revenue $ 351,094 $ 326,094 Pro forma total expenses 411,746 389,180 Pro forma net loss (60,652 ) (63,086 ) Less: pro forma net loss attributable to noncontrolling interest (29,091 ) (21,591 ) Pro forma net loss attributable to Pattern Energy $ (31,561 ) $ (41,495 ) Prior to the acquisition of AEI El Arrayán, net loss was recorded in equity in (losses) earnings in unconsolidated investments in the consolidated statements 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 Lost Creek and Post Rock since their respective dates of acquisition: Year ended December 31, Unaudited data (in thousands) 2015 Total revenue $ 31,093 Total expenses 34,574 Net loss (3,481 ) Less: net loss attributable to noncontrolling interest (5,114 ) Net loss attributable to Pattern Energy $ 1,633 Noncontrolling Interest Acquisition Gulf Wind On July 28, 2015, the Company acquired Pattern Development’s 27% interest in the Gulf Wind project for a cash purchase price of approximately $ 13.0 million . Concurrently, the Company acquired 100% of MetLife Capital, Limited Partnership’s Class A membership interest in the Gulf Wind project for a cash purchase price of approximately $ 72.8 million . As a result of the acquisitions, the Company owns 100% of the membership interests in the Gulf Wind project. The Company's additional paid-in capital was increased by $ 17.2 million , representing the difference between the aggregate purchase price and carrying values of the noncontrolling interests as of July 28, 2015. Asset Acquisition Amazon Wind Farm Fowler Ridge On April 29, 2015, the Company acquired 100% of the membership interests in Fowler Ridge IV Wind Farm LLC through the acquisition of Fowler Ridge IV B Member LLC from Pattern Development, pursuant to a Purchase and Sale Agreement, for a purchase price of approximately $37.5 million , paid at closing, in addition to $0.6 million of capitalized transaction-related expenses, and contingent payments of up to $29.1 million , payable upon tax equity funding. The 150 MW wind project, named Amazon Wind Farm Fowler Ridge, located in Benton County, Indiana, achieved commercial operation on December 4, 2015 . Following the achievement of commercial operation, the Company and certain tax equity investors made capital contributions to fund the repayment of the construction loan. As a result, the Company and the tax equity investors hold initial ownership interests of 65% and 35% , respectively, in the project’s initial distributable cash flows. The Company acquired certain assets and assumed certain liabilities of Amazon Wind Farm Fowler Ridge, including various operating contracts, deferred development costs, tangible assets, real property interests, governmental approvals and other assets. The fair value of the purchase consideration, including transaction costs of the asset acquisition, is allocated to the relative fair value of the individual assets and liabilities. The preliminary fair value of the assets acquired and liabilities assumed in connection with the Amazon Wind Farm Fowler Ridge acquisition are as follows (in thousands): April 29, 2015 Prepaid expenses and other current assets $ 1,753 Deferred financing costs, current 2,132 Turbine advances 4,000 Construction in progress 34,487 Finite-lived intangible assets, net of accumulated amortization 2,247 Accrued construction costs (6,549 ) Total consideration $ 38,070 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. During the three months ended December 31, 2015, the Company adjusted the initial valuation and increased construction in progress by $0.1 million related to the capitalization of additional transaction-related expenses, resulting in total capitalized transaction-related expenses of $0.6 million . In connection with the acquisition, the Company may make additional contingent payments of up to $29.1 million , consisting of a $25.1 million fixed amount and up to an additional $4.0 million , as calculated based on final budget to actual amounts, both of which are payable to Pattern Development upon tax equity funding. On December 18, 2015, pursuant to the Purchase and Sale Agreement between the Co

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment The following presents the categories within property, plant and equipment (in thousands): December 31, 2015 2014 Operating wind farms $ 3,700,140 $ 2,624,640 Furniture, fixtures and equipment 3,500 4,366 Land 141 141 Subtotal 3,703,781 2,629,147 Less: accumulated depreciation (409,161 ) (278,291 ) Property, plant and equipment, net $ 3,294,620 $ 2,350,856 The Company recorded depreciation expense related to property, plant and equipment of $141.2 million , $102.9 million and $82.0 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. The Company has received $253.4 million from the U.S Department of the Treasury under cash grants in lieu of investment tax credits ("Cash Grant") for its Ocotillo, Santa Isabel and Spring Valley wind farms. 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 and reduced depreciation expense in the consolidated statements of operations by approximately $11.4 million , $12.7 million and $13.0 million for the years ended December 31, 2015 , 2014 and 2013 , respectively.

Finite-Lived Intangible Assets

Finite-Lived Intangible Assets and Liability	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets and Liability	Finite-Lived Intangible Assets and Liability The following presents the major components of the finite-lived intangible assets and liability (in thousands): December 31, 2015 Weighted Average Remaining Life Gross Accumulated Amortization Net Intangible assets Power purchase agreement 14 $ 97,400 $ (4,114 ) $ 93,286 Other intangible assets 17 4,679 (243 ) $ 4,436 Total intangible assets $ 102,079 $ (4,357 ) $ 97,722 Intangible liability Power purchase agreement 17 $ (60,300 ) $ 2,168 $ (58,132 ) December 31, 2014 Weighted Average Remaining Life Gross Accumulated Amortization Net Other intangible assets 17 $ 1,411 $ (154 ) $ 1,257 The Company presents amortization of the PPA asset and PPA liability as electricity sales in the consolidated statements of operations, resulting in a decrease of $ 4.1 million and an increase of $ 2.2 million in electricity sales, respectively, for the year ended December 31, 2015 . For the years ended December 31, 2015, 2014 and 2013, the Company recorded amortization expense of $0.1 million , $0.2 million and zero , respectively, related to other intangible assets in depreciation, amortization and accretion in the consolidated statements of operations. The following table presents estimated future amortization for the next five years related to the PPA asset and PPA liability and other intangible assets: Year ended December 31, Power purchase agreements, net Other intangible assets 2016 $ 3,049 $ 277 2017 3,031 352 2018 3,031 277 2019 3,031 277 2020 3,049 277 Thereafter 19,963 2,976

Unconsolidated Investments

Unconsolidated Investments	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Unconsolidated Investments	Unconsolidated Investments The following projects are accounted for under the equity method of accounting and are presented in the Company's consolidated balance sheets for the periods below (in thousands): December 31, Percentage of Ownership December 31, 2015 2014 2015 2014 South Kent $ 6,185 $ 17,360 50.0 % 50.0 % Grand 5,735 11,719 45.0 % 45.0 % K2 104,553 — 33.3 % N/A Unconsolidated investments $ 116,473 $ 29,079 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 operation in March 2014. Grand 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 operation in December 2014. K2 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 operation in May 2015. See Note 3 , Acquisitions - Equity Method Investments , for disclosure on the acquisition of the one-third equity interest in K2. El Arrayán On June 25, 2014, the Company increased its total ownership interest in El Arrayán to 70% . See Note 3 , Acquisitions - Business Combinations - El Arrayán Acquisition , 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 and statements of operations for K2 as of December 31, 2015 and for the year ended December 31, 2015 and statements of operations for El Arrayán for the year ended December 31, 2014, prior to its consolidation in June 2014 and December 31, 2013, pursuant to Regulation S-X Rule 4-08 (g) (in thousands): December 31, 2015 Current assets $ 46,342 Non-current assets 631,151 Total assets $ 677,493 Current liabilities $ 46,901 Non-current liabilities 617,460 Total liabilities 664,361 Total equity 13,132 Total liabilities and equity $ 677,493 Year Ended December 31, 2015 2014 2013 Revenue $ 52,130 $ 1,821 $ — Cost of revenue 18,450 1,060 15 Operating expenses 3,140 682 900 Other expense 10,061 1,341 26 Net (loss) income $ 20,479 $ (1,262 ) $ (941 )

Accounts Payable and Other Accr

Accounts Payable and Other Accrued Liabilities	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Accounts Payable and Other Accrued Liabilities	Accounts Payable and Other Accrued Liabilities The following table presents the components of accounts payable and other accrued liabilities (in thousands): December 31, 2015 2014 Accounts payable $ 625 $ 673 Other accrued liabilities 9,583 7,892 Warranty settlement payments — 639 LTSA/PPE upgrades liability 4,909 680 Turbine operations and maintenance payable 985 1,310 Purchase agreement obligations 5,749 — Land lease rent payable 2,513 2,115 Spare-parts inventory payables 1,181 — Payroll liabilities 5,345 4,453 Property tax payable 11,145 4,625 Sales tax payable 741 2,406 Accounts payable and other accrued liabilities $ 42,776 $ 24,793

Revolving Credit Facility

Revolving Credit Facility	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Revolving Credit Facility	Revolving Credit Facility On November 15, 2012, certain subsidiaries of 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 subsidiaries have 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. During 2014, certain subsidiaries of the Company entered into an Amended and Restated Credit and Guaranty Agreement which increased the available borrowings under the Existing Credit Agreement from $ 145.0 million to $ 350.0 million . The maturity date was also extended to December 2018. During 2015, certain subsidiaries of the Company entered into two separate amendments to the Amended and Restated Credit and Guaranty Agreement which added two additional lenders to the facility and increased available borrowings under the Existing Credit Agreement from $ 350.0 million to $ 500.0 million ("Revolving Credit Facility"). The Revolving Credit 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 holding company subsidiaries' ability to incur debt, grant liens, sell or lease assets, transfer equity interests, dissolve, pay distributions and change its business. As of December 31, 2015, the Company's holding company subsidiaries are in compliance with covenants contained in the Revolving Credit Facility. The loans under our Revolving Credit Facility 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% (corresponding to applicable leverage ratios of the borrower). The Eurodollar rate loans accrue interest at a rate per annum equal to LIBOR, as published by Reuters plus an applicable margin ranging from 2.25% to 2.75% (corresponding to applicable leverage ratios of the borrower). Under the Revolving Credit Facility, we 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% . We also pay letter of credit fees. As of December 31, 2015 and 2014 , outstanding loan balances under the Revolving Credit Facility were $ 355.0 million and $ 50.0 million , respectively. In addition, as of December 31, 2015 and 2014 , letters of credit of $27.2 million and $45.1 million , respectively, were issued under the Revolving Credit Facility.

Long Term Debt

Long Term Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Long Term Debt	Long Term Debt The Company’s long term project debt for the following periods is presented below (in thousands): As of December 31, 2015 December 31, Contractual Interest Rate Effective Interest Rate 2015 2014 Maturity Project-level Fixed interest rate El Arrayán EKF term loan $ 107,160 $ 109,630 5.56 % 5.56 % March 2029 St. Joseph term loan — 189,472 5.88 % 5.95 % May 2031 Santa Isabel term loan 109,973 112,609 4.57 % 4.57 % September 2033 Variable interest rate Logan's Gap construction loan — 58,691 1.57 % 1.57 % December 2015 Gulf Wind term loan — 156,122 3.28 % 6.59 % (1) March 2020 Ocotillo commercial term loan (5) 208,119 222,175 2.36 % 3.77 % (1) (2) August 2020 Lost Creek term loan 110,846 — 2.19 % 6.49 % (1) September 2027 El Arrayán commercial term loan 97,418 99,665 3.17 % 5.65 % (1) March 2029 Spring Valley term loan 132,670 167,261 2.36 % 4.89 % (1) June 2030 Ocotillo development term loan 104,500 106,700 2.71 % 4.37 % (1) August 2033 St. Joseph term loan (5) 158,181 — 2.46 % 3.84 % November 2033 Imputed interest rate Hatchet Ridge financing lease obligation 214,580 228,288 1.43 % 1.43 % December 2032 1,243,447 1,450,613 Unamortized premium, net (3) 1,380 — Unamortized financing costs (26,303 ) (36,755 ) Current portion (including construction loans) (4) (44,144 ) (109,693 ) Long-term debt, less current portion (including construction loans) $ 1,174,380 $ 1,304,165 (1) Includes impact of interest rate derivatives. See Note 11 , Derivative Instruments , for discussion of interest rate derivatives. (2) In October 2014, the Ocotillo financing agreement was amended to include a margin rate decrease of 1.0% for the commercial term loan. (3) Amount is related to the Lost Creek term loan. (4) Amount is presented net of the current portion of unamortized financing costs of $ 3.7 million and $ 11.9 million as of December 31, 2015 and 2014, respectively. (5) The amortization for the Ocotillo commercial term loan and the St. Joseph term loan are through June 2030 and September 2036, respectively, which differs from the stated maturity date of such loans due to prepayment requirements. The following are principal payments, excluding deferred financing costs, due under the Company's long-term project debt as of December 31, 2015 for the following years (in thousands): Amount 2016 $ 47,613 2017 51,705 2018 60,438 2019 66,304 2020 69,526 Thereafter 947,861 Total $ 1,243,447 Interest and commitment fees incurred and interest expense for the long term debt, the revolving credit facility and convertible debt consisted of the following (in thousands): Year Ended December 31, 2015 2014 2013 Interest and commitment fees incurred $ 70,847 $ 59,864 $ 57,478 Capitalized interest, commitment fees, and letter of credit fees (6,607 ) (2,856 ) (4,210 ) Letter of credit fees incurred 4,572 4,377 3,530 Amortization of debt discount/premium, net 1,660 — — Amortization of financing costs 7,435 6,309 6,816 Interest expense $ 77,907 $ 67,694 $ 63,614 Project-level Financing Arrangements The Company typically finances its wind projects through project entity specific debt secured by each project's assets with no recourse to the Company. Typically, these financing arrangements provide for a construction loan, which upon completion may be converted into a term loan or repaid through capital contributions from the Company and tax equity investors. Collateral for project level facilities typically include each project's tangible assets and contractual rights and cash on deposit with the depository agents. Each loan agreement contains a broad range of covenants that, subject to certain exceptions, restrict each project's ability to incur debt, grant liens, sell or lease certain assets, transfer equity interests, dissolve, make distributions and change their business. As of December 31, 2015, all projects were in compliance with their financing covenants. The following is a summary of debt arrangements entered into, amended or acquired during the years ended December 31, 2015 and 2014, respectively. St. Joseph On November 17, 2015, St. Joseph extinguished its existing credit facility consisting of a term loan of approximately C$212.5 million and maturing in March 2031 and entered into a C$244.0 million credit agreement that provided a term loan facility, a letter of credit facility and an interest hedge facility (the "St. Joseph Credit Agreement") maturing in November 2033. Pursuant to the terms of the St. Joseph Credit Agreement, the prior lenders to the project were repaid in full with borrowings from a new group of lenders. The interest rate on the St. Joseph term loan was reduced from a fixed rate of 5.95% to a Canadian Dollar Offered Rate (CDOR) plus 1.625% (increasing by 0.125% every three years ). The size of the St. Joseph Credit Agreement was increased to C$219.0 million to include finance fees and costs associated with the new arrangement. The St. Joseph Credit Agreement also established approximately C$25.0 million in new letter of credit facilities for the project to support various reserve requirements and security obligations under the power purchase agreement. In connection with the St. Joseph Credit Agreement, St. Joseph entered into interest rate swaps with each of the new lenders to manage exposure to interest rate risk. The interest rate swaps were designed to effectively set 90% of the St. Joseph Credit Agreement interest rate at 4.0% (increasing by 0.125% every three years ). See Note 11 , Derivative Instruments , for additional information. As a result of the repayment of the existing term loan of approximately C$212.5 million , the Company recognized a loss on debt extinguishment of approximately $0.8 million , which includes unamortized deferred financing costs and legal fees incurred as a result of the extinguishment, for the year ended December 31, 2015. Spring Valley On October 20, 2015, Spring Valley entered into an amendment to its financing agreement with existing lenders. Pursuant to the terms of the refinancing, the interest rate on the term loan for the facility was reduced from LIBOR plus 2.38% (increasing 0.25% every four years ) to LIBOR plus 1.75% (increasing by 0.125% every four years ). Through proceeds from the Revolving Credit Facility, the Company also made a prepayment of $29.7 million towards the outstanding principal balance on Spring Valley's term loan facility which reduced the outstanding balance of the term loan to approximately $133.2 million . In connection with the prepayment of $29.7 million , the Company discontinued the cash flow hedge designation on a portion of the interest rate swap associated with the original outstanding principal balance prior to prepayment. See Note 11 , Derivative Instruments , for additional information. The Company accounted for the Spring Valley refinancing event as a debt modification for all lenders. In accordance with ASC 470-50, Debt Modifications and Extinguishments , the amendment fees of $0.9 million and the remaining $5.0 million of unamortized debt issuance costs related to the original debt will be amortized over the remaining term of the modified debt using the effective interest method. 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 . On September 18, 2015, the Company and certain tax equity investors made capital contributions to fund the repayment of the Logan's Gap construction loan. As of December 31, 2015, the balance of the construction loan was zero . See Note 15 , Stockholders' Equity - Noncontrolling Interests , for additional information. Lost Creek On September 3, 2015, Lost Creek entered into a Second Amended and Restated Credit Agreement ("Lost Creek Term Loan")which, among other things, reduced the interest rate from LIBOR plus 2.75% (with periodic increases of 0.25% ) to LIBOR plus 1.65% (increasing by 0.125% every four years ) and extended the maturity of the Lost Creek Term Loan from March 2021 to September 2027. Under ASC 470-50, Debt Modifications and Extinguishments , these amendments to the Lost Creek Term Loan are considered a modification of debt on a lender-by-lender basis. As a result, the capitalized amendment fees of $1.5 million paid to lenders are amortized over the remaining term of the modified debt using the effective interest method. In addition, the Company expensed third party legal and other fees of approximately $0.7 million , which are included in other (expense) income, net in the Company's consolidated statements of operations. The Lost Creek Term Loan includes a collateral agreement that requires proceeds from the sale of energy from the Lost Creek wind project be remitted directly to the depositary agent of the Lost Creek Term Loan to provide for debt service payments and operating costs required under the Lost Creek Term Loan. The Lost Creek Term Loan also replaced the existing debt service and operating and maintenance reserves with a $10.7 million revolving credit facility provided by certain lenders in the event Lost Creek is unable to make payments towards debt service reserve requirements and operating and maintenance reserve requirements. The Lost Creek Term Loan is subject to certain covenants, including limitations on additional indebtedness, limitations on liens, requirements for periodic financial and operational information, and compliance with certain required financial ratios. The Lost Creek Term Loan also contains voluntary prepayment provisions which provide for the right to prepay the Lost Creek Term Loan without premium or penalty and contains mandatory prepayments for such events as upwind array events. As of December 31, 2015, there has been no requirement to make any such mandatory prepayments of amounts borrowed under the term loan. Additionally, the Lost Creek Term Loan restricts payment of dividends, distributions, and returns of capital to affiliates of Lost Creek unless provided by the Lost Creek Term Loan. Gulf Wind On July 28, 2015, the Company acquired the noncontrolling interests in the Gulf Wind project, resulting in a 100% ownership of the membership interests in the Gulf Wind project. See Note 15 , Stockholders' Equity - Noncontrolling Interests , for additional information. Subsequent to the acquisitions, on July 30, 2015, the Company prepaid 100% of the outstanding balance of the Gulf Wind project’s term loan of $154.1 million , resulting in a loss on extinguishment of debt, primarily related to the write-off of deferred financing costs, of approximately $4.1 million . As a result of the early extinguishment of debt, the Company terminated the related interest rate swaps and cap. See Note 11 , Derivative Instruments , for additional information. Amazon Wind Farm Fowler Ridge On April 29, 2015, Amazon Wind Farm Fowler Ridge entered into a $199.1 million construction loan facility and $22.5 million of letter of credit facilities, as required by the PPA and renewable energy credit agreement. The interest rate on the construction loan facility was 1.69% . Under the financing agreement, the construction loan facility will be repaid at the earlier of commercial operation or February 29, 2016, the scheduled maturity date, through capital contributions from both the tax equity investors and the Company. The Company also entered into a Letter of Credit, Reimbursement and Loan Agreement pursuant to which the $11.2 million REC letter of credit facility expires on April 29, 2016 and the $11.3 million PPA letter of credit facility expires on April 29, 2020. On December 18, 2015, the Company and certain tax equity investors made capital contributions to fund the repayment of the Amazon Wind Farm Fowler Ridge construction loan facility. As of December 31, 2015, the balance of the construction loan facility was zero . See Note 15 , Stockholders' Equity - Noncontrolling Interests , for additional information. 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 letters of credit facilities totaling 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. Financing Lease Obligations In December 2010, Hatchet Ridge entered into a sale-leaseback agreement to finance the project facility for 22 years . The Company evaluated the agreement in accordance with ASC 840, Leases , and ASC 360, Property Plant and Equipment, and determined that due to continuing involvement with the project facility, the Company is precluded from treating the agreement as a sale-lease back transaction and accounts for the agreement as a financing lease obligation. Collateral for the agreement 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. Payments under the financing lease for the years ended December 31, 2015, 2014 and 2013, were $16.9 million , $15.0 million and $14.8 million , respectively. Convertible Senior Notes due 2020 In July 2015, the Company issued $225.0 million aggregate principal amount of 4.00% convertible senior notes due 2020 ("2020 Notes"). The 2020 Notes bear interest at a rate of 4.00% per year, payable semiannually in arrears on January 15 and July 15 of each year, beginning on January 15, 2016. The 2020 Notes will mature on July 15, 2020. The 2020 Notes were sold in a private placement. At any time prior to the close of business on the business day immediately preceding January 15, 2020, holders may convert the 2020 Notes under the following circumstances: • during any calendar quarter commencing after the calendar quarter ending on September 30, 2015, if the last reported sale price of the Company’s Class A common stock for at least 20 trading days during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; • during the five business day period after any 10 consecutive trading day period (the "measurement period") in which the trading price per $1,000 principal amount of notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Class A common stock and the conversion rate on each such trading day; • upon occurrence of specified corporate events; or • at any time on or after January 15, 2020 until close of business on the second scheduled trading day immediately preceding the maturity date. Upon conversion, the Company may, at its discretion, pay cash, shares of the Company’s Class A common stock, or a combination of cash and stock. The 2020 Notes will be converted at an initial conversation rate of 35.4925 shares of Class A common stock per $1,000 principal amount of 2020 Notes, which is equivalent to an initial conversion price of approximately $28.175 per share of Class A common stock. The conversion rate is subject to adjustment in some events (including, but not limited to, certain cash dividends made to holders of the Company's Class A common stock which exceed the initial dividend threshold of $0.363 per quarter per share). The conversion rate would be adjusted to offset the effect of the portion of the dividend in excess of $0.363 . The conversion rate will not be adjusted for any accrued and unpaid interest. The 2020 Notes are not redeemable prior to maturity. Upon the occurrence of certain fundamental changes involving the Company, holders of the 2020 Notes may require the Company to repurchase all or a portion of their 2020 Notes for cash at a price of 100% of the principal amount of the 2020 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. The 2020 Notes are guaranteed on a senior unsecured basis by a subsidiary of the Company and are general unsecured obligations of the Company. The obligations rank senior in rights of payment to the Company’s subordinated debt, equal in right of payment to the Company’s unsubordinated debt and effectively junior in right of payment to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness. The 2020 Notes are accounted for in accordance with ASC 470-20, Debt with Conversion and Other Options , and ASC 815, Derivatives and Hedging. Under ASC 815 , issuers of certain convertible debt instruments are generally required to separately account for the conversion option of the convertible debt instrument as a derivative, unless it meets a scope exception which allows the issuer to classify the conversion option as equity. As the 2020 Notes have met the scope exception, the Company is required to separately account for the liability and equity components of the convertible debt instrument in accordance with ASC 470-20, Debt with Conversion and Other Options . The carrying amount of the liability component is determined based on the fair value of a similar liability without the conversion option. The market interest rate used in determining the liability component of the 2020 Notes was 6.6% . The amount of the equity component is then calculated by deducting the fair value of the liability component from the principal amount of the 2020 Notes. The following table presents a summary of the equity and liability components of the 2020 Notes (in thousands): December 31, 2015 Principal $ 225,000 Less: Unamortized debt discount (22,624 ) Unamortized financing costs (5,014 ) Carrying value of convertible senior notes $ 197,362 Carrying value of the equity component (1) $ 23,743 (1) Included in the consolidated balance sheets as additional paid-in capital, net of $0.7 million in equity issuance costs. During the year ended December 31, 2015, in relation to the 2020 Notes, the Company recorded $3.8 million , $0.5 million and $1.8 million related to the contractual coupon interest, amortization of financing costs and amortization of debt discount, respectively, in interest expense in its consolidated statements of operations.

Asset Retirement Obligation

Asset Retirement Obligation	12 Months Ended
	Dec. 31, 2015
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	Asset Retirement Obligation The Company’s asset retirement obligations represent the estimated cost of decommissioning the turbines, removing above-ground installations and restoring the sites at the end of its estimated economic useful life. Effective January 1, 2015, the Company changed its estimate of the useful lives of wind farms for which construction began after 2011, from 20 years to 25 years. As a result, during the year ended December 31, 2015 , the Company recorded a one-time adjustment of $1.9 million to reduce the carrying balance of the asset retirement obligations to reflect the change estimated useful life of the underlying wind farms and related estimate associated with the timing of the original undiscounted cash flows. The following table presents a reconciliation of the beginning and ending aggregate carrying amounts of asset retirement obligation (in thousands): December 31, 2015 2014 Beginning asset retirement obligations $ 29,272 $ 20,834 Net additions during the year 13,189 7,195 Foreign currency translation adjustment (411 ) (228 ) Adjustment related to change in useful life (1,907 ) — Accretion expense 2,054 1,471 Ending asset retirement obligations $ 42,197 $ 29,272

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments The Company employs a variety of derivative instruments to manage its exposure to fluctuations in electricity prices, interest rates and foreign currency exchange rates. Energy prices are subject to wide swings as supply and demand are impacted by, among many other unpredictable items, weather, market liquidity, generating facility availability, customer usage, storage, and transmission and transportation constraints. Interest rate risk exists primarily on variable-rate debt for which the cash flows vary based upon movement in market prices. Additionally, the Company is exposed to foreign currency exchange rate risk primarily from its business operations in Canada and Chile. The Company’s objectives for holding these derivative instruments include reducing, eliminating and efficiently managing the economic impact of these exposures as effectively as possible. We do not hedge all of our electricity price risk, interest rate risks, and foreign currency exchange rate risks, thereby exposing the unhedged portions to changes in market prices. As of December 31, 2015, the Company had other energy-related contracts that did not meet the definition of a derivative instrument or qualified for the NPNS exception and were therefore exempt from fair value accounting treatment. The following tables present the fair values of the Company's derivative instruments on a gross basis as reflected on the Company’s consolidated balance sheets (in thousands): December 31, 2015 Derivative Assets Derivative Liabilities Current Long-Term Current Long-Term Fair Value of Designated Derivatives: Interest rate swaps $ — $ — $ 10,034 $ 24,360 Fair Value of Undesignated Derivatives: Interest rate swaps $ — $ 559 $ 4,309 $ 4,299 Energy derivative 20,856 42,827 — — Foreign currency forward contracts 3,482 628 — — Total Fair Value $ 24,338 $ 44,014 $ 14,343 $ 28,659 December 31, 2014 Derivative Assets Derivative Liabilities Current Long-Term Current Long-Term Fair Value of Designated Derivatives: Interest rate swaps $ — $ 525 $ 12,904 $ 17,467 Fair Value of Undesignated Derivatives: Interest rate swaps $ — $ 2,523 $ 3,403 $ — Interest rate cap — 352 — — Energy derivative 18,506 45,969 — — Total Fair Value $ 18,506 $ 49,369 $ 16,307 $ 17,467 The following table summarizes the notional amounts of the Company's outstanding derivative instruments (in thousands except for MWh): December 31, Unit of Measure 2015 2014 Designated Derivative Instruments Interest rate swaps USD $ 379,808 $ 440,467 Interest rate swaps CAD $ 196,988 $ — Undesignated Derivative Instruments Interest rate swaps USD $ 275,424 $ 272,716 Interest rate cap USD $ — $ 42,102 Energy derivative MWh 1,707,350 2,211,563 Foreign currency forward contracts CAD $ 62,300 $ — Derivatives Designated as Hedging Instruments Cash Flow Hedges The Company has interest rate swap agreements to hedge variable rate project-level debt. Under these interest rate swaps, the projects make fixed-rate interest payments and the counterparties to the agreements make variable-rate interest payments. For interest swaps that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative is reported as a component of accumulated other comprehensive loss and reclassified into earnings in the period or periods during which a cash settlement occurs. The designated interest rate swaps have remaining maturities ranging from approximately 11.8 years to 20.8 years . The following table presents gains and losses on derivative contracts designated and qualifying as cash flow hedges recognized in accumulated other comprehensive loss, as well as amounts reclassified to earnings for the following periods (in thousands): Year Ended December 31, Description 2015 2014 2013 Gains (losses) recognized in accumulated OCI Effective portion of change in fair value $ (16,163 ) $ (33,444 ) $ 24,932 Gains (losses) reclassified from accumulated OCI into: Interest expense Derivative settlements $ 12,234 $ 13,774 $ 11,943 Realized loss on designated derivatives, net Termination of derivatives $ 11,221 $ — $ — Loss (gain) on undesignated derivatives, net De-designation of derivatives $ 5,918 $ — $ — Gains (losses) recognized in interest expense Ineffective portion $ (809 ) $ — $ — The Company estimates that $10.0 million in accumulated other comprehensive loss will be reclassified into earnings over the next twelve months. Spring Valley On October 20, 2015, in connection with the amendment to Spring Valley's term loan, the Company made a prepayment of $29.7 million towards the outstanding principal balance on Spring Valley's term loan which reduced the balance to approximately $133.2 million . See Note 9, Long Term Debt - Spring Valley , for additional information. As a result, the Company discontinued the cash flow hedge designation on a portion of the interest rate swaps associated with the original outstanding principal balance prior to prepayment and reclassified approximately $5.9 million from accumulated other comprehensive loss to loss (gain) on undesignated derivatives in the Company's consolidated statements of operations. Gulf Wind On July 28, 2015, in connection with the early extinguishment of Gulf Wind's term loan, the Company terminated the related interest rate swaps which resulted in the reclassification of $11.2 million in accumulated other comprehensive loss to realized loss on designated derivatives, net in the consolidated statements of operations. Derivatives Not Designated as Hedging Instruments The following table presents gains and losses on derivatives not designated as hedges (in thousands): Year Ended December 31, Derivative Type Financial Statement Line Item Description 2015 2014 2013 Interest rate derivatives (Loss) gain on undesignated derivatives, net Change in fair value, net of settlements $ (5,758 ) (1) $ (11,668 ) $ 15,601 Interest rate derivatives (Loss) gain on undesignated derivatives, net Derivative settlements $ (4,838 ) $ (4,075 ) $ (2,099 ) Energy derivative Electricity sales Change in fair value, net of settlements $ (792 ) $ (3,878 ) $ (11,272 ) Energy derivative Electricity sales Derivative settlements $ 20,568 $ 13,525 $ 16,798 Foreign currency forward contracts (Loss) gain on undesignated derivatives, net Change in fair value, net of settlements $ 4,110 $ — $ — Foreign currency forward contracts (Loss) gain on undesignated derivatives, net Derivative settlements $ 996 $ — $ — (1) Amount includes the reclassification of $5.9 million from accumulated other comprehensive loss related to the dedesignation of certain interest rate derivative instruments at Spring Valley. Interest Rate Derivatives Interest Rate Swaps The Company has interest rate swap agreements to hedge variable rate project-level debt. Under these interest rate swaps, the projects make fixed-rate interest payments and the counterparties to the agreements make variable-rate interest payments. For interest rate swaps that are not designated and do not qualify as cash flow hedges, the changes in fair value are recorded in (loss) gain on undesignated derivatives, net in the consolidated statements of operations as these hedges are not accounted for under hedge accounting. The undesignated interest rate swaps have remaining maturities ranging from approximately 5.3 years to 14.5 years . Interest Rate Cap In 2010, Gulf Wind entered into an interest rate cap to manage its exposure to future interest rates when its long-term debt was expected to be refinanced at the end of the ten -year term. The cap provided Gulf Wind the right to receive payments and protected the Company if future interest rates exceeded approximately 6.0% . On July 28, 2015, in connection with the early extinguishment of Gulf Wind's term loan, the Company terminated the related interest rate cap which resulted in a net loss of $ 0.2 million , recognized in (loss) gain on undesignated derivatives, net in the consolidated statements of operations and primarily represents a realization of losses previously recorded within accumulated other comprehensive loss. Energy Derivative In 2010, Gulf Wind acquired an energy derivative instrument to manage its exposure to variable electricity prices over the life of the arrangement. The energy price swap fixes the price for a predetermined volume of production (the notional volume) over the life of the swap contract, through April 2019 , by locking in a fixed price per MWh. The notional volume agreed to by the parties is approximately 504,220 MWh per year. The energy derivative instrument does not meet the criteria required to adopt hedge accounting. As a result, changes in fair value are recorded in electricity sales in the consolidated statements of operations. Foreign Currency Forward Contracts In January 2015, the Company established a currency risk management program. The objective of the program is to mitigate the foreign exchange rate risk arising from transactions or cash flows that have a direct or underlying exposure in non-U.S. dollar denominated currencies in order to reduce volatility in the Company’s cash flow, which may have an adverse impact to our short-term liquidity or financial condition. A majority of the Company’s power sale agreements and operating expenditures are transacted in U.S. dollars, with a growing portion transacted in currencies other than the U.S. dollar, primarily the Canadian dollar. In 2015, the Company entered into foreign currency forward contracts at various times to mitigate the currency exchange rate risk on Canadian dollar denominated cash flows. These instruments have remaining maturities ranging from one to eighteen months. The foreign currency forward contracts are considered non-designated derivative instruments and are not used for trading or speculative purposes. As a result, changes in fair value and settlements are recorded in (loss) gain on undesignated derivatives, net in the consolidated statements of operations.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss The following table summarizes changes in the accumulated other comprehensive loss balance, net of tax, by component: Foreign Currency Effective Portion of Change in Fair Value of Derivatives Proportionate Share of Equity Investee's OCI Total Balances at December 31, 2012 $ (154 ) $ (43,877 ) $ (1,475 ) $ (45,506 ) Other comprehensive (loss) income before reclassifications (8,309 ) 24,932 2,473 19,096 Amounts reclassified from accumulated other comprehensive loss — 11,943 — 11,943 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 ) Other comprehensive loss before reclassifications (10,875 ) (33,444 ) (5,991 ) (50,310 ) Amounts reclassified from accumulated other comprehensive loss — 13,774 — 13,774 Net current period other comprehensive loss (10,875 ) (19,670 ) (5,991 ) (36,536 ) Balances at December 31, 2014 $ (19,338 ) $ (26,672 ) $ (7,903 ) $ (53,913 ) Other comprehensive loss before reclassifications (28,947 ) (16,163 ) (6,640 ) (51,750 ) Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives — 17,139 — 17,139 Amounts reclassified from accumulated other comprehensive loss — 12,234 2,412 14,646 Net current period other comprehensive (loss) income (28,947 ) 13,210 (4,228 ) (19,965 ) Balances at December 31, 2015 $ (48,285 ) $ (13,462 ) $ (12,131 ) $ (73,878 ) Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015 — (553 ) — (553 ) Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015 $ (48,285 ) $ (12,909 ) $ (12,131 ) $ (73,325 )

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	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 set forth below. Transfers between levels are recognized at the end of each quarter. The Company did not recognize any transfers between levels during the periods presented. 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 and cash equivalents, restricted cash, trade receivables, current portion of prepaid expenses, related party receivable/payable, reimbursable interconnection costs, accounts payable and other accrued liabilities, accrued construction costs, accrued interest, dividends payable and the revolving credit facility. Based on the nature and short maturity of these instruments, their carrying cost approximates their fair value, and they are presented in the Company’s financial statements at carrying cost. The fair values of cash and cash equivalents and restricted cash are classified as Level 1 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): December 31, 2015 Level 1 Level 2 Level 3 Total Assets Interest rate swaps $ — $ 559 $ — $ 559 Energy derivative — — 63,683 63,683 Foreign currency forward contracts — 4,110 — 4,110 $ — $ 4,669 $ 63,683 $ 68,352 Liabilities Interest rate swaps $ — $ 43,002 $ — $ 43,002 Energy derivative — — — — Foreign currency forward contracts — — — — $ — $ 43,002 $ — $ 43,002 December 31, 2014 Level 1 Level 2 Level 3 Total Assets Interest rate swaps $ — $ 3,048 $ — $ 3,048 Interest rate cap — 352 — 352 Energy derivative — — 64,475 64,475 $ — $ 3,400 $ 64,475 $ 67,875 Liabilities Interest rate swaps $ — $ 33,774 $ — $ 33,774 $ — $ 33,774 $ — $ 33,774 Level 2 Inputs Derivative instruments subject to re-measurement are presented in the financial statements at fair value. The Company's 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. The Company’s foreign currency forward contracts were valued using the income approach based on the present value of the forward rates less the contract rates, multiplied by the notional amounts. Level 3 Inputs The fair value of the energy derivative instrument is determined based on a third-party valuation model. The methodology and inputs are evaluated by management for consistency and reasonableness by comparing inputs used by the third-party valuation provider to another third-party pricing service for identical or similar instruments and also agreeing inputs used in the third-party valuation model to the derivative contract for accuracy. Any significant changes are further evaluated for reasonableness by obtaining additional documentation from the third-party valuation provider. The energy derivative instrument is valued by discounting the projected net cash flows over the remaining life of the derivative instrument using forward electricity prices which are derived from observable prices, such as forward gas curves, adjusted by a non-observable heat rate for when the contract term extends beyond a period for which market data is available. The significant unobservable input in calculating the fair value of the energy derivative instrument is forward electricity 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 the energy derivative contract measured at fair value on a recurring basis using significant unobservable inputs (in thousands): 2015 2014 Balance at beginning of year $ 64,475 $ 68,353 Total gains (losses) included in electricity sales 19,776 9,646 Settlements (20,568 ) (13,524 ) Balance at end of year $ 63,683 $ 64,475 During the years ended December 31, 2015 , 2014 and 2013, the Company recognized unrealized losses on the energy derivative of $0.8 million , $3.9 million , and $11.3 million , respectively. The valuation techniques and significant unobservable inputs used in recurring Level 3 fair value measurements were as follows (in thousands, for fair value): December 31, 2015 Fair Value Valuation Technique Significant Unobservable Inputs Range Energy derivative $63,683 Discounted cash flow Forward electricity prices $12.48 - $74.94 (1) Discount rate 0.61% - 1.46% December 31, 2014 Fair Value Valuation Technique Significant Unobservable Inputs Range Energy derivative $64,475 Discounted cash flow Forward electricity prices $14.24 - $106.11 (1) Discount rate 0.26% - 1.63% (1) Represents price per MWh Financial Instruments not Measured at Fair Value The following table presents the carrying amount and fair value 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, 2015 and 2014 , but for which fair value is disclosed (in thousands): Fair Value As reflected on the balance sheet Level 1 Level 2 Level 3 Total December 31, 2015 Convertible senior notes $ 197,362 $ — $ 189,863 $ — $ 189,863 Long-term debt, including current portion $ 1,218,524 $ — $ 1,192,286 $ — $ 1,192,286 December 31, 2014 Long-term debt, including current portion $ 1,413,858 $ — $ 1,416,744 $ — $ 1,416,744 Long term debt and the convertible senior notes are presented on the consolidated balance sheets, net of financing costs. 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, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following table presents significant components of the provision for income taxes (in thousands): Year ended December 31, 2015 2014 2013 Current: Federal $ — $ — $ — State — — — Foreign 489 182 — Total current expense 489 182 — Deferred: Federal — — 2,961 State — — — Foreign 4,454 2,954 1,585 Total deferred expense 4,454 2,954 4,546 Total provision for income taxes $ 4,943 $ 3,136 $ 4,546 The following table presents the domestic and foreign components of net (loss) income before income tax provision (in thousands): Year ended December 31, 2015 2014 2013 U.S. $ (66,883 ) $ (34,788 ) $ 4,022 Foreign 16,219 (2,075 ) 10,596 Total $ (50,664 ) $ (36,863 ) $ 14,618 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 following periods: Year ended December 31, 2015 2014 2013 Computed tax at statutory rate 35.0 % 35.0 % 35.0 % Adjustment for income in non-taxable entities allocable to noncontrolling interest (13.0 )% (7.6 )% 16.5 % Foreign rate differential Tax rate differential on pre-tax book income, other (6.6 )% 5.6 % 2.1 % Local tax on branch profits/(losses)—Puerto Rico 0.3 % 1.6 % 13.1 % Permanent book/tax differences (domestic only) (0.1 )% (0.1 )% (2.2 )% Valuation allowance (25.1 )% (33.4 )% 187.2 % Chilean shareholder benefit due to tax regime change 0.4 % (3.6 )% — % Change in tax rate due to change in Chilean tax regime — % (6.2 )% — % Other (0.7 )% 0.1 % 3.1 % ARRA Section 1603 grant-basis reduction deferred tax assets — % — % (223.7 )% Effective income tax rate (9.8 )% (8.6 )% 31.1 % The following table presents significant components of the Company’s deferred tax assets and deferred tax liabilities as follows (in thousands): Year ended December 31, 2015 2014 Deferred tax assets / (liabilities) — current: Accruals, prepaids and other deferred tax assets and liabilities $ — $ (344 ) Basis difference in derivatives — 4,779 Total gross deferred tax assets / (liabilities) — current — 4,435 Less: valuation allowance — (4,266 ) Total net deferred tax assets / (liabilities) — current $ — $ 169 Deferred tax assets/(liabilities) — non-current: (1) Accruals, prepaids and other deferred tax assets and liabilities $ 1,525 $ — Basis difference in derivatives 3,187 — Property, plant and equipment (175,527 ) (104,767 ) Basis difference in foreign subsidiaries 104 37,626 Partnership interest 34,664 994 Hatchet Ridge financing 27,096 28,044 Asset retirement obligation 4,970 5,216 Unrealized loss on derivatives 305 — Other temporary differences — 256 Other deferred tax assets and liabilities (7,125 ) (5,081 ) Net operating loss carryforwards 224,194 130,248 Tax credits 4,421 — Total gross deferred tax assets/(liabilities) — non-current (1) $ 117,814 $ 92,536 Less: valuation allowance (133,193 ) (107,480 ) Total net deferred tax assets / (liabilities) — non-current (1) $ (15,379 ) $ (14,944 ) Total net deferred tax assets/(liabilities ) (1) $ (15,379 ) $ (14,775 ) (1) Presented in accordance with prospective adoption of ASU 2015-17, "Income Taxes: Balance Sheet Classification of Deferred Taxes." See Note 2 , Summary of Significant Accounting Policies - Recently Issued Accounting Standards , for additional information. 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, 2015 and 2014 are attributed primarily to the Company’s Canadian, Puerto Rican and Chilean entities. The net change in valuation allowance increased by $21.4 million and $11.8 million during the years ended December 31, 2015 and 2014 , respectively. As of December 31, 2015 , the Company had U.S federal and state net operating loss ("NOLs") carryforwards in the amount of $503.6 million and $66.0 million , respectively, which begin to expire in the year ending December 31, 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 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. NOLs prior to October 2, 2013 except for NOLs 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. 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, 2015 , 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, 2015 . 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 to 2015 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 expenses or penalties associated with unrecognized tax benefits for the years ended December 31, 2015 , 2014 and 2013 . The Company operates under a tax holiday in Puerto Rico which enacted a special tax rate of 4% for businesses dedicated to the production of energy for consumption through the use of renewal sources. Act 73 of May 28, 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 $0.4 million for 2015 . The impact of the tax holiday on basic and diluted net income (loss) per Class A common share was $0.005 .

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Initial Public Offering and Contribution Transactions On October 2, 2013, the Company issued 16,000,000 shares of Class A common stock in an initial public offering generating net proceeds of approximately $317.0 million . Concurrent with the initial public offering, the Company 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 initial public offering as additional consideration to Pattern Development for certain entities and assets contributed to the Company ("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 initial public offering. In accordance with ASC 805-50-30-5, Transactions between Entities under Common Control , the Company 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, the Company’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, the Company, 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. In July 2015, the Company acquired the noncontrolling interests of Gulf Wind. Refer to the Noncontrolling Interests discussion below, for additional information. 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, 2015 and 2014 , there was no preferred stock issued and outstanding. Common Stock On July 28, 2015, the Company completed an underwritten public offering of its Class A common stock. In total, 5,435,000 shares of the Company's Class A common stock were sold. Net proceeds generated for the Company were approximately $120.8 million after deduction of underwriting discounts, commissions and transaction expenses. 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 Class A common stock. The Company received net proceeds of approximately $196.2 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. On May 14, 2014, the Company completed an underwritten public offering of its Class A common stock resulting in a reduction of Pattern Development’s interest in the Company 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 transactions with Pattern Development after May 14, 2014 are recognized at fair value on the measurement date in accordance with the ASC 805, Business Combinations . On February 9, 2015, the Company completed an underwritten public offering of its Class A common stock, resulting in a further reduction of Pattern Development’s interest in the Company from 35% to 25% causing it to no longer be entitled to certain approval rights pursuant to the Shareholder Approval Rights Agreement dated October 2, 2013. Below is a summary of the rights and preferences of the Company’s Class A common stock as of December 31, 2015 and also the Company's Class B common stock as of December 31, 2014 . The Company’s Class B common stock converted on a one-to-one basis into Class A common stock on December 31, 2014. As a result, the shares of Class B common stock were retired and the Company is no longer authorized to issue shares of Class B common stock. Voting Rights Holders of the Company’s Class A 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. On February 9, 2015, Pattern Development's interest in the Company was reduced to 25% causing it to no longer be eligible to certain approval rights pursuant to Shareholder Approval Rights Agreement. 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. Dividends Per Share Declaration Date Record Date Payment Date 2015: Fourth Quarter $ 0.3720 October 29, 2015 December 31, 2015 January 29, 2016 Third Quarter $ 0.3630 July 21, 2015 September 30, 2015 October 30, 2015 Second Quarter $ 0.3520 April 20, 2015 June 30, 2015 July 30, 2015 First Quarter $ 0.3420 February 24, 2015 March 31, 2015 April 30, 2015 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. Conversion Upon the later of December 31, 2014 and the date on which the South Kent project achieves commercial operation ("Conversion Event"), all of the outstanding Class B common stock automatically converted, on a one-for-one basis, into Class A shares. There were no other conversion rights attached to Class B common stock. The Company’s South Kent project achieved commercial operation 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 operation 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 represented the intrinsic value of the conversion feature, which was 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 was convertible, as of October 2, 2013, which was the date of the Company’s initial public offering. The beneficial conversion feature was 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 were no available retained earnings. Noncontrolling Interests The following table presents the balances for noncontrolling interests by project and the Company's respective ownership percentage (in thousands, except percentages). See Note 3, Acquisitions , for additional information. Noncontrolling Ownership Percentage December 31, December 31, 2015 2014 2015 2014 Gulf Wind $ — $ 97,061 — % 60 % El Arrayán 34,224 35,624 30 % 30 % Logan's Gap 190,397 — 18 % N/A Panhandle 1 195,791 205,333 21 % 21 % Panhandle 2 184,773 192,568 19 % 19 % Post Rock 196,346 — 40 % N/A Amazon Wind Farm Fowler Ridge 142,731 — 35 % N/A Noncontrolling interest $ 944,262 $ 530,586 The following table presents the components of total noncontrolling interest as reported in stockholders’ equity in the consolidated balance sheets by project (in thousands). See Note 3, Acquisitions , for additional information. Capital Accumulated Income (Loss) Accumulated Other Comprehensive Loss Noncontrolling Interest Balances at December 31, 2013 $ 90,217 $ 18,601 $ (9,024 ) $ 99,794 Contribution from noncontrolling interests 406,163 — — 406,163 Fair value of noncontrolling interest in El Arrayán 35,259 — — 35,259 Distribution to noncontrolling interests (2,100 ) — — (2,100 ) Net loss — (8,709 ) — (8,709 ) Other comprehensive income, net of tax — — 179 179 Balances at December 31, 2014 529,539 9,892 (8,845 ) 530,586 Acquisition of Post Rock 205,100 — — 205,100 Buyout of noncontrolling interests (88,747 ) (14,244 ) 7,944 (95,047 ) Contributions from noncontrolling interests 334,231 — — 334,231 Distributions to noncontrolling interests (7,882 ) — — (7,882 ) Net loss — (23,074 ) — (23,074 ) Other comprehensive income, net of tax — — 348 348 Balances at December 31, 2015 $ 972,241 $ (27,426 ) $ (553 ) $ 944,262

Equity Incentive Award Plan

Equity Incentive Award Plan	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Incentive Award Plan	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 ("RSUs") to employees, directors and consultants. RSAs provide the holder with immediate voting rights, but are restricted in all other respects until released. RSUs generally entitle the holders the right to receive the underlying shares of the Company's common stock upon vesting. Upon cessation of services to the Company, any nonvested RSAs and RSUs will be canceled. All nonvested RSAs and RSUs accrue dividends and distributions, which are subject to vesting and paid in cash upon release. Accrued dividends and distributions are forfeitable to the extent that the underlying awards do not vest. During 2015, the Company granted 186,136 RSAs to certain employees and 22,772 RSUs to certain directors. As of December 31, 2015 , 2,083,734 aggregate number of Class A shares were available for issuance under the 2013 Plan. Stock-Based Compensation Stock-based compensation expenses related to stock options, RSAs, and RSUs are recorded as a component of general and administrative expenses in the Company’s consolidated statements of operations and totaled $4.5 million , $4.1 million and $0.5 million for the years ended December 31, 2015 , 2014 and 2013, respectively. Stock Options The Company did not grant stock option awards under the 2013 Plan during the years ended December 31, 2015 and 2014. For the year ended December 31, 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 Risk-free interest rate 1.68% Expected life (in years) 5.8 Expected volatility 36% Expected dividend yield 5.7% The following table summarizes stock option activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Exercise Price Weighted Average Remaining Contractual Life Aggregate Intrinsic Value Outstanding at December 31, 2014 429,962 $ 22.00 Exercised — 22.00 Forfeited or expired — 22.00 Outstanding at December 31, 2015 429,962 $ 22.00 7.8 $ — (1) Exercisable at December 31, 2015 318,670 $ 22.00 7.8 $ — (1) Vested and expected to vest, net of estimated forfeitures at December 31, 2015 429,962 $ 22.00 7.8 $ — (1) (1) Closing stock price on December 31, 2015 is lower than the stock option exercise price. The weighted-average grant-date fair value per stock option granted during the year ended December 31, 2013 was $4.11 . During the year ended December 31, 2014, the Company issued 14,861 shares as a result of employee stock option exercises and cash received on exercise was $0.3 million . The total intrinsic value of stock options exercised was $0.1 million for the year ended December 31, 2014 . Intrinsic value is defined as the amount by which the fair value of the underlying stock exceeds the exercise price at the time of stock option exercise. No stock options were exercised during each of the years ended December 31, 2015 and 2013. As of December 31, 2015 , the total unrecorded stock-based compensation expense, net of estimated forfeitures, related to nonvested stock options was $0.5 million , which is expected to be amortized over a weighted-average period of 0.8 years. Restricted Stock Awards The Company measures the fair value of time-based 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 RSA activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Grant-Date Nonvested at December 31, 2014 118,015 $ 25.29 Granted 100,868 $ 29.58 Vested (65,189) $ 26.23 Forfeited — N/A Repurchased for employee tax withholding (30,826) $ 27.67 Nonvested at December 31, 2015 122,868 $ 27.71 For the years ended December 31, 2015 , 2014 and 2013 , the total fair value of RSAs vested was $1.7 million , $2.2 million and $0.2 million , respectively. The weighted-average grant date fair values per RSA granted during the same periods were $29.58 , $27.63 and $22.71 , respectively. As of December 31, 2015 , the total unrecorded stock-based compensation expense for nonvested RSAs was $3.3 million , which is expected to be amortized over a weighted-average period of 1.5 years . RSAs that contain Market Conditions On April 10, 2015, the Company granted 85,268 restricted stock awards ("TSR-RSAs") to certain senior management personnel. These TSR-RSAs vest between 0% and 150% of the "Target" ( 56,844 ) at the later of a three -year performance period (January 1, 2015 - December 31, 2017), or the end of the requisite service period, which shall be no later than March 15, 2018, in accordance with the level of total shareholder return of the Company's stock price achieved relative to a peer group during the specified period. Following the date of grant, rights to dividends will accrue on the maximum number of shares and may be forfeited if the market or service conditions are not achieved. The Company measures the fair value of these restricted stock awards at the grant date using a Monte Carlo simulation model and amortizes the fair value over the longer of the requisite period or performance period. The Company estimates expected volatility based on the actual volatility of the Company's daily closing share price since listing on September 27, 2013 and the historical volatility of comparable publicly traded companies for a period that is equal to the performance period. The risk-free interest rate is based on the yield on U.S. government bonds for a period commensurate with the performance period. The initial TSR performance was measured using actual historical TSR performance of the Company and of comparable publicly traded companies over the period January 1, 2015 to April 9, 2015. The following table summarizes TSR-RSAs activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Grant-Date Nonvested at December 31, 2014 — N/A Granted 85,268 $ 39.16 Vested — N/A Forfeited — N/A Repurchased for employee tax withholding — N/A Nonvested at December 31, 2015 85,268 $ 39.16 The weighted-average grant-date fair value of our TSR-RSAs granted was $39.16 per share during the year ended December 31, 2015 . As of December 31, 2015 , the total unrecorded stock-based compensation expense related to nonvested TSR-RSAs was $1.7 million , which is expected to be amortized over a weighted-average period of 2.2 years . RSAs that contain Performance Conditions During the year ended December 31, 2014, the Company recorded compensation expense of $0.6 million related to RSAs, granted in March 2014, that were released to senior management personnel when certain performance conditions were met. These awards included 27,717 shares of restricted stock, with a weighted average grant date fair value of $27.03 that were released upon the Company achieving its cash available for distribution target as of December 31, 2014. On December 31, 2014, the performance condition was met. As of December 31, 2015, there were no nonvested RSAs that contain performance conditions. Restricted Stock Units On January 2, 2015, the Company granted time-based deferred RSUs to certain directors. Deferred RSUs are equity awards that entitle the holder the right to receive shares of the Company's common stock upon vesting and are settled on, or as soon as administratively possible after, the settlement date which is January 1 following the date of the director's termination of service. The Company measures the fair value of deferred RSUs 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 RSU activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Grant-Date Nonvested at December 31, 2014 — N/A Granted 22,772 $ 25.94 Vested (22,772) $ 25.94 Forfeited — N/A Repurchased for employee tax withholding — N/A Nonvested at December 31, 2015 — N/A For the year ended December 31, 2015 , the total fair value of deferred RSUs vested was $0.6 million . The weighted-average grant date fair value of stock awards granted during the same period was $25.94 . As of December 31, 2015, there were no nonvested deferred RSUs.

Loss Per Share

Loss Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Loss Per Share	Loss Per Share The Company computes loss per share attributable to common stockholders using the two-class method as the Company has outstanding shares that meet the definition of participating securities. The two-class method is used to determine net income (loss) per share for each class of common stock and participating securities according to dividends declared or accumulated in undistributed earnings. The two-class method requires income available to common stockholders for the period to be allocated between common and participating securities based on their respective rights to receive dividends as if all income for the period has been distributed. The Company computes basic loss per share by dividing net income (loss) attributable to common stockholders (adjusted by net income (loss) allocated to participating securities) by the weighted-average number of shares outstanding for the period. Diluted net income (loss) attributable to common stockholders is adjusted to reallocate undistributed earnings based on the potential impact of dilutive securities (i.e. convertible senior notes). Diluted loss per share is computed by dividing diluted net income (loss) attributable to common stockholders by the weighted-average number of shares outstanding for the period, adjusted for the inclusion of potentially dilutive common shares assuming the dilutive effect of stock options, RSAs, RSUs and convertible senior notes. The Company's deferred RSUs are deemed to be participating securities upon vesting, prior to release, as the vested units entitle each holder to nonforfeitable dividend rights. The Company's Class B common stock, which was converted to Class A common stock on a one-to-one basis on December 31, 2014 were deemed to be participating securities as Class B common stock holders had the same rights, including voting and liquidation rights, as Class A common stockholders, except with respect to net income and dividends as Class B common stockholders were not entitled to distributions. Class B common stock had deemed dividends which represented the accretion of the beneficial conversion feature. Potentially dilutive securities are determined by applying the treasury stock method to the assumed exercise of in-the-money stock options and the assumed vesting of outstanding RSAs and release of RSUs. Potentially dilutive securities related to convertible senior notes are determined using the if-converted method. For the years ended December 31, 2015, 2014 and 2013, the Company excluded 3.5 million, 15.6 million and 15.6 million, respectively, of potentially dilutive securities from the diluted EPS calculation as their effect is anti-dilutive. The computations for Class A basic and diluted loss per share are as follows (in thousands except share data): Year ended December 31, 2015 2014 2013 Numerator for basic and diluted loss per share: Net loss attributable to Pattern Energy $ (32,533 ) $ (31,290 ) $ (13,336 ) Less: dividends declared on Class A common shares (102,861 ) (56,976 ) (11,103 ) Less: deemed dividends on Class B common shares — (21,901 ) — Less: earnings allocated to participating securities (32 ) — — Undistributed loss attributable to common stockholders $ (135,426 ) $ (110,167 ) $ (24,439 ) Denominator for loss per share: Weighted average number of shares: Class A common stock - basic and diluted 70,535,568 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 $ 1.46 $ 1.34 $ 0.31 Undistributed loss (1.92 ) (1.90 ) (0.48 ) Basic loss per share $ (0.46 ) $ (0.56 ) $ (0.17 ) Class A common stock: Diluted loss per share $ (0.46 ) $ (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 ) Dividends declared per Class A common share $ 1.43 $ 1.30 $ 0.31 Deemed dividends per Class B common share $ — $ 1.41 $ —

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments The following table summarizes estimates of future commitments related to the various agreements that the Company has entered into (in thousands): 2016 2017 2018 2019 2020 Thereafter Total Purchase, construction and other commitments $ 20,661 $ 1,419 $ 563 $ 554 $ 591 $ 5,605 $ 29,393 Operating leases 11,103 12,069 14,156 14,637 14,811 285,977 352,753 Service and maintenance agreements 56,802 51,668 40,936 34,149 31,556 146,981 362,092 Total commitments $ 88,566 $ 65,156 $ 55,655 $ 49,340 $ 46,958 $ 438,563 $ 744,238 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 include those related to construction, purchases of wind turbine spare parts from a third party contractor under a parts and service agreement, and commitments related to donations to local community and government organizations. In accordance with the Company’s acquisition of the membership interests in Amazon Wind Farm Fowler Ridge as referenced in Note 3 , Acquisitions - Asset Acquisition - Amazon Wind Farm Fowler Ridge, the Company acquired an agreement between Pattern Development and an unrelated third party, whereby the unrelated third party is entitled to 1% of the gross revenue received by the project under the PPA which is effective in January 2016 and is estimated to be approximately $2.5 million over 13 years . Operating Leases The Company has entered into various long-term operating lease agreements related to lands for its wind farms. For the years ended December 31, 2015, 2014 and 2013, the Company recorded rent expenses of $12.0 million , $8.8 million and $6.1 million , respectively, in project expense in its consolidated statements of operations. On February 3, 2016, the Company entered into a lease agreement for office facilities in Houston, Texas, effective July 2016, to replace the Pattern Development-leased office facilities which expires in June 2016. Total future commitments are included in operating leases in the table above. See Note 21, Subsequent Events , for additional information. Effective January 1, 2016, Pattern Development assigned to the Company, all of Pattern Development’s rights, title, commitments and interest under an office lease, dated as of September 9, 2009, with respect office space in San Francisco. As a result of this lease assignment, the Company assumed remaining rental commitments under the lease plus certain annual operating expense reimbursements and customary security deposits. Concurrently with the lease assignment, the Company entered into an extension through 2026 of the office lease, which previously terminated at the end of February 2017. Total future commitments are included in operating leases in the table above. See Note 21, Subsequent Events , for additional information. Service and Maintenance Agreements The Company has entered into service and maintenance agreements with third party contractors to provide turbine operations and maintenance services and modifications and upgrades for varying periods over the next 19 years . The computation of outstanding commitments includes an estimated annual price adjustment for inflation of 2% , where applicable. Letters of Credit Power Sale Agreements The Company owns and operates wind power projects, and has entered into various long-term PSAs that terminate from 2019 to 2039 . The terms of these agreements 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 agreement. Under the terms of these agreements, as of December 31, 2015, the Company issued irrevocable letters of credits to guarantee its performance for the duration of the agreements totaling $229.2 million . 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, 2015, the Company issued irrevocable letters of credit totaling $108.1 million to ensure performance under these various project finance agreements. Contingencies Turbine Operating Warranties and Service Guarantees 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, an amount for each percent that the turbine operates below the minimum availability threshold. In addition, 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, 2015, the Company recorded liabilities of $0.8 million associated with bonuses payable to the turbine manufacturers. The Company also has service guarantees from its turbine service and maintenance providers. These service guarantees, primarily from one provider, are associated with long-term turbine service arrangements which commenced on various dates in 2014 and 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, an amount 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, 2015, the Company recorded liability of $1.4 million associated with bonuses payable to service providers. Legal Matters 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. Indemnity The Company provides a variety of indemnities in the ordinary course of business to contractual counterparties and to its lenders and other financial partners. The Company is party to certain indemnities for the benefit of project finance lenders and tax equity partners of certain projects. These consist principally of indemnities that protect the project finance lenders from, among other things, the potential effect of any recapture by the U.S. Department of the Treasury of any amount of the Cash Grants previously received by the projects and eligibility of production tax credits and certain legal matters, limited to the amount of certain related costs and expenses.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	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 report to the Company’s executive officers. Pursuant to the Management Services Agreement, certain of the Company’s executive officers, including its Chief Executive Officer, "shared PEG executives." 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 shared PEG executives have responsibilities for both the Company and Pattern Development and, as a result, these individuals do 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 following table presents net bilateral management service cost reimbursements included in the consolidated statements of operations (in thousands): Year Ended December 31, 2015 2014 2013 Project expense $ — $ — $ 1,995 Related party general and administrative 7,589 5,787 $ 8,169 Related party income (2,665 ) (2,612 ) $ (665 ) Other (expense) income, net — — $ (551 ) Total $ 4,924 $ 3,175 $ 8,948 As of December 31, 2015 and 2014 , the net amounts payable to Pattern Development for bilateral management service cost reimbursements were $1.6 million and $0.8 million , respectively. In addition, the Company recorded a receivable of $0.1 million and $0.1 million for the years ended December 31, 2015 and 2014 , respectively, related to expense reimbursements due from Pattern Development. Purchase and Sales Agreements On December 20, 2013, the Company acquired a 45% interest in Grand from Pattern Development. Subject to the terms of the agreement, the Company was required to make a potential contingent payment of up to C $5.0 million . In September 2015, the Company settled the contingent obligation and made a payment of C$2.4 million , or $1.8 million calculated based on the September 2015 average exchange rate, as calculated based on final budget to actual amounts and distributions payable to Pattern Development upon term conversion. On July 28, 2015, the Company acquired a 27% interest in the Gulf Wind project from Pattern Development for a cash purchase price of approximately $13.0 million . See Note 15 , Stockholders' Equity - Noncontrolling Interests, for additional information. On June 17, 2015 , the Company acquired a one-third equity interest in K2 from Pattern Development for a purchase price of approximately $128.4 million , plus assumed proportionate debt of approximately $221.8 million , U.S. dollar equivalent. In November 2015, upon term conversion, an additional $4.0 million of contingent consideration became due payable to the seller, resulting in an adjusted purchase price of approximately $132.4 million . This represents a 90 MW interest in the 270 MW wind project, located in the Township of Ashfield-Colborne-Wawanosh, Ontario. On April 29, 2015 , the Company acquired 100% of the membership interests in Fowler Ridge IV Wind Farm LLC through the acquisition of Fowler Ridge IV B Member LLC from Pattern Development for a purchase price of approximately $37.5 million , paid at closing, plus $0.6 million of capitalized transaction expenses. On December 18, 2015, pursuant to the Purchase and Sale Agreement between the Company and Pattern Development, the Company settled a contingent obligation and made a payment of $27.2 million upon tax equity funding. Amazon Wind Farm Fowler Ridge is a 150 MW wind project located in Benton County, Indiana. 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 , and an assumed liability to a third-party. Logan’s Gap is a 164 MW wind project located in Comanche County, Texas. On November 10, 2014 , the Company completed its acquisition of 100% of the Class B membership interest 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 LLC, 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 June 30, 2014 , the Company acquired 100% of the Class B membership interest 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 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. Management fees The Company provides management services and receives a fee for such services under agreements with its joint venture investees, South Kent, Grand, K2 and El Arrayán, prior to the AEI EL Arrayán acquisition on June 25, 2014, in addition to various Pattern Development subsidiaries. Management fees of $3.6 million , $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, 2015 , 2014 , and 2013 , respectively, and a related party receivable of $0.6 million and $0.7 million was recorded in the consolidated balance sheets as of December 31, 2015 and 2014 , respectively. 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 or Canada Revenue Agency 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, 2015 , 2014 and 2013 , the Company contributed $0.5 million , $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.

Selected Quarterly Financial Da

Selected Quarterly Financial Data	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data	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, 2015. The quarterly consolidated statements of operations data were prepared on a basis consistent with the audited consolidated financial statements included 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, 2015 2015 2015 2015 Revenue $ 90,597 $ 89,697 $ 84,671 $ 64,866 Gross profit $ 16,674 $ 22,250 $ 22,348 $ 10,564 Net (loss) income $ (3,873 ) $ (35,332 ) $ 5,657 $ (22,059 ) Net loss attributable to noncontrolling interest $ (6,327 ) $ (5,927 ) $ (8,660 ) $ (2,160 ) Net income (loss) attributable to Pattern Energy $ 2,454 $ (29,405 ) $ 14,317 $ (19,899 ) Basic and diluted earnings (loss) per share—Class A common stock $ 0.03 $ (0.40 ) $ 0.21 $ (0.30 ) Cash dividends declared per Class A common share $ 0.37 $ 0.36 $ 0.35 $ 0.34 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 income (loss) attributable to noncontrolling interest $ 4,406 $ (2,073 ) $ (4,032 ) $ (7,010 ) Net (loss) income attributable to Pattern Energy $ (20,392 ) $ (7,208 ) $ 11,199 $ (14,889 ) Basic (loss) earnings per share—Class A common stock $ (0.36 ) $ (0.15 ) $ 0.17 $ (0.20 ) Diluted (loss) earnings per share—Class A common stock $ (0.36 ) $ (0.15 ) $ 0.16 $ (0.29 ) Basic and diluted (loss) earnings 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 per Class B common share $ 0.46 $ 0.46 $ 0.48 $ —

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On February 24, 2016, the Company approved an increased dividend for the first quarter 2016, payable on April 29, 2016, to holders of record on March 31, 2016, in the amount of $0.3810 per Class A share, which represents $1.524 on an annualized basis. This represents a 2.4% increase from the fourth quarter 2015 dividend of $0.3720 . On February 3, 2016, the Company entered into a lease agreement for office facilities in Houston, Texas, effective July 2016, to replace the Pattern Development-leased office facilities which expires in June 2016. Total future rental commitments under this lease agreement is approximately $14.1 million , including certain annual operating expense reimbursements. The new lease agreement expires in February 2027. Effective January 1, 2016, Pattern Development assigned to the Company, all of Pattern Development’s rights, title, commitments and interest under an office lease, dated as of September 9, 2009, with respect to office space in San Francisco. As a result of this lease assignment, the Company assumed remaining rental commitments under the lease plus certain annual operating expense reimbursements and customary security deposits. Concurrently with the lease assignment, the Company entered into an extension through 2026 of the office lease, which previously terminated at the end of February 2017. Total future commitments assumed under the extended lease agreement are approximately $38.7 million , plus certain annual operating expense reimbursements.

Schedule I-Condensed Parent-Com

Schedule I-Condensed Parent-Company Financial Statements	12 Months Ended
	Dec. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
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, 2015 December 31, 2014 Assets Current assets: Cash and cash equivalents $ 26,938 $ 34,772 Related party receivable 3,050 1,982 Derivative assets, current 3,482 — Current net deferred tax assets — 307 Prepaid expenses 487 514 Other current assets 381 3,970 Total current assets 34,338 41,545 Restricted cash 250 — Investments in subsidiaries 918,270 586,641 Investments in affiliates 116,473 29,079 Derivative assets 628 — Net deferred tax assets — 147 Other assets — 85 Total assets $ 1,069,959 $ 657,497 Liabilities and equity Current liabilities: Accounts payable and other accrued liabilities $ 7,590 $ 6,404 Related party payable 1,643 757 Accrued interest 3,842 — Dividend payable 28,022 15,734 Current deferred tax liabilities — 147 Total current liabilities 41,097 23,042 Convertible senior notes, net of financing costs of $5,014 and $0 as of December 31, 2015 and 2014, respectively 197,362 — Net deferred tax liabilities — 307 Total liabilities 238,459 23,349 Equity: Class A common stock, $0.01 par value per share: 500,000,000 shares authorized; 74,644,141 and 62,062,841 shares outstanding as of December 31, 2015 and 2014, respectively 747 621 Additional paid-in capital 955,254 696,378 Capital — — Accumulated loss (49,599 ) (17,066 ) Accumulated other comprehensive loss (73,325 ) (45,068 ) Treasury stock, at cost; 65,301 and 25,465 shares of Class A common stock as of December 31, 2015 and 2014, respectively (1,577 ) (717 ) Total equity 831,500 634,148 Total liabilities and equity $ 1,069,959 $ 657,497 Statements of Operations and Comprehensive Income (Loss) (In thousands of U.S. dollars) Year ended December 31, 2015 2014 2013 Revenue $ — $ — $ — Expenses 29,483 23,089 3,630 Operating loss (29,483 ) (23,089 ) (3,630 ) Other income (expense): Interest expense (6,107 ) — — Equity in (losses) earnings from subsidiaries (19,058 ) 18,064 12,641 Equity in earnings (losses) from affiliates 16,119 (25,295 ) 7,846 Gain on undesignated derivatives 5,107 — — Related party income 2,665 2,612 665 Other expenses, net (1,558 ) (3,566 ) (563 ) Other (expense) income (2,832 ) (8,185 ) 20,589 Net (loss) income before income tax (32,315 ) (31,274 ) 16,959 Tax provision 218 16 — Net (loss) income (32,533 ) (31,290 ) 16,959 Other comprehensive (loss) income: Proportionate share of subsidiaries' other comprehensive (loss) income, net of tax benefit of $1,206, $514 and $0, respectively (16,085 ) (30,724 ) 23,478 Proportionate share of affiliates' other comprehensive (loss) income activity, net of tax benefit (provision) of $1,524, $1,855 and ($615), respectively (4,228 ) (5,991 ) 2,473 Total other comprehensive (loss) income, net of tax (20,313 ) (36,715 ) 25,951 Comprehensive (loss) income $ (52,846 ) $ (68,005 ) $ 42,910 Condensed Financial Information of Parent Condensed Statements of Cash Flows (In thousands of U.S. dollars) Year ended December 31, 2015 2014 2013 Operating activities Net (loss) income $ (32,533 ) $ (31,290 ) $ 16,959 Adjustments to reconcile net (loss) income to net cash used in operating activities: Amortization of financing costs 472 — — Amortization of debt discount 1,794 — — Gain on derivatives (4,110 ) — — Stock-based compensation 4,462 4,105 511 Net loss on transactions — 1,473 — Equity in losses (earnings) from subsidiaries 19,058 (18,064 ) (12,641 ) Equity in (earnings) losses from affiliates (16,119 ) 25,295 (7,846 ) Changes in operating assets and liabilities: Prepaid expenses 35 (93 ) (428 ) Other current assets 43 (3,452 ) (18 ) Accounts payable and other accrued liabilities 473 1,999 93 Related party receivable/payable (183 ) (639 ) (1,007 ) Accrued interest payable 3,842 — — Net cash used in operating activities (22,766 ) (20,666 ) (4,377 ) Investing activities Cash paid for acquisitions, net of cash acquired (65,042 ) — — Distribution from subsidiaries (613,089 ) 108,581 233,226 Contribution to subsidiaries 244,969 (362,533 ) (172,130 ) Increase in restricted cash (250 ) — — Net cash (used in) provided by investing activities (433,412 ) (253,952 ) 61,096 Financing activities Proceeds from public offering, net of expenses 317,432 286,757 317,926 Proceeds from issuance of convertible senior notes, net of issuance costs 218,929 — — Proceeds from exercise of stock options — 327 — Refund for deposit for letters of credit 3,425 — — Repurchase of shares for employee tax withholding (860 ) (693 ) (24 ) Capital contributions - Pattern Development — — 32,678 Capital distributions - Pattern Development — — (98,884 ) Capital distributions - Contribution Transactions — — (232,640 ) Dividends paid (90,582 ) (52,344 ) — Payment for deferred equity issuance costs — (433 ) — Net cash provided by financing activities 448,344 233,614 19,056 Net change in cash and cash equivalents (7,834 ) (41,004 ) 75,775 Cash and cash equivalents at beginning of period 34,772 75,776 1 Cash and cash equivalents at end of period $ 26,938 $ 34,772 $ 75,776 Supplemental disclosures Cash payments for income taxes $ 218 $ 16 $ — Equity issuance costs paid in prior period related to current period offerings $ (433 ) $ — $ — Schedule of non-cash activities Non-cash increase in additional paid-in capital from buyout of noncontrolling interests $ 16,715 $ — $ — 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 Accoun31

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
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.
Change in Depreciable Lives of Property, Plant and Equipment	Change in Depreciable Lives of Property, Plant and Equipment The Company periodically reviews the estimated economic useful lives of its fixed assets. In 2015, based on technical review of various wind farm characteristics, the expected economic useful lives of certain wind farms were longer than the estimated economic useful lives used for depreciation purposes in the Company’s financial statements. As a result, effective January 1, 2015, the Company changed its estimate of the economic useful lives of wind farms for which construction began after 2011, from 20 to 25 years. All other wind farms continue to depreciate over an estimated economic useful life of 20 years. For the year ended December 31, 2015 , the effect of this change reduced depreciation expense by $14.7 million , decreased net loss by $13.9 million , net of tax, and decreased Class A basic and diluted loss per share by $0.09 .
Reclassification	Reclassification Certain prior period balances have been reclassified to conform to the current period presentation in the Company’s consolidated financial statements and the accompanying notes. The Company has also revised its consolidated statements of comprehensive income (loss) for the years December 31, 2014 and 2013 to correct an immaterial classification error. The consolidated statements of comprehensive income (loss) for the years ended December 31, 2014 and 2013 have been corrected to reflect the reclassification of approximately $27.5 million and $23.9 million , respectively, between the effective portion of change in fair market value of derivatives and reclassification to net loss attributable to Pattern Energy. The consolidated statements of comprehensive income (loss) for the years ended December 31, 2014 and 2013 have also been corrected to reflect the reclassification of approximately $7.2 million and $3.8 million , respectively, between the effective portion of change in fair market value of derivatives and reclassification to net loss for noncontrolling interest. These revisions had no impact on comprehensive loss or comprehensive loss attributable to noncontrolling interest. Changes in accumulated other comprehensive loss by component, as disclosed in Note 12 , Accumulated Other Comprehensive Loss , have also been corrected to reflect this immaterial error correction.
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.
Business Combinations	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, including contingent consideration, 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. Transaction costs associated with business combinations are expensed as incurred.
Asset Acquisitions	Asset Acquisitions When the Company acquires assets and liabilities that do not constitute a business, the fair value of the purchase consideration, including transaction costs of the asset acquisition, is assumed to be equal to the fair value of the net assets acquired and is allocated to the individual assets and liabilities assumed based on their relative fair values. Contingent consideration associated with the acquisition is generally recognized when the contingency is resolved. No goodwill is recognized in an asset acquisition. Transaction costs associated with asset acquisitions are capitalized as part of the investment.
Equity Method Investments	Equity Method Investments When the Company acquires a noncontrolling interest in an entity where it is not the primary beneficiary, does not control any of the ongoing activities of the entity, and does not meet consolidation requirements of ASC 810, Consolidation of Variable Interest Entities, the investment is initially recognized as an equity method investment at cost. Any basis difference related to the property, plant and equipment will be amortized over the estimated economic useful life of the underlying long-lived assets. A basis difference related to the PPA will be amortized over the remaining term of the PPA. Transactions costs associated with equity method investments are capitalized as part of the investment.
Noncontrolling Interests	Noncontrolling Interests Noncontrolling interests represent the portion of the Company’s net income (loss), net assets and comprehensive income (loss) that is not allocable to the Company and is calculated based on ownership percentage, for applicable projects. For the noncontrolling interests in the Company’s Panhandle 1, Panhandle 2, Post Rock, Logan's Gap and Amazon Wind Farm Fowler Ridge projects, and the Company's Gulf Wind project prior to the acquisition of the noncontrolling interests in July 2015, 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 the projects were liquidated at recorded amounts determined in accordance with U.S. GAAP and distributed to the investors. The noncontrolling interest in the results of operations and comprehensive income (loss) 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 the projects and the third party. The noncontrolling interest balances in the projects 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 income (loss), net of tax, in the accompanying consolidated statements of stockholders’ equity and comprehensive income (loss). Where the U.S. dollar is the functional currency, re-measurement adjustments are recorded in other (expense) 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, reimbursable interconnection costs and derivative instruments. The Company’s cash and cash equivalents are with high quality 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; however, the Company believes that its credit risk is immaterial. In addition, reimbursable interconnection costs are with large creditworthy utility companies and the Company’s derivative instruments are placed with counterparties that are creditworthy institutions. The Company sells electricity and RECs primarily to creditworthy utilities under long-term, fixed-priced power sale arrangements ("PSAs"). During the year ended December 31, 2015 , Standard & Poor’s Rating Services ("S&P") further downgraded the credit rating of the Puerto Rico Electric Power Authority ("PREPA") from CCC to CC. Through December 31, 2015 , Moody’s Investor Service’s credit rating of PREPA remains unchanged at Caa3. As of February 29, 2016 , 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 18, 2016 . The table below presents significant customers who accounted for greater than 10% of total revenue, and PREPA, and the related maximum amount of credit loss based on their percentages of total trade receivables as of December 31, 2015 , 2014 and 2013 : Year ended December 31, 2015 2014 2013 Revenue Trade Receivables Revenue Trade Receivables Revenue Trade Receivables San Diego Gas & Electric 17.07 % 17.03 % 22.09 % 14.13 % 16.31 % 26.21 % PREPA 8.42 % 8.80 % 9.29 % 6.91 % 8.21 % 16.88 % The Independent Electricity System Operator ("IESO") of Ontario, Canada is the customer for each of the Company’s Grand, K2 and South Kent projects. The Company accounts for these projects under the equity method of accounting and as a result, the Company’s ownership interest in these projects is recorded in equity in earnings (losses) in unconsolidated investments and not in revenue. As such, IESO is not included in the foregoing table of significant customers. However, we rely on a limited number of key power purchasers, including IESO, and face a concentration of credit risk from IESO as a customer.
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 which may 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 13 , 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 4 , Property, Plant and Equipment .
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist of cash balances and highly-liquid investments with original maturities of three months or less.
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, PSAs 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, primarily to creditworthy utilities. The Company believes that all amounts are collectible and an allowance for doubtful accounts is not required as of December 31, 2015 and 2014 .
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 either when the project reaches commercial operation or as energy is delivered over the life of the PPA.
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.
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. 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. The Company begins capitalizing deferred development costs as a component of construction in progress on the date the project commences construction. Once the project achieves commercial operation, the Company reclassifies the amounts recorded in construction in progress to property, plant and equipment.
Finite-Lived Intangible Assets and Liability	Finite-Lived Intangible Assets and Liability Finite-lived intangible assets include PPAs, easements, land options and mining rights. PPAs obtained through acquisitions are valued at the time of acquisition and the difference between the contract price and the estimated fair value results in an intangible asset or an intangible liability. If the contract price is higher than the estimated fair value, the Company will recognize an intangible asset. If the contract price is lower than the estimated fair value, the Company will recognize an intangible liability. Easements, land options and mining rights are recognized at the carryover basis from the seller. The Company amortizes its intangible asset and liability associated with PPAs using the straight-line method over the remaining term of the related PPA. At the date of acquisition, the weighted average amortization period of the intangible asset associated with the PPA is approximately 15 years and the weighted average amortization period of the intangible liability is approximately 17 years. The Company amortizes easements, land options and mining rights 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 approximately 5 - 25 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 for which construction began before 2011 are depreciated over 20 years and wind farms for which construction began after 2011 are depreciated over 25 years . The remaining assets are depreciated over two to five years. 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. During the year ended December 31, 2015 , the Company recorded impairment charges of $0.4 million related to the write-off of certain furniture, fixtures and equipment in project expenses in the consolidated statements of operations.
Derivatives	Derivatives The Company may enter into interest rate swaps, interest rate caps, forwards and other agreements to manage its interest rate, electricity price and foreign exchange rate risk. 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. The Company does not have contracts subject to master netting agreements with counterparties, as such assets and liabilities are presented gross on the consolidated balance sheets. Contracts used in normal business operations that are settled by physical delivery, among other criteria, are eligible for and may be designated as NPNS. NPNS contracts do not meet the definition of derivatives, and therefore, contracts associated with the sale of energy are recognized as electricity sales and contracts associated with the production of electricity are recognized as project expense on the consolidated statements of operations. Accounting for changes in the fair value 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 qualify and 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 income (loss) ("OCI"), until the contract settles and the hedged item is recognized in earnings. The ineffective portion of change in fair value is recorded as a component of net income (loss) on the consolidated statements of operations. The Company discontinues hedge accounting when it has determined that a derivative contract no longer qualifies as an effective hedge or when it is no longer probable that the hedged forecasted transaction will occur. When the Company discontinues hedge accounting, associated deferred amounts are immediately recognized into earnings and future changes in fair value, if any, are recognized in earnings. For undesignated derivative instruments, the change in fair value is reported as a component of net income (loss) on the consolidated statements of operations.
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. Deferred financing costs are capitalized and recorded as an offset to the respective loans in the Company's consolidated balance sheets and are amortized to interest expense in the consolidated statements of operations. Financing costs related to the revolving credit facility are capitalized and recorded as a long-term asset in the Company's consolidated balance sheets and are amortized to interest expense in the Company's consolidated statements of operations, over the life of its life using the effective-interest method.
Income Taxes	Income Taxes 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, Income Taxes, 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% 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 either acquired through business combinations or asset acquisitions. Contingent obligations that are acquired through business combinations are recorded at fair value on the date of acquisition while contingent obligations that are acquired through asset acquisitions are recorded generally when the contingency is resolved. The Company’s contingent liabilities related to turbine availability warranties with turbine manufacturers and turbine availability guarantees associated with long-term turbine service arrangements are reported at net realizable value. Pursuant to these warranties and guarantees, if a turbine operates at less than minimum availability during the warranty or guarantee period, the manufacturer or service provider is obligated to pay, as liquidated damages, an amount for each percent that the turbine operates below the minimum availability threshold. In addition, pursuant to certain of these warranties and guarantees, if a turbine operates at more than a specified availability during the warranty or guarantee period, the Company has an obligation to pay a bonus to the turbine manufacturer or service provider.
Asset Retirement Obligation	Asset Retirement Obligation The Company records asset retirement obligations ("AROs") for the estimated costs of decommissioning turbines, removing above-ground installations and restoring sites, at the time when a contractual decommissioning obligation is incurred. AROs represent the present value of the expected costs and timing of the related decommissioning activities. The ARO assets and liabilities are recorded in property, plant and equipment and other long-term liabilities, respectively, in the consolidated balance sheets. 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 consolidated statements of operations using accretion rates based on credit adjusted risk-free interest rates. Changes resulting from revisions to the timing or amount of the original estimate of cash flows are recognized as an increase or a decrease in the asset retirement cost, or income when the asset retirement cost is depleted.
Revenue Recognition	Revenue Recognition The Company sells electricity and related renewable energy credits under the terms of the PSAs or at market prices. Revenue is recognized based upon the amount of electricity delivered at rates specified under the contracts, or at market prices for spot market transactions, assuming all other revenue recognition criteria are met. When renewable energy credits are sold as a separate component, revenue is recognized at the time title to the energy credits is transferred to the buyer. Depending on the terms of the PSA, the Company may account for the contracts as operating leases pursuant to ASC 840, Leases , or derivative instruments pursuant to ASC 815, Derivatives and Hedging . In considering ASC 840 , Leases , it was determined that certain of the Company's PSAs are operating leases. ASC 840, Leases , requires minimum lease payments to be recognized over the term of the lease and contingent rents to be recorded when the achievement of the contingency becomes probable. All energy sales under the PSAs are considered contingent rent due to the inherent uncertainty and variability. None of the operating leases have minimum lease payments; therefore, revenue from these contracts and any related renewable energy attributes are recognized as electricity sales when delivered. Contracts that meet the NPNS scope exception to derivative accounting are accounted for under the accrual method, where revenues are recorded in the period they are earned. Energy derivative instruments that reduce exposure to changes in commodity prices may allow the Company to lock in a fixed price per MWh for a specified amount of annual electricity generation over the life of the swap contract. Monthly settlement amounts under energy hedges are accounted for as energy derivative settlements in the consolidated statements of operations. Changes in the fair value of energy hedges are recorded in electricity sales 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 Black-Scholes option pricing model includes assumptions regarding dividend yields, expected volatility, expected option term, expected forfeiture rate and risk-free interest rates. Expense is recognized by amortizing the fair value of the stock options granted using a straight-line method over the applicable vesting period; accordingly, stock based compensation is netted for estimated forfeitures. 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 and restricted stock unit grants by amortizing the fair value of the restricted stock award grants, which is the grant date market price, over the applicable vesting period. For certain restricted stock award grants, the Company measures the fair value at the grant date using a Monte Carlo simulation model and amortizes the fair value over the longer of the requisite period or performance period. The Monte Carlo simulation model includes assumptions regarding dividend yields, expected volatility, risk-free interest rates and initial total shareholder return ("TSR") performance. Stock-based compensation expense is recorded as a component of general and administrative expenses in the Company’s consolidated statements of operations.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) consists of net income (loss) and other comprehensive income (loss), net of tax. Other comprehensive income (loss), net of tax included in accumulated other comprehensive income (loss) in the accompanying consolidated statements of stockholders’ equity, is comprised primarily of changes in foreign currency translation adjustments and the effective portion of 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 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-02, "Leases," which requires lessees to recognize right-of-use assets and lease liabilities, for all leases, with the exception of short-term leases, at the commencement date of each lease. Under the new guidance, lessor accounting is largely unchanged. ASU 2016-02 simplifies the accounting for sale and leaseback transactions primarily because lessees must recognize lease assets and liabilities. ASU 2016-02 is effective for annual periods beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted. The amendments of this update should be applied using a modified retrospective approach, which requires lessees and lessors to recognize and measure leases at the beginning of the earliest period presented. The Company is currently assessing the future impact of this update on its consolidated financial statements and related disclosures and expects to adopt this update beginning January 1, 2019. In November 2015, the FASB issued ASU 2015-17, "Income Taxes: Balance Sheet Classification of Deferred Taxes," which eliminates the current requirement for organizations to present deferred tax liabilities and assets as current and non-current in a classified balance sheet. Instead, organizations will be required to classify all deferred tax assets and liabilities as non-current. ASU 2015-17 is effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods. The amendments may be applied prospectively to all deferred tax liabilities and assets or retrospectively to all periods presented. Early adoption is permitted for financial statements that have not been previously issued. The Company early adopted ASU 2015-17 for the year ended December 31, 2015 and has applied the guidance prospectively. No changes have been made to the prior period presentation. In September 2015, the FASB issued ASU 2015-16, "Business Combinations: Simplifying the Accounting for Measurement-Period Adjustments," which requires an acquirer to recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. The amendments under ASU 2015-16 require that the acquirer record, in the same period's financial statements, the effect on earnings of changes in depreciation, amortization, or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. ASU 2015-16 also requires an entity to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods, if the adjustment to the provisional amounts had been recognized as of the acquisition date. ASU 2015-16 is effective for annual reporting periods beginning after December 15, 2015 and interim periods within those fiscal years. The amendments in this update should be applied prospectively to adjustments to provisional amounts that occur after the effective date with earlier application permitted for financial statements that have not been issued. The Company will adopt ASU 2015-16, effective January 1, 2016. The adoption of ASU 2015-16 is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In August 2015, the FASB issued ASU 2015-14, "Revenue from Contracts with Customers: Deferral of the Effective Date" to amend ASU 2015-09 "Revenue from Contracts with Customers" to defer the effective date of ASU 2014-09 for all entities by one year. The guidance in ASU 2014-09 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. Lease contracts within the scope of ASC 840, "Leases", are specifically excluded from ASU No. 2014-09. As a result of this amendment, ASU 2014-09 is now effective for annual reporting periods beginning after December 15, 2017 and interim periods within those fiscal years. Early adoption is permitted only as of annual reporting periods beginning after December 15, 2015 and interim periods within those fiscal years. 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. In June 2015, the FASB voted to defer the effective date by one year, with early adoption permitted as of the original effective date. The Company is currently assessing the future impact of this update on its consolidated financial statements and related disclosures and expects to adopt this update beginning January 1, 2018. In August 2015, the FASB issued ASU 2015-13, "Derivatives and Hedging: Application of the Normal Purchases and Normal Sales Scope Exception to Certain Electricity Contracts within Nodal Energy Markets" to allow the application of the normal purchases and normal sales scope exception to certain electricity contracts within nodal energy markets. The amendments specify that the purchase or sale of electricity on a forward basis within nodal energy markets does not cause that contract to fail to meet the physical delivery criterion of the normal purchases and normal sales scope exception. The amendments in this update are effective upon issuance and are in line with the Company’s current accounting policies. The adoption of ASU 2015-13 did not have an impact to the Company’s consolidated financial statements and related disclosures. In June 2015, the FASB issued ASU 2015-10, "Technical Corrections and Improvements" which covers a wide range of topics in the Accounting Standards Codification (the "Codification"). The amendments in this update represent changes to clarify the Codification, correct unintended application of guidance, or make minor improvements to the Codification that are not expected to have a significant effect on current accounting practice or create a significant administrative cost on most entities. The amendments in ASU 2015-10 were effective immediately upon issuance and the adoption did not have material impact on the Company's consolidated financial statements and related disclosures. In April 2015, the FASB issued ASU 2015-03, "Interest – Imputation of Interest: Simplifying the Presentation of Debt Issuance Costs" to simplify the presentation of debt issuance costs by requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this ASU. ASU 2015-03 is effective for public companies for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years and should be applied retrospectively. Early adoption is permitted for financial statements that have not been previously issued. Upon transition, an entity is required to comply with the applicable disclosures for a change in accounting principle. The Company adopted ASU 2015-03 in April 2015 and applied the change in accounting principle to the consolidated financial statements as of December 31, 2015 . As a result, the Company reclassified $ 26.3 million and $ 36.8 million in total deferred financing costs to long-term debt, of which $ 3.7 million and $ 11.9 million have been reclassified to current portion of long-term debt, as of December 31, 2015 and December 31, 2014 , respectively, on the Company’s consolidated balance sheets. Deferred financing costs related to the Company’s revolving credit facility remain classified as an asset on the Company’s consolidated balance sheets. The adoption of ASU 2015-3 had no impact on the Company’s results of operations and cash flows. In February 2015, the 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 for fiscal years 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 will adopt ASU 2015-16, effective January 1, 2016, and is currently assessing the impact to the Company’s consolidated financial statements and related disclosures. In August 2014, the FASB issued 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 is currently assessing the future impact of this update on its consolidated financial statements and related disclosures and expects to adopt this update beginning January 1, 2017. 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 will adopt ASU 2014-12, effective January 1, 2016 and does not anticipate that the adoption of this update will have a material impact on its consolidated financial statements and related disclosures.

Summary of Significant Accoun32

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
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 greater than 10% of total revenue, and PREPA, and the related maximum amount of credit loss based on their percentages of total trade receivables as of December 31, 2015 , 2014 and 2013 : Year ended December 31, 2015 2014 2013 Revenue Trade Receivables Revenue Trade Receivables Revenue Trade Receivables San Diego Gas & Electric 17.07 % 17.03 % 22.09 % 14.13 % 16.31 % 26.21 % PREPA 8.42 % 8.80 % 9.29 % 6.91 % 8.21 % 16.88 %
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, 2015 2014 2013 2015 2014 United States $ 258,542 $ 201,408 $ 161,505 $ 2,791,259 $ 1,810,414 Canada 39,178 46,593 40,068 184,115 233,690 Chile 32,111 17,492 — 319,246 332,947 Total $ 329,831 $ 265,493 $ 201,573 $ 3,294,620 $ 2,377,051

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2015
Business Acquisition [Line Items]
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) 2015 2014 Pro forma total revenue $ 351,094 $ 326,094 Pro forma total expenses 411,746 389,180 Pro forma net loss (60,652 ) (63,086 ) Less: pro forma net loss attributable to noncontrolling interest (29,091 ) (21,591 ) Pro forma net loss attributable to Pattern Energy $ (31,561 ) $ (41,495 )
Schedule of Amounts Included in Consolidated Statements of Operations	The following table presents the amounts included in the consolidated statements of operations for Lost Creek and Post Rock since their respective dates of acquisition: Year ended December 31, Unaudited data (in thousands) 2015 Total revenue $ 31,093 Total expenses 34,574 Net loss (3,481 ) Less: net loss attributable to noncontrolling interest (5,114 ) Net loss attributable to Pattern Energy $ 1,633
Lost Creek And Post Rock [Member]
Business Acquisition [Line Items]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The fair value of the assets acquired and liabilities assumed in connection with the acquisition are as follows (in thousands): May 15, 2015 Cash and cash equivalents $ 3,501 Restricted cash, current 11,787 Trade receivables 7,910 Prepaid expenses 1,232 Other current assets 444 Restricted cash 4,592 Property, plant and equipment 543,347 Finite-lived intangible assets 97,400 Other assets 17,632 Accounts payable and other accrued liabilities (2,611 ) Accrued interest (951 ) Derivative liabilities, current (3,759 ) Current portion of long-term debt, net of financing costs (7,463 ) Finite-lived intangible liabilities (60,300 ) Asset retirement obligations (7,192 ) Long-term debt, net of financing costs (108,838 ) Derivative liabilities (14,631 ) Total consideration before temporary equity and noncontrolling interests 482,100 Less: temporary equity (35,000 ) Less: noncontrolling interests (205,100 ) Total consideration after temporary equity and noncontrolling interests $ 242,000
Logan's Gap [Member]
Business Acquisition [Line Items]
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 1,790 Deferred financing costs, current 2,882 Construction in progress 23,821 Property, plant and equipment 116 Other assets 80 Accrued construction costs (5,617 ) Current portion of contingent liabilities (7,975 ) Related party payable (5,003 ) Total consideration $ 15,099
Panhandle 2 [Member]
Business Acquisition [Line Items]
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
Panhandle 1 [Member]
Business Acquisition [Line Items]
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
El Arrayan [Member]
Business Acquisition [Line Items]
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
Fowler RidgeIv Wind Farm Llc [Member]
Business Acquisition [Line Items]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The preliminary fair value of the assets acquired and liabilities assumed in connection with the Amazon Wind Farm Fowler Ridge acquisition are as follows (in thousands): April 29, 2015 Prepaid expenses and other current assets $ 1,753 Deferred financing costs, current 2,132 Turbine advances 4,000 Construction in progress 34,487 Finite-lived intangible assets, net of accumulated amortization 2,247 Accrued construction costs (6,549 ) Total consideration $ 38,070

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 2014 Operating wind farms $ 3,700,140 $ 2,624,640 Furniture, fixtures and equipment 3,500 4,366 Land 141 141 Subtotal 3,703,781 2,629,147 Less: accumulated depreciation (409,161 ) (278,291 ) Property, plant and equipment, net $ 3,294,620 $ 2,350,856

Finite-Lived Intangible Asset35

Finite-Lived Intangible Assets and Liability (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Major Components of Finite-Lived Intangible Assets and Liability	The following presents the major components of the finite-lived intangible assets and liability (in thousands): December 31, 2015 Weighted Average Remaining Life Gross Accumulated Amortization Net Intangible assets Power purchase agreement 14 $ 97,400 $ (4,114 ) $ 93,286 Other intangible assets 17 4,679 (243 ) $ 4,436 Total intangible assets $ 102,079 $ (4,357 ) $ 97,722 Intangible liability Power purchase agreement 17 $ (60,300 ) $ 2,168 $ (58,132 ) December 31, 2014 Weighted Average Remaining Life Gross Accumulated Amortization Net Other intangible assets 17 $ 1,411 $ (154 ) $ 1,257
Schedule of Estimated Future Amortization Expense	The following table presents estimated future amortization for the next five years related to the PPA asset and PPA liability and other intangible assets: Year ended December 31, Power purchase agreements, net Other intangible assets 2016 $ 3,049 $ 277 2017 3,031 352 2018 3,031 277 2019 3,031 277 2020 3,049 277 Thereafter 19,963 2,976

Unconsolidated Investments (Tab

Unconsolidated Investments (Tables)	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Projects Accounted under Equity Method of Accounting	The following summarizes the aggregated balance sheets and statements of operations for K2 as of December 31, 2015 and for the year ended December 31, 2015 and statements of operations for El Arrayán for the year ended December 31, 2014, prior to its consolidation in June 2014 and December 31, 2013, pursuant to Regulation S-X Rule 4-08 (g) (in thousands): December 31, 2015 Current assets $ 46,342 Non-current assets 631,151 Total assets $ 677,493 Current liabilities $ 46,901 Non-current liabilities 617,460 Total liabilities 664,361 Total equity 13,132 Total liabilities and equity $ 677,493 Year Ended December 31, 2015 2014 2013 Revenue $ 52,130 $ 1,821 $ — Cost of revenue 18,450 1,060 15 Operating expenses 3,140 682 900 Other expense 10,061 1,341 26 Net (loss) income $ 20,479 $ (1,262 ) $ (941 ) The following projects are accounted for under the equity method of accounting and are presented in the Company's consolidated balance sheets for the periods below (in thousands): December 31, Percentage of Ownership December 31, 2015 2014 2015 2014 South Kent $ 6,185 $ 17,360 50.0 % 50.0 % Grand 5,735 11,719 45.0 % 45.0 % K2 104,553 — 33.3 % N/A Unconsolidated investments $ 116,473 $ 29,079

Accounts Payable and Other Ac37

Accounts Payable and Other Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 2014 Accounts payable $ 625 $ 673 Other accrued liabilities 9,583 7,892 Warranty settlement payments — 639 LTSA/PPE upgrades liability 4,909 680 Turbine operations and maintenance payable 985 1,310 Purchase agreement obligations 5,749 — Land lease rent payable 2,513 2,115 Spare-parts inventory payables 1,181 — Payroll liabilities 5,345 4,453 Property tax payable 11,145 4,625 Sales tax payable 741 2,406 Accounts payable and other accrued liabilities $ 42,776 $ 24,793

Long Term Debt (Tables)

Long Term Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Schedule of Long Term Debt	The Company’s long term project debt for the following periods is presented below (in thousands): As of December 31, 2015 December 31, Contractual Interest Rate Effective Interest Rate 2015 2014 Maturity Project-level Fixed interest rate El Arrayán EKF term loan $ 107,160 $ 109,630 5.56 % 5.56 % March 2029 St. Joseph term loan — 189,472 5.88 % 5.95 % May 2031 Santa Isabel term loan 109,973 112,609 4.57 % 4.57 % September 2033 Variable interest rate Logan's Gap construction loan — 58,691 1.57 % 1.57 % December 2015 Gulf Wind term loan — 156,122 3.28 % 6.59 % (1) March 2020 Ocotillo commercial term loan (5) 208,119 222,175 2.36 % 3.77 % (1) (2) August 2020 Lost Creek term loan 110,846 — 2.19 % 6.49 % (1) September 2027 El Arrayán commercial term loan 97,418 99,665 3.17 % 5.65 % (1) March 2029 Spring Valley term loan 132,670 167,261 2.36 % 4.89 % (1) June 2030 Ocotillo development term loan 104,500 106,700 2.71 % 4.37 % (1) August 2033 St. Joseph term loan (5) 158,181 — 2.46 % 3.84 % November 2033 Imputed interest rate Hatchet Ridge financing lease obligation 214,580 228,288 1.43 % 1.43 % December 2032 1,243,447 1,450,613 Unamortized premium, net (3) 1,380 — Unamortized financing costs (26,303 ) (36,755 ) Current portion (including construction loans) (4) (44,144 ) (109,693 ) Long-term debt, less current portion (including construction loans) $ 1,174,380 $ 1,304,165 (1) Includes impact of interest rate derivatives. See Note 11 , Derivative Instruments , for discussion of interest rate derivatives. (2) In October 2014, the Ocotillo financing agreement was amended to include a margin rate decrease of 1.0% for the commercial term loan. (3) Amount is related to the Lost Creek term loan. (4) Amount is presented net of the current portion of unamortized financing costs of $ 3.7 million and $ 11.9 million as of December 31, 2015 and 2014, respectively. (5) The amortization for the Ocotillo commercial term loan and the St. Joseph term loan are through June 2030 and September 2036, respectively, which differs from the stated maturity date of such loans due to prepayment requirements.
Summary of Principal Payments Due under Long Term Debt	The following are principal payments, excluding deferred financing costs, due under the Company's long-term project debt as of December 31, 2015 for the following years (in thousands): Amount 2016 $ 47,613 2017 51,705 2018 60,438 2019 66,304 2020 69,526 Thereafter 947,861 Total $ 1,243,447
Schedule of Reconciliation of Interest Expense	Interest and commitment fees incurred and interest expense for the long term debt, the revolving credit facility and convertible debt consisted of the following (in thousands): Year Ended December 31, 2015 2014 2013 Interest and commitment fees incurred $ 70,847 $ 59,864 $ 57,478 Capitalized interest, commitment fees, and letter of credit fees (6,607 ) (2,856 ) (4,210 ) Letter of credit fees incurred 4,572 4,377 3,530 Amortization of debt discount/premium, net 1,660 — — Amortization of financing costs 7,435 6,309 6,816 Interest expense $ 77,907 $ 67,694 $ 63,614
Convertible Debt	The following table presents a summary of the equity and liability components of the 2020 Notes (in thousands): December 31, 2015 Principal $ 225,000 Less: Unamortized debt discount (22,624 ) Unamortized financing costs (5,014 ) Carrying value of convertible senior notes $ 197,362 Carrying value of the equity component (1) $ 23,743 (1) Included in the consolidated balance sheets as additional paid-in capital, net of $0.7 million in equity issuance costs.

Asset Retirement Obligation (Ta

Asset Retirement Obligation (Tables)	12 Months Ended
	Dec. 31, 2015
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 obligation (in thousands): December 31, 2015 2014 Beginning asset retirement obligations $ 29,272 $ 20,834 Net additions during the year 13,189 7,195 Foreign currency translation adjustment (411 ) (228 ) Adjustment related to change in useful life (1,907 ) — Accretion expense 2,054 1,471 Ending asset retirement obligations $ 42,197 $ 29,272

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following tables present the fair values of the Company's derivative instruments on a gross basis as reflected on the Company’s consolidated balance sheets (in thousands): December 31, 2015 Derivative Assets Derivative Liabilities Current Long-Term Current Long-Term Fair Value of Designated Derivatives: Interest rate swaps $ — $ — $ 10,034 $ 24,360 Fair Value of Undesignated Derivatives: Interest rate swaps $ — $ 559 $ 4,309 $ 4,299 Energy derivative 20,856 42,827 — — Foreign currency forward contracts 3,482 628 — — Total Fair Value $ 24,338 $ 44,014 $ 14,343 $ 28,659 December 31, 2014 Derivative Assets Derivative Liabilities Current Long-Term Current Long-Term Fair Value of Designated Derivatives: Interest rate swaps $ — $ 525 $ 12,904 $ 17,467 Fair Value of Undesignated Derivatives: Interest rate swaps $ — $ 2,523 $ 3,403 $ — Interest rate cap — 352 — — Energy derivative 18,506 45,969 — — Total Fair Value $ 18,506 $ 49,369 $ 16,307 $ 17,467
Schedule of Notional Amounts of Outstanding Derivative Positions	The following table summarizes the notional amounts of the Company's outstanding derivative instruments (in thousands except for MWh): December 31, Unit of Measure 2015 2014 Designated Derivative Instruments Interest rate swaps USD $ 379,808 $ 440,467 Interest rate swaps CAD $ 196,988 $ — Undesignated Derivative Instruments Interest rate swaps USD $ 275,424 $ 272,716 Interest rate cap USD $ — $ 42,102 Energy derivative MWh 1,707,350 2,211,563 Foreign currency forward contracts CAD $ 62,300 $ —
Derivative Instruments, Gain (Loss)	The following table presents gains and losses on derivative contracts designated and qualifying as cash flow hedges recognized in accumulated other comprehensive loss, as well as amounts reclassified to earnings for the following periods (in thousands): Year Ended December 31, Description 2015 2014 2013 Gains (losses) recognized in accumulated OCI Effective portion of change in fair value $ (16,163 ) $ (33,444 ) $ 24,932 Gains (losses) reclassified from accumulated OCI into: Interest expense Derivative settlements $ 12,234 $ 13,774 $ 11,943 Realized loss on designated derivatives, net Termination of derivatives $ 11,221 $ — $ — Loss (gain) on undesignated derivatives, net De-designation of derivatives $ 5,918 $ — $ — Gains (losses) recognized in interest expense Ineffective portion $ (809 ) $ — $ —
Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location	The following table presents gains and losses on derivatives not designated as hedges (in thousands): Year Ended December 31, Derivative Type Financial Statement Line Item Description 2015 2014 2013 Interest rate derivatives (Loss) gain on undesignated derivatives, net Change in fair value, net of settlements $ (5,758 ) (1) $ (11,668 ) $ 15,601 Interest rate derivatives (Loss) gain on undesignated derivatives, net Derivative settlements $ (4,838 ) $ (4,075 ) $ (2,099 ) Energy derivative Electricity sales Change in fair value, net of settlements $ (792 ) $ (3,878 ) $ (11,272 ) Energy derivative Electricity sales Derivative settlements $ 20,568 $ 13,525 $ 16,798 Foreign currency forward contracts (Loss) gain on undesignated derivatives, net Change in fair value, net of settlements $ 4,110 $ — $ — Foreign currency forward contracts (Loss) gain on undesignated derivatives, net Derivative settlements $ 996 $ — $ — (1) Amount includes the reclassification of $5.9 million from accumulated other comprehensive loss related to the dedesignation of certain interest rate derivative instruments at Spring Valley.

Accumulated Other Comprehensi41

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Summary of Accumulated Other Comprehensive (Loss) Income	The following table summarizes changes in the accumulated other comprehensive loss balance, net of tax, by component: Foreign Currency Effective Portion of Change in Fair Value of Derivatives Proportionate Share of Equity Investee's OCI Total Balances at December 31, 2012 $ (154 ) $ (43,877 ) $ (1,475 ) $ (45,506 ) Other comprehensive (loss) income before reclassifications (8,309 ) 24,932 2,473 19,096 Amounts reclassified from accumulated other comprehensive loss — 11,943 — 11,943 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 ) Other comprehensive loss before reclassifications (10,875 ) (33,444 ) (5,991 ) (50,310 ) Amounts reclassified from accumulated other comprehensive loss — 13,774 — 13,774 Net current period other comprehensive loss (10,875 ) (19,670 ) (5,991 ) (36,536 ) Balances at December 31, 2014 $ (19,338 ) $ (26,672 ) $ (7,903 ) $ (53,913 ) Other comprehensive loss before reclassifications (28,947 ) (16,163 ) (6,640 ) (51,750 ) Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives — 17,139 — 17,139 Amounts reclassified from accumulated other comprehensive loss — 12,234 2,412 14,646 Net current period other comprehensive (loss) income (28,947 ) 13,210 (4,228 ) (19,965 ) Balances at December 31, 2015 $ (48,285 ) $ (13,462 ) $ (12,131 ) $ (73,878 ) Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015 — (553 ) — (553 ) Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015 $ (48,285 ) $ (12,909 ) $ (12,131 ) $ (73,325 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
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): December 31, 2015 Level 1 Level 2 Level 3 Total Assets Interest rate swaps $ — $ 559 $ — $ 559 Energy derivative — — 63,683 63,683 Foreign currency forward contracts — 4,110 — 4,110 $ — $ 4,669 $ 63,683 $ 68,352 Liabilities Interest rate swaps $ — $ 43,002 $ — $ 43,002 Energy derivative — — — — Foreign currency forward contracts — — — — $ — $ 43,002 $ — $ 43,002 December 31, 2014 Level 1 Level 2 Level 3 Total Assets Interest rate swaps $ — $ 3,048 $ — $ 3,048 Interest rate cap — 352 — 352 Energy derivative — — 64,475 64,475 $ — $ 3,400 $ 64,475 $ 67,875 Liabilities Interest rate swaps $ — $ 33,774 $ — $ 33,774 $ — $ 33,774 $ — $ 33,774
Reconciliation of Contingent Liabilities and Energy Derivative Contract Measured at Fair Value	The following table presents a reconciliation of the energy derivative contract measured at fair value on a recurring basis using significant unobservable inputs (in thousands): 2015 2014 Balance at beginning of year $ 64,475 $ 68,353 Total gains (losses) included in electricity sales 19,776 9,646 Settlements (20,568 ) (13,524 ) Balance at end of year $ 63,683 $ 64,475
Schedule of Valuation Techniques and Significant Unobservable Inputs Used in Level 3 Fair Value Measurements	The valuation techniques and significant unobservable inputs used in recurring Level 3 fair value measurements were as follows (in thousands, for fair value): December 31, 2015 Fair Value Valuation Technique Significant Unobservable Inputs Range Energy derivative $63,683 Discounted cash flow Forward electricity prices $12.48 - $74.94 (1) Discount rate 0.61% - 1.46% December 31, 2014 Fair Value Valuation Technique Significant Unobservable Inputs Range Energy derivative $64,475 Discounted cash flow Forward electricity prices $14.24 - $106.11 (1) Discount rate 0.26% - 1.63% (1) Represents price per MWh
Carrying Amounts and Fair Values of Company's Financial Liabilities	The following table presents the carrying amount and fair value 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, 2015 and 2014 , but for which fair value is disclosed (in thousands): Fair Value As reflected on the balance sheet Level 1 Level 2 Level 3 Total December 31, 2015 Convertible senior notes $ 197,362 $ — $ 189,863 $ — $ 189,863 Long-term debt, including current portion $ 1,218,524 $ — $ 1,192,286 $ — $ 1,192,286 December 31, 2014 Long-term debt, including current portion $ 1,413,858 $ — $ 1,416,744 $ — $ 1,416,744

Income Taxes Income Taxes (Tabl

Income Taxes Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 2014 2013 Current: Federal $ — $ — $ — State — — — Foreign 489 182 — Total current expense 489 182 — Deferred: Federal — — 2,961 State — — — Foreign 4,454 2,954 1,585 Total deferred expense 4,454 2,954 4,546 Total provision for income taxes $ 4,943 $ 3,136 $ 4,546
Domestic and Foreign Components of Net Income (Loss) Before Income Tax (Benefit) Expense	The following table presents the domestic and foreign components of net (loss) income before income tax provision (in thousands): Year ended December 31, 2015 2014 2013 U.S. $ (66,883 ) $ (34,788 ) $ 4,022 Foreign 16,219 (2,075 ) 10,596 Total $ (50,664 ) $ (36,863 ) $ 14,618
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 following periods: Year ended December 31, 2015 2014 2013 Computed tax at statutory rate 35.0 % 35.0 % 35.0 % Adjustment for income in non-taxable entities allocable to noncontrolling interest (13.0 )% (7.6 )% 16.5 % Foreign rate differential Tax rate differential on pre-tax book income, other (6.6 )% 5.6 % 2.1 % Local tax on branch profits/(losses)—Puerto Rico 0.3 % 1.6 % 13.1 % Permanent book/tax differences (domestic only) (0.1 )% (0.1 )% (2.2 )% Valuation allowance (25.1 )% (33.4 )% 187.2 % Chilean shareholder benefit due to tax regime change 0.4 % (3.6 )% — % Change in tax rate due to change in Chilean tax regime — % (6.2 )% — % Other (0.7 )% 0.1 % 3.1 % ARRA Section 1603 grant-basis reduction deferred tax assets — % — % (223.7 )% Effective income tax rate (9.8 )% (8.6 )% 31.1 %
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 follows (in thousands): Year ended December 31, 2015 2014 Deferred tax assets / (liabilities) — current: Accruals, prepaids and other deferred tax assets and liabilities $ — $ (344 ) Basis difference in derivatives — 4,779 Total gross deferred tax assets / (liabilities) — current — 4,435 Less: valuation allowance — (4,266 ) Total net deferred tax assets / (liabilities) — current $ — $ 169 Deferred tax assets/(liabilities) — non-current: (1) Accruals, prepaids and other deferred tax assets and liabilities $ 1,525 $ — Basis difference in derivatives 3,187 — Property, plant and equipment (175,527 ) (104,767 ) Basis difference in foreign subsidiaries 104 37,626 Partnership interest 34,664 994 Hatchet Ridge financing 27,096 28,044 Asset retirement obligation 4,970 5,216 Unrealized loss on derivatives 305 — Other temporary differences — 256 Other deferred tax assets and liabilities (7,125 ) (5,081 ) Net operating loss carryforwards 224,194 130,248 Tax credits 4,421 — Total gross deferred tax assets/(liabilities) — non-current (1) $ 117,814 $ 92,536 Less: valuation allowance (133,193 ) (107,480 ) Total net deferred tax assets / (liabilities) — non-current (1) $ (15,379 ) $ (14,944 ) Total net deferred tax assets/(liabilities ) (1) $ (15,379 ) $ (14,775 ) (1) Presented in accordance with prospective adoption of ASU 2015-17, "Income Taxes: Balance Sheet Classification of Deferred Taxes." See Note 2 , Summary of Significant Accounting Policies - Recently Issued Accounting Standards , for additional information.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Noncontrolling Interests By Project [Table Text Block]	The following table presents the balances for noncontrolling interests by project and the Company's respective ownership percentage (in thousands, except percentages). See Note 3, Acquisitions , for additional information. Noncontrolling Ownership Percentage December 31, December 31, 2015 2014 2015 2014 Gulf Wind $ — $ 97,061 — % 60 % El Arrayán 34,224 35,624 30 % 30 % Logan's Gap 190,397 — 18 % N/A Panhandle 1 195,791 205,333 21 % 21 % Panhandle 2 184,773 192,568 19 % 19 % Post Rock 196,346 — 40 % N/A Amazon Wind Farm Fowler Ridge 142,731 — 35 % N/A Noncontrolling interest $ 944,262 $ 530,586
Schedule of Dividends Declared	Dividends Per Share Declaration Date Record Date Payment Date 2015: Fourth Quarter $ 0.3720 October 29, 2015 December 31, 2015 January 29, 2016 Third Quarter $ 0.3630 July 21, 2015 September 30, 2015 October 30, 2015 Second Quarter $ 0.3520 April 20, 2015 June 30, 2015 July 30, 2015 First Quarter $ 0.3420 February 24, 2015 March 31, 2015 April 30, 2015
Schedule of Noncontrolling Interest	The following table presents the components of total noncontrolling interest as reported in stockholders’ equity in the consolidated balance sheets by project (in thousands). See Note 3, Acquisitions , for additional information. Capital Accumulated Income (Loss) Accumulated Other Comprehensive Loss Noncontrolling Interest Balances at December 31, 2013 $ 90,217 $ 18,601 $ (9,024 ) $ 99,794 Contribution from noncontrolling interests 406,163 — — 406,163 Fair value of noncontrolling interest in El Arrayán 35,259 — — 35,259 Distribution to noncontrolling interests (2,100 ) — — (2,100 ) Net loss — (8,709 ) — (8,709 ) Other comprehensive income, net of tax — — 179 179 Balances at December 31, 2014 529,539 9,892 (8,845 ) 530,586 Acquisition of Post Rock 205,100 — — 205,100 Buyout of noncontrolling interests (88,747 ) (14,244 ) 7,944 (95,047 ) Contributions from noncontrolling interests 334,231 — — 334,231 Distributions to noncontrolling interests (7,882 ) — — (7,882 ) Net loss — (23,074 ) — (23,074 ) Other comprehensive income, net of tax — — 348 348 Balances at December 31, 2015 $ 972,241 $ (27,426 ) $ (553 ) $ 944,262

Equity Incentive Award Plan (Ta

Equity Incentive Award Plan (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Weighted Average Assumptions	The following weighted average assumptions were used: Year Ended Risk-free interest rate 1.68% Expected life (in years) 5.8 Expected volatility 36% Expected dividend yield 5.7%
Summary of Stock Option Activity	The following table summarizes stock option activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Exercise Price Weighted Average Remaining Contractual Life Aggregate Intrinsic Value Outstanding at December 31, 2014 429,962 $ 22.00 Exercised — 22.00 Forfeited or expired — 22.00 Outstanding at December 31, 2015 429,962 $ 22.00 7.8 $ — (1) Exercisable at December 31, 2015 318,670 $ 22.00 7.8 $ — (1) Vested and expected to vest, net of estimated forfeitures at December 31, 2015 429,962 $ 22.00 7.8 $ — (1) (1) Closing stock price on December 31, 2015 is lower than the stock option exercise price.
Summary of Restricted Stock Awards Activity	The following table summarizes RSU activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Grant-Date Nonvested at December 31, 2014 — N/A Granted 22,772 $ 25.94 Vested (22,772) $ 25.94 Forfeited — N/A Repurchased for employee tax withholding — N/A Nonvested at December 31, 2015 — N/A The following table summarizes TSR-RSAs activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Grant-Date Nonvested at December 31, 2014 — N/A Granted 85,268 $ 39.16 Vested — N/A Forfeited — N/A Repurchased for employee tax withholding — N/A Nonvested at December 31, 2015 85,268 $ 39.16 The following table summarizes RSA activity under the 2013 Plan for the year ended December 31, 2015 : Shares Weighted-Average Grant-Date Nonvested at December 31, 2014 118,015 $ 25.29 Granted 100,868 $ 29.58 Vested (65,189) $ 26.23 Forfeited — N/A Repurchased for employee tax withholding (30,826) $ 27.67 Nonvested at December 31, 2015 122,868 $ 27.71

Loss Per Share (Tables)

Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Computations of Basic and Diluted Earnings (Loss) per Share	The computations for Class A basic and diluted loss per share are as follows (in thousands except share data): Year ended December 31, 2015 2014 2013 Numerator for basic and diluted loss per share: Net loss attributable to Pattern Energy $ (32,533 ) $ (31,290 ) $ (13,336 ) Less: dividends declared on Class A common shares (102,861 ) (56,976 ) (11,103 ) Less: deemed dividends on Class B common shares — (21,901 ) — Less: earnings allocated to participating securities (32 ) — — Undistributed loss attributable to common stockholders $ (135,426 ) $ (110,167 ) $ (24,439 ) Denominator for loss per share: Weighted average number of shares: Class A common stock - basic and diluted 70,535,568 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 $ 1.46 $ 1.34 $ 0.31 Undistributed loss (1.92 ) (1.90 ) (0.48 ) Basic loss per share $ (0.46 ) $ (0.56 ) $ (0.17 ) Class A common stock: Diluted loss per share $ (0.46 ) $ (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 ) Dividends declared per Class A common share $ 1.43 $ 1.30 $ 0.31 Deemed dividends per Class B common share $ — $ 1.41 $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Contractual Obligation, Fiscal Year Maturity Schedule	estimates of future commitments related to the various agreements that the Company has entered into (in thousands): 2016 2017 2018 2019 2020 Thereafter Total Purchase, construction and other commitments $ 20,661 $ 1,419 $ 563 $ 554 $ 591 $ 5,605 $ 29,393 Operating leases 11,103 12,069 14,156 14,637 14,811 285,977 352,753 Service and maintenance agreements 56,802 51,668 40,936 34,149 31,556 146,981 362,092 Total commitments $ 88,566 $ 65,156 $ 55,655 $ 49,340 $ 46,958 $ 438,563 $ 744,238

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Allocated Costs Included in Combined Statement of Operations	The following table presents net bilateral management service cost reimbursements included in the consolidated statements of operations (in thousands): Year Ended December 31, 2015 2014 2013 Project expense $ — $ — $ 1,995 Related party general and administrative 7,589 5,787 $ 8,169 Related party income (2,665 ) (2,612 ) $ (665 ) Other (expense) income, net — — $ (551 ) Total $ 4,924 $ 3,175 $ 8,948

Selected Quarterly Financial 49

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Summary of Quarterly Consolidated Statements of Operations	Quarterly financial data in thousands, except per share data: Three months ended December 31, September 30, June 30, March 31, 2015 2015 2015 2015 Revenue $ 90,597 $ 89,697 $ 84,671 $ 64,866 Gross profit $ 16,674 $ 22,250 $ 22,348 $ 10,564 Net (loss) income $ (3,873 ) $ (35,332 ) $ 5,657 $ (22,059 ) Net loss attributable to noncontrolling interest $ (6,327 ) $ (5,927 ) $ (8,660 ) $ (2,160 ) Net income (loss) attributable to Pattern Energy $ 2,454 $ (29,405 ) $ 14,317 $ (19,899 ) Basic and diluted earnings (loss) per share—Class A common stock $ 0.03 $ (0.40 ) $ 0.21 $ (0.30 ) Cash dividends declared per Class A common share $ 0.37 $ 0.36 $ 0.35 $ 0.34 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 income (loss) attributable to noncontrolling interest $ 4,406 $ (2,073 ) $ (4,032 ) $ (7,010 ) Net (loss) income attributable to Pattern Energy $ (20,392 ) $ (7,208 ) $ 11,199 $ (14,889 ) Basic (loss) earnings per share—Class A common stock $ (0.36 ) $ (0.15 ) $ 0.17 $ (0.20 ) Diluted (loss) earnings per share—Class A common stock $ (0.36 ) $ (0.15 ) $ 0.16 $ (0.29 ) Basic and diluted (loss) earnings 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 per Class B common share $ 0.46 $ 0.46 $ 0.48 $ —

Organization (Detail)

Organization (Detail)	Oct. 02, 2013shares	Dec. 31, 2015USD ($)shares	Dec. 31, 2014USD ($)shares	Dec. 31, 2013USD ($)	Oct. 01, 2013USD ($)	Feb. 09, 2015	May. 14, 2014	May. 13, 2014	Sep. 24, 2013shares	Oct. 17, 2012shares
Schedule Of Description Of Business [Line Items]
Common stock, shares authorized		500,000,000	500,000,000
Preferred Stock, shares authorized		100,000,000
Common stock conversion basis		all of the outstanding Class B common stock automatically converted, on a one-for-one basis, into Class A shares. There were no other conversion rights attached to Class B common stock.
Prior period expense of entity | $		$ 37,396,000	$ 28,320,000	$ 12,988,000
Class B Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Common stock conversion basis		one-to-one
Pattern Development [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)						25.00%	35.00%	63.00%
Pattern Development [Member] | Class A Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock (shares)	19,445,000
Shares issues, percent of outstanding shares	63.00%
Pattern Development [Member] | Class B Common Stock [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock (shares)	15,555,000
Pattern Renewables LP [Member]
Schedule Of Description Of Business [Line Items]
Issuance of common stock (shares)										100
Pattern Energy Group Inc. [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)										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
Common stock conversion ratio			1
Hatchet Ridge [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
St Josephs [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Spring Valley [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Santa Isabel [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Ocotillo [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Amazon Wind Farm Fowler Ridge [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Gulf Wind [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Lost Creek [Member]
Schedule Of Description Of Business [Line Items]
Ownership interest (percent)		100.00%
Pattern Energy Unconsolidated [Member] | Maximum [Member]
Schedule Of Description Of Business [Line Items]
Prior period expense of entity | $					$ 10,000

Summary of Significant Accoun51

Summary of Significant Accounting Policies - Change in Estimate of Depreciable Lives (Details) - USD ($) $ / shares in Units, $ in Thousands

3 Months Ended

9 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2013

Oct. 01, 2013

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Change in Accounting Estimate [Line Items]

Depreciation

$ 141,200

$ 102,900

$ 82,000

Net (loss) income

$ (3,873)

$ (35,332)

$ 5,657

$ (22,059)

$ (15,986)

$ (9,281)

$ 7,167

$ (21,899)

$ (19,533)

$ 29,605

$ (55,607)

$ (39,999)

$ 10,072

Class A Common Stock [Member]

Change in Accounting Estimate [Line Items]

Basic and diluted loss per share (in dollars per share)

$ 0.03

$ (0.40)

$ 0.21

$ (0.30)

Wind Farms Constructed After 2011 [Member]

Change in Accounting Estimate [Line Items]

Property, plant and equipment useful lives (in years)

25 years

Other Wind Farms [Member]

Change in Accounting Estimate [Line Items]

Property, plant and equipment useful lives (in years)

20 years

As Previously Reported [Member] | Wind Farms Constructed After 2011 [Member]

Change in Accounting Estimate [Line Items]

Property, plant and equipment useful lives (in years)

20 years

Service Life [Member]

Change in Accounting Estimate [Line Items]

Change in accounting estimate

The Company periodically reviews the estimated economic useful lives of its fixed assets. In 2015, based on technical review of various wind farm characteristics, the expected economic useful lives of certain wind farms were longer than the estimated economic useful lives used for depreciation purposes in the Company’s financial statements. As a result, effective January 1, 2015, the Company changed its estimate of the economic useful lives of wind farms for which construction began after 2011, from 20 to 25 years. All other wind farms continue to depreciate over an estimated economic useful life of 20 years.

Depreciation

$ (14,700)

Net (loss) income

$ 13,900

Service Life [Member] | Class A Common Stock [Member]

Change in Accounting Estimate [Line Items]

Basic and diluted loss per share (in dollars per share)

$ (0.09)

Service Life [Member] | Wind Farms Constructed After 2011 [Member]

Change in Accounting Estimate [Line Items]

Property, plant and equipment useful lives (in years)

25 years

Service Life [Member] | As Previously Reported [Member] | Wind Farms Constructed After 2011 [Member]

Change in Accounting Estimate [Line Items]

Property, plant and equipment useful lives (in years)

20 years

Summary of Significant Accoun52

Summary of Significant Accounting Policies - Reclassifications (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective portion of change in fair market value of derivatives	$ (16,163)	$ (33,444)	$ 24,932
Reclassifications to net loss	(12,234)	(13,774)	(11,943)
Effective portion of change in fair market value of derivatives	(1,740)	(3,422)	3,184
Reclassifications to net loss attributable to noncontrolling interest	2,088	3,601	1,904
Deferred finance costs, net	26,303	36,755
Accounting Standards Update 2015-03 [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member] | Other Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred finance costs, net	(26,300)	(36,800)
Accounting Standards Update 2015-03 [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member] | Long-term Debt [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred finance costs, net	26,300	36,800
Accounting Standards Update 2015-03 [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member] | Long-Term Debt, Current [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred finance costs, net	$ (3,700)	(11,900)
Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective portion of change in fair market value of derivatives		(27,500)	(23,900)
Reclassifications to net loss		27,500	23,900
Effective portion of change in fair market value of derivatives		(7,200)	(3,800)
Reclassifications to net loss attributable to noncontrolling interest		$ 7,200	$ 3,800

Summary of Significant Accoun53

Summary of Significant Accounting Policies - Schedule of Significant Customers (Detail) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue [Member] | San Diego Gas and Electric [Member]
Concentration Risk [Line Items]
Concentrations of credit risk (percent)	17.07%	22.09%	16.31%
Revenue [Member] | PREPA [Member]
Concentration Risk [Line Items]
Concentrations of credit risk (percent)	8.42%	9.29%	8.21%
Trade Receivables [Member] | San Diego Gas and Electric [Member]
Concentration Risk [Line Items]
Concentrations of credit risk (percent)	17.03%	14.13%	26.21%
Trade Receivables [Member] | PREPA [Member]
Concentration Risk [Line Items]
Concentrations of credit risk (percent)	8.80%	6.91%	16.88%

Summary of Significant Accoun54

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015
Significant Accounting Policies [Line Items]
Asset impairment charges		$ 0.4
Maximum tax benefit likely to be realized upon ultimate settlement, percentage		50.00%
Power purchase agreement [Member]
Significant Accounting Policies [Line Items]
Remaining term of amortizable intangible assets (in years)	15 years	14 years
Remaining term of amortizable intangible liabilities (in years)	17 years	17 years
Minimum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives (in years)		2 years
Minimum [Member] | Easements land option and mining rights agreements [Member]
Significant Accounting Policies [Line Items]
Term of estimated useful lives (in years)		5 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives (in years)		5 years
Maximum [Member] | Easements land option and mining rights agreements [Member]
Significant Accounting Policies [Line Items]
Term of estimated useful lives (in years)		25 years
Wind Farm [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives (in years)		20 years
Wind Farms Constructed After 2011 [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives (in years)		25 years

Summary of Significant Accoun55

Summary of Significant Accounting Policies - Geographical Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 90,597	$ 89,697	$ 84,671	$ 64,866	$ 79,418	$ 71,519	$ 65,007	$ 49,549	$ 329,831	$ 265,493	$ 201,573
Property, Plant and Equipment, net (including Construction in Progress)	3,294,620				2,377,051				3,294,620	2,377,051
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									258,542	201,408	161,505
Property, Plant and Equipment, net (including Construction in Progress)	2,791,259				1,810,414				2,791,259	1,810,414
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									39,178	46,593	40,068
Property, Plant and Equipment, net (including Construction in Progress)	184,115				233,690				184,115	233,690
Chile [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									32,111	17,492	$ 0
Property, Plant and Equipment, net (including Construction in Progress)	$ 319,246				$ 332,947				$ 319,246	$ 332,947

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail)

Dec. 18, 2015USD ($)

Jul. 30, 2015USD ($)

Jul. 28, 2015USD ($)

Jun. 17, 2015USD ($)MW

May. 15, 2015USD ($)MW

Apr. 29, 2015USD ($)MW

Dec. 19, 2014USD ($)MW

Nov. 10, 2014USD ($)MW

Jun. 30, 2014USD ($)MW

Jun. 25, 2014USD ($)MW

Nov. 30, 2015USD ($)

Dec. 31, 2015USD ($)

Mar. 31, 2015USD ($)

Jun. 25, 2014USD ($)

Sep. 30, 2014USD ($)

Dec. 31, 2015USD ($)

Dec. 31, 2014USD ($)

Dec. 31, 2013USD ($)

Jun. 30, 2015

Feb. 09, 2015

Jun. 24, 2014

May. 14, 2014

May. 13, 2014

Business Acquisition [Line Items]

Contingent obligations payable

$ 2,156,000

$ 2,156,000

$ 4,000,000

Contingent liabilities paid

515,000

0

$ 0

Carrying value of investment

116,473,000

116,473,000

29,079,000

Buyout of noncontrolling interests

$ 86,276,000

K2 [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

33.33%

Business acquisition price

$ 128,000,000

$ 132,400,000

Contingent obligations incurred

4,000,000

Capitalized transaction costs

400,000

Assumed long-term debt, net of financing costs

$ 221,800,000

PPA of project (in years)

20 years

20 years

Excess of investment balance over equity in net assets

$ 115,600,000

K2 [Member] | Property, Plant and Equipment [Member]

Business Acquisition [Line Items]

Excess of investment balance over equity in net assets

61,900,000

Power purchase agreement [Member] | K2 [Member]

Business Acquisition [Line Items]

Excess of investment balance over equity in net assets

53,700,000

Pattern Development [Member]

Business Acquisition [Line Items]

Ownership interest (percent)

25.00%

35.00%

63.00%

Pattern Development [Member] | K2 [Member]

Business Acquisition [Line Items]

Business acquisition price

$ 128,400,000

132,400,000

Power generation capacity | MW

270

Contingent obligations incurred

$ 4,000,000

Post Rock Wind Project [Member]

Business Acquisition [Line Items]

Ownership interest (percent)

100.00%

Lost Creek Wind Finco LLC [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Lost Creek Wind Finco LLC [Member] | Lost Creek Wind Project [Member]

Business Acquisition [Line Items]

Power generation capacity | MW

150

Linco In County Wind Project Holdco Llc [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Linco In County Wind Project Holdco Llc [Member] | Post Rock Wind Project [Member]

Business Acquisition [Line Items]

Power generation capacity | MW

201

Linco In County Wind Project Holdco Llc [Member] | Post Rock Wind Project [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Lost Creek Finco and Lincoln County Holdco [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 242,000,000

Lost Creek And Post Rock [Member]

Business Acquisition [Line Items]

Valuation adjustment of acquired property, plant and equipment

2,000,000

Valuation adjustment of acquired other assets

(2,300,000)

Valuation adjustment of acquired asset retirement obligations and other accrued liabilities

200,000

Valuation adjustment of acquired current derivative liabilities

(500,000)

Transaction related expenses

$ 1,700,000

Assumed long-term debt, net of financing costs

$ 108,838,000

Lost Creek Wind Holdco LLC [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 35,200,000

Lost Creek Wind Holdco LLC [Member] | Class A Members [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Lost Creek Wind Project [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Post Rock Wind Power Project LLC [Member] | Class A Members [Member]

Business Acquisition [Line Items]

Distribution percentage to members prior to earlier of flip point or November 20, 2023

40.00%

Distribution percentage to members prior to earlier of flip point or November 20, 2027

60.00%

Distribution percentage to members November 20, 2027 and prior to flip point

100.00%

Distribution percentage to members after flip point

10.00%

Allocation percentage of tax items prior to flip point

99.00%

Allocation percentage of tax items after flip point

10.00%

Allocation percentage of tax items attributable to liquidation of derivative contracts

4.95%

Post Rock Wind Power Project LLC [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Allocation percentage of tax items prior to flip point

1.00%

Allocation percentage of tax items attributable to liquidation of derivative contracts

95.05%

Logan's Gap [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 15,100,000

Transaction related expenses

$ 100,000

300,000

Contingent obligations payable

$ 7,975,000

1,700,000

1,700,000

Valuation adjustment of prepaid expenses and other current assets

$ 100,000

Valuation adjustment of deferred financing costs

800,000

Valuation adjustment of construction in progress

100,000

Valuation adjustment of accrued construction costs

$ 900,000

Contingent liabilities paid

$ 6,300,000

Logan's Gap [Member] | Tax Equity Investors [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

18.00%

Logan's Gap [Member] | Pattern Development [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 15,100,000

Power generation capacity | MW

164

Logan's Gap [Member] | Class A Members [Member]

Business Acquisition [Line Items]

Distribution percentage to members after flip point

5.10%

Allocation percentage of tax items prior to flip point

99.00%

Distribution percentage to members prior to earlier of flip point or December 17, 2024

18.00%

Logan's Gap [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Allocation percentage of tax items prior to flip point

1.00%

Allocation percentage of tax items after flip point

5.10%

Logan's Gap [Member] | Pattern Energy [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

82.00%

Panhandle 2 [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 123,800,000

Power generation capacity | MW

182

Transaction related expenses

200,000

$ 600,000

Panhandle 2 [Member] | Tax Equity Investors [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

19.00%

Panhandle 2 [Member] | Class A Members [Member]

Business Acquisition [Line Items]

Distribution percentage to members after flip point

5.00%

Allocation percentage of tax items prior to flip point

99.00%

Distribution percentage to members prior to earlier of flip point or November 30, 2023

19.00%

Distribution percentage to members if distributions are below a determined schedule

40.00%

Panhandle 2 [Member] | Class A Members [Member] | Tax Equity Investors [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Panhandle 2 [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Allocation percentage of tax items prior to flip point

1.00%

Allocation percentage of tax items after flip point

5.00%

Panhandle 2 [Member] | Pattern Energy [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

81.00%

Panhandle 2 [Member] | Pattern Energy [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Panhandle 1 [Member]

Business Acquisition [Line Items]

Power generation capacity | MW

218

Transaction related expenses

500,000

Ownership interest In project's distributable cash flow (percent)

79.00%

Panhandle 1 [Member] | Tax Equity Investors [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

21.00%

Panhandle 1 [Member] | Pattern Development [Member]

Business Acquisition [Line Items]

Business acquisition price

$ 124,400,000

Power generation capacity | MW

218

Panhandle 1 [Member] | Class A Members [Member]

Business Acquisition [Line Items]

Distribution percentage to members after flip point

5.00%

Allocation percentage of tax items prior to flip point

99.00%

Distribution percentage to members prior to earlier of flip point or June 29, 2023

21.00%

Panhandle 1 [Member] | Class A Members [Member] | Tax Equity Investors [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Panhandle 1 [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Allocation percentage of tax items prior to flip point

1.00%

Allocation percentage of tax items after flip point

5.00%

Panhandle 1 [Member] | Class B Members [Member] | Pattern Development [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

AEI El Arrayan [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

100.00%

Business acquisition price

$ 45,300,000

El Arrayan [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

38.50%

38.50%

Ownership interest (percent)

70.00%

70.00%

Business acquisition price

$ 45,300,000

Power generation capacity | MW

115

Transaction related expenses

400,000

Indirect interest (percentage)

31.50%

31.50%

31.50%

Fair value of equity interest at acquisition date

$ 37,000,000

Implied equity value

117,500,000

$ 117,500,000

Carrying value of investment

$ 19,100,000

19,100,000

Net gain on transactions

17,900,000

Nonrecurring gain excluded from pro forma net loss

$ 17,900,000

Net loss in equity earnings

$ 400,000

El Arrayan [Member] | Majority control [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

70.00%

70.00%

Lost Creek, Post Rock, Logan's Gap, Panhandle 2, Panhandle 1, and El Arrayán [Member]

Business Acquisition [Line Items]

Transaction related expenses

$ 1,800,000

$ 2,900,000

Gulf Wind [Member]

Business Acquisition [Line Items]

Ownership interest (percent)

100.00%

Business acquisition price

$ 72,800,000

Buyout of noncontrolling interests

$ 17,200,000

Gulf Wind [Member] | Pattern Development [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

27.00%

Business acquisition price

$ 13,000,000

MetLife Capital Limited Partnership [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Fowler RidgeIv Wind Farm Llc [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 37,500,000

Power generation capacity | MW

150

Transaction related expenses

$ 600,000

Valuation adjustment of construction in progress

$ 100,000

Contingent liabilities paid

$ 27,200,000

Business acquisition, contingent payment possible

$ 29,100,000

Business acquisition, fixed portion of contingent payment possible

25,100,000

Business acquisition, variable portion of contingent payment possible

4,000,000

Contingent obligations incurred

$ 14,800,000

Fowler RidgeIv Wind Farm Llc [Member] | Power purchase agreement [Member]

Business Acquisition [Line Items]

Percentage of gross revenue allocated to third party

1.00%

Gross revenue allocated to third party

$ 2,500,000

Period of allocation of gross revenue to third party (in years)

13 years

Fowler RidgeIv Wind Farm Llc [Member] | Close of Construction Financing [Member]

Business Acquisition [Line Items]

Contingent obligations incurred

$ 5,000,000

Fowler RidgeIv Wind Farm Llc [Member] | Commissioning of First Wind Turbine at Project [Member]

Business Acquisition [Line Items]

Contingent obligations incurred

7,300,000

Fowler RidgeIv Wind Farm Llc [Member] | Energization of Project Substation [Member]

Business Acquisition [Line Items]

Contingent obligations incurred

2,500,000

Fowler RidgeIv Wind Farm Llc [Member] | Maximum [Member]

Business Acquisition [Line Items]

Business acquisition, contingent payment possible

$ 29,100,000

Fowler RidgeIv Wind Farm Llc [Member] | Tax Equity Investors [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

35.00%

Fowler RidgeIv Wind Farm Llc [Member] | Pattern Development [Member]

Business Acquisition [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 37,500,000

Power generation capacity | MW

150

Transaction related expenses

$ 600,000

Contingent liabilities paid

$ 27,200,000

Fowler RidgeIv Wind Farm Llc [Member] | Class A Members [Member]

Business Acquisition [Line Items]

Distribution percentage to members after flip point

5.00%

Allocation percentage of tax items prior to flip point

99.00%

Distribution percentage to members prior to earlier of flip point or November 30, 2025

35.00%

Fowler RidgeIv Wind Farm Llc [Member] | Class B Members [Member]

Business Acquisition [Line Items]

Allocation percentage of tax items prior to flip point

1.00%

Allocation percentage of tax items after flip point

5.00%

Fowler RidgeIv Wind Farm Llc [Member] | Pattern Energy [Member]

Business Acquisition [Line Items]

Ownership interest In project's distributable cash flow (percent)

65.00%

Acquisitions - Schedule of Asse

Acquisitions - Schedule of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	May. 15, 2015	Apr. 29, 2015	Dec. 31, 2014	Dec. 19, 2014	Nov. 10, 2014	Jun. 30, 2014	Jun. 25, 2014
Business Acquisition [Line Items]
Current portion of contingent liabilities	$ (2,156)			$ (4,000)
Lost Creek And Post Rock [Member]
Business Acquisition [Line Items]
Cash and cash equivalents		$ 3,501
Restricted cash, current		11,787
Trade receivables		7,910
Prepaid expenses		1,232
Other current assets		444
Restricted cash, non-current		4,592
Property, plant and equipment		543,347
Finite-lived intangible assets		97,400
Other assets		17,632
Accounts payable and other accrued liabilities		(2,611)
Accrued interest		(951)
Derivative liabilities, current		(3,759)
Short-term debt		(7,463)
Finite-lived intangible liabilities		(60,300)
Asset retirement obligations		(7,192)
Long-term debt, net of financing costs		(108,838)
Derivative liabilities		(14,631)
Total consideration		482,100
Less: temporary equity		(35,000)
Less: noncontrolling interests		(205,100)
Total consideration after temporary equity and noncontrolling interests		$ 242,000
Logan's Gap [Member]
Business Acquisition [Line Items]
Cash and cash equivalents					$ 2
Restricted cash, current					5,003
Prepaid expenses and other current assets					1,790
Deferred financing costs, current					2,882
Construction in progress					23,821
Property, plant and equipment					116
Other assets					80
Accrued construction costs					(5,617)
Current portion of contingent liabilities	$ (1,700)				(7,975)
Related party payable					(5,003)
Total consideration					$ 15,099
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)
Short-term debt						(195,351)
Asset retirement obligations						(2,003)
Related party payable						(121)
Total consideration						$ 123,830
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)
Asset retirement obligations							(2,557)
Related party payable							(44)
Total consideration							334,650
Less: noncontrolling interests							(210,250)
Total consideration after non-controlling interest							$ 124,400
El 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
Finite-lived 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)
Short-term debt								(16,586)
Asset retirement obligations								(2,354)
Long-term debt, net of financing costs								(209,295)
Derivative liabilities, non-current								(501)
Net deferred tax liabilities								(13,001)
Total consideration								117,536
Less: noncontrolling interests								(35,259)
Total consideration after non-controlling interest								$ 82,277
Fowler RidgeIv Wind Farm Llc [Member]
Business Acquisition [Line Items]
Prepaid expenses and other current assets			$ 1,753
Deferred financing costs, current			2,132
Turbine advances			4,000
Construction in progress			34,487
Finite-lived intangible assets			2,247
Accrued construction costs			(6,549)
Total consideration			$ 38,070

Acquisitions - Schedule of Supp

Acquisitions - Schedule of Supplemental Pro Forma Data (Detail) - Lost Creek, Post Rock, Logan's Gap, Panhandle 2, Panhandle 1, and El Arrayán [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Pro forma total revenue	$ 351,094	$ 326,094
Pro forma total expenses	411,746	389,180
Pro forma net loss	(60,652)	(63,086)
Less: pro forma net loss attributable to noncontrolling interest	(29,091)	(21,591)
Pro forma net loss attributable to Pattern Energy	$ (31,561)	$ (41,495)

Acquisitions - Schedule of Amou

Acquisitions - Schedule of Amounts Included in Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended									9 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Total revenue	$ 90,597	$ 89,697	$ 84,671	$ 64,866	$ 79,418	$ 71,519	$ 65,007	$ 49,549			$ 329,831	$ 265,493	$ 201,573
Total expenses											37,396	28,320	12,988
Net loss	(3,873)	(35,332)	5,657	(22,059)	(15,986)	(9,281)	7,167	(21,899)	$ (19,533)	$ 29,605	(55,607)	(39,999)	10,072
Net loss attributable to noncontrolling interest	(6,327)	(5,927)	(8,660)	(2,160)	4,406	(2,073)	(4,032)	(7,010)			(23,074)	(8,709)	(6,887)
Net (loss) income attributable to Pattern Energy	$ 2,454	$ (29,405)	$ 14,317	$ (19,899)	$ (20,392)	$ (7,208)	$ 11,199	$ (14,889)	$ (13,336)	$ 30,295	(32,533)	$ (31,290)	$ 16,959
Lost Creek And Post Rock [Member]
Business Acquisition [Line Items]
Total revenue											31,093
Total expenses											34,574
Net loss											(3,481)
Net loss attributable to noncontrolling interest											(5,114)
Net (loss) income attributable to Pattern Energy											$ 1,633

Property, Plant and Equipment -

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 3,703,781	$ 2,629,147
Less: accumulated depreciation	(409,161)	(278,291)
Property, plant and equipment, net	3,294,620	2,350,856
Operating wind farms [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	3,700,140	2,624,640
Furniture, fixtures and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	3,500	4,366
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 141	$ 141

Property, Plant and Equipment61

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Depreciation expense related to property, plant and equipment	$ 141.2	$ 102.9	$ 82
Cash grant received	253.4
Decrease in depreciation expense	$ 11.4	$ 12.7	$ 13

Finite-Lived Intangible Asset62

Finite-Lived Intangible Assets and Liability - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Power purchase agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization expense	$ 4,100,000
Intangible liability, amortization expense	(2,200,000)
Other intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization expense	$ (100,000)	$ (200,000)	$ 0

Finite-Lived Intangible Asset63

Finite-Lived Intangible Assets and Liability - Schedule of Major Components of the Finite-Lived Intangible Assets and Liability (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets, Gross		$ 102,079
Finite lived intangible assets, Accumulated Amortization		(4,357)	$ (154)
Finite lived intangible assets, Net		97,722	1,257
Finite lived intangible liability, Accumulated Amortization		2,168	0
Finite lived intangible liability, Net		$ (58,132)	$ 0
Power purchase agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining term of amortizable intangible assets (in years)	15 years	14 years
Remaining term of amortizable intangible liabilities (in years)	17 years	17 years
Finite lived intangible assets, Gross		$ 97,400
Finite lived intangible assets, Accumulated Amortization		(4,114)
Finite lived intangible assets, Net		93,286
Finite lived intangible liability, Gross		(60,300)
Finite lived intangible liability, Accumulated Amortization		2,168
Finite lived intangible liability, Net		$ (58,132)
Other intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining term of amortizable intangible assets (in years)		17 years	17 years
Finite lived intangible assets, Gross		$ 4,679	$ 1,411
Finite lived intangible assets, Accumulated Amortization		(243)	(154)
Finite lived intangible assets, Net		$ 4,436	$ 1,257

Finite-Lived Intangible Asset64

Finite-Lived Intangible Assets and Liability - Schedule of Estimated Future Amortization Expense (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Power purchase agreement [Member]
Finite-Lived Intangible Assets [Line Items]
2,016	$ 3,049
2,017	3,031
2,018	3,031
2,019	3,031
2,020	3,049
Thereafter	19,963
Other intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
2,016	277
2,017	352
2,018	277
2,019	277
2,020	277
Thereafter	$ 2,976

Unconsolidated Investments - Ad

Unconsolidated Investments - Additional Information (Detail)	Jun. 17, 2015	Dec. 31, 2015	Jun. 25, 2014
El Arrayan [Member]
Schedule of Equity Method Investments [Line Items]
Equity interest in acquiree percentage			70.00%
South Kent [Member]
Schedule of Equity Method Investments [Line Items]
PPA of project (in years)		20 years
Grand [Member]
Schedule of Equity Method Investments [Line Items]
PPA of project (in years)		20 years
K2 [Member]
Schedule of Equity Method Investments [Line Items]
PPA of project (in years)	20 years	20 years

Unconsolidated Investments - Sc

Unconsolidated Investments - Schedule of Projects Accounted under Equity Method of Accounting (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	$ 116,473	$ 29,079
South Kent [Member]
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	$ 6,185	$ 17,360
Ownership interest (percent)	50.00%	50.00%
Grand [Member]
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	$ 5,735	$ 11,719
Ownership interest (percent)	45.00%	45.00%
K2 [Member]
Schedule of Equity Method Investments [Line Items]
Unconsolidated investments	$ 104,553	$ 0
Ownership interest (percent)	33.30%

Unconsolidated Investments - Su

Unconsolidated Investments - Summary of Aggregated Balance Sheets and Operating Results (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
K2 [Member]
Schedule of Equity Method Investments [Line Items]
Current assets	$ 46,342
Non-current assets	631,151
Total assets	677,493
Current liabilities	46,901
Non-current liabilities	617,460
Total liabilities	664,361
Total equity	13,132
Total liabilities and equity	677,493
Revenue	52,130
Cost of revenue	18,450
Operating expenses	3,140
Other expense	10,061
Net (loss) income	$ 20,479
El Arrayan [Member]
Schedule of Equity Method Investments [Line Items]
Revenue		$ 1,821	$ 0
Cost of revenue		1,060	15
Operating expenses		682	900
Other expense		1,341	26
Net (loss) income		$ (1,262)	$ (941)

Accounts Payable and Other Ac68

Accounts Payable and Other Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accounts payable	$ 625	$ 673
Other accrued liabilities	9,583	7,892
Warranty settlement payments	0	639
LTSA/PPE upgrades liability	4,909	680
Turbine operations and maintenance payable	985	1,310
Purchase agreement obligations	5,749	0
Land lease rent payable	2,513	2,115
Spare-parts inventory payables	1,181	0
Payroll liabilities	5,345	4,453
Property tax payable	11,145	4,625
Sales tax payable	741	2,406
Accounts payable and other accrued liabilities	$ 42,776	$ 24,793

Revolving Credit Facility (Deta

Revolving Credit Facility (Details) - USD ($)	Nov. 15, 2012	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Line of Credit Facility [Line Items]
Revolving credit facility amount outstanding		$ 355,000,000	$ 50,000,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility	$ 120,000,000	$ 500,000,000	350,000,000	$ 145,000,000
Term (in years)	4 years
Additional borrowing capacity available through accordion feature	$ 35,000,000
Commitment fee percentage		0.50%
Revolving credit facility amount outstanding		$ 355,000,000	50,000,000
Letters-of-credit outstanding		$ 27,200,000	$ 45,100,000
Revolving Credit Facility [Member] | Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Basis spread on interest rate (percent)		0.50%
Revolving Credit Facility [Member] | Eurodollar Rate [Member]
Line of Credit Facility [Line Items]
Basis spread on interest rate (percent)		1.00%
Revolving Credit Facility [Member] | Eurodollar Rate [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Margin on interest rate (percent)		1.25%
Revolving Credit Facility [Member] | Eurodollar Rate [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Margin on interest rate (percent)		1.75%
Revolving Credit Facility [Member] | LIBOR [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Basis spread on interest rate (percent)		2.25%
Revolving Credit Facility [Member] | LIBOR [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Basis spread on interest rate (percent)		2.75%

Long Term Debt - Schedule of Lo

Long Term Debt - Schedule of Long Term Debt (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Nov. 16, 2015	Oct. 20, 2015	Jul. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 1,243,447				$ 1,450,613
Debt Instrument, Unamortized Premium	1,380				0
Unamortized financing costs	(26,303)				(36,755)
Debt, Current	(44,144)				(109,693)
Long term debt, noncurrent	1,174,380				1,304,165
Unamortized financing costs, current	3,671				11,868
El Arrayan EKF team loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 107,160				109,630
Contractual Interest Rate (percent)	5.56%
Effective Interest Rate (percent)	5.56%
Long term debt, Maturity	March 2,029
St. Joseph term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0				189,472
Contractual Interest Rate (percent)	5.88%	5.95%
Effective Interest Rate (percent)	5.95%
Long term debt, Maturity	May 2,031
Santa Isabel term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 109,973				112,609
Contractual Interest Rate (percent)	4.57%
Effective Interest Rate (percent)	4.57%
Long term debt, Maturity	September 2,033
Logan's Gap construction loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0				58,691
Contractual Interest Rate (percent)	1.57%
Effective Interest Rate (percent)	1.57%
Long term debt, Maturity	December 2,015
Gulf Wind term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0			$ 154,100	156,122
Contractual Interest Rate (percent)	3.28%
Effective Interest Rate (percent)	6.59%
Long term debt, Maturity	March 2,020
Ocotillo commercial term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 208,119				222,175
Contractual Interest Rate (percent)	2.3567%
Effective Interest Rate (percent)	3.77%
Long term debt, Maturity	August 2,020
Change in margin on interest rate (percent)	1.00%
Lost Creek term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 110,846				0
Contractual Interest Rate (percent)	2.19%
Effective Interest Rate (percent)	6.49%
Long term debt, Maturity	September 2,027
El Arrayan commercial term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 97,418				99,665
Contractual Interest Rate (percent)	3.1739%
Effective Interest Rate (percent)	5.65%
Long term debt, Maturity	March 2,029
Spring Valley term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 132,670		$ 133,200		167,261
Unamortized financing costs			$ (5,000)
Contractual Interest Rate (percent)	2.3567%
Effective Interest Rate (percent)	4.89%
Long term debt, Maturity	June 2,030
Ocotillo development term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 104,500				106,700
Contractual Interest Rate (percent)	2.7067%
Effective Interest Rate (percent)	4.37%
Long term debt, Maturity	August 2,033
St Joseph term loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 158,181				0
Contractual Interest Rate (percent)	2.455%
Effective Interest Rate (percent)	3.84%
Long term debt, Maturity	November 2,033
Hatchet Ridge financing lease obligation [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 214,580				$ 228,288
Contractual Interest Rate (percent)	1.43%
Effective Interest Rate (percent)	1.43%
Long term debt, Maturity	December 2,032

Long Term Debt - Summary of Pri

Long Term Debt - Summary of Principal Payments Due under Long Term Debt (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Debt Disclosure [Abstract]
2,016	$ 47,613
2,017	51,705
2,018	60,438
2,019	66,304
2,020	69,526
Thereafter	947,861
Long term debt	$ 1,243,447

Long Term Debt - Schedule of Re

Long Term Debt - Schedule of Reconciliation of Interest Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Disclosure [Abstract]
Interest and commitment fees incurred	$ 70,847	$ 59,864	$ 57,478
Capitalized interest, commitment fees, and letter of credit fees	(6,607)	(2,856)	(4,210)
Letter of credit fees incurred	4,572	4,377	3,530
Amortization of debt discount/premium, net	1,660	0	0
Amortization of financing costs	7,435	6,309	6,816
Interest expense	$ 77,907	$ 67,694	$ 63,614

Long Term Debt - Additional Inf

Long Term Debt - Additional Information (Detail)

Nov. 17, 2015CAD

Oct. 20, 2015USD ($)

Oct. 19, 2015

Sep. 03, 2015USD ($)

Sep. 02, 2015

Jul. 30, 2015USD ($)

Nov. 15, 2012USD ($)

May. 31, 2012USD ($)

Dec. 31, 2010

Dec. 31, 2015USD ($)

Dec. 31, 2014USD ($)

Dec. 31, 2013USD ($)

Nov. 16, 2015CAD

Jul. 28, 2015

Apr. 29, 2015USD ($)

Debt Instrument [Line Items]

Long-term Debt

$ 1,243,447,000

Early extinguishment of debt

(4,941,000)

$ 0

$ 0

Outstanding

1,243,447,000

1,450,613,000

Unamortized financing costs

26,303,000

36,755,000

Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Credit agreement

$ 120,000,000

500,000,000

350,000,000

145,000,000

Letters-of-credit outstanding

$ 27,200,000

45,100,000

Term (in years)

4 years

St. Joseph term loan [Member]

Debt Instrument [Line Items]

Long-term Debt | CAD

CAD 219,000,000

CAD 212,529,945

Credit agreement | CAD

244,000,000

Interest rate (percent)

5.88%

5.95%

Letters-of-credit outstanding | CAD

CAD 25,000,000

Percentage of interest rate set by interest rate swaps

90.00%

Interest rate set by swap (percent)

4.00%

Annual increase in interest rate set by swap (percent)

0.125%

Period of increases to interest rate set by swap (in years)

3 years

Early extinguishment of debt

$ (800,000)

Outstanding

$ 0

189,472,000

St. Joseph term loan [Member] | CDOR [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

1.625%

Basis spread on variable rate increase (percent)

0.125%

Basis spread on variable rate increase period (in years)

3 years

Spring Valley term loan [Member]

Debt Instrument [Line Items]

Interest rate (percent)

2.3567%

Repayments of debt

$ 29,700,000

Outstanding

133,200,000

$ 132,670,000

167,261,000

Amendment fees

900,000

Unamortized financing costs

$ 5,000,000

Spring Valley term loan [Member] | LIBOR [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

1.75%

2.375%

Basis spread on variable rate increase (percent)

0.125%

0.25%

Basis spread on variable rate increase period (in years)

4 years

4 years

Logan's Gap construction loan [Member]

Debt Instrument [Line Items]

Credit agreement

282,800,000

Interest rate (percent)

1.57%

Outstanding

$ 0

58,691,000

Construction loan facility

$ 0

247,100,000

Logan's Gap construction loan [Member] | Letter of Credit Facility [Member]

Debt Instrument [Line Items]

Credit agreement

35,700,000

Lost Creek term loan [Member]

Debt Instrument [Line Items]

Interest rate (percent)

2.19%

Outstanding

$ 110,846,000

0

Amendment fees

$ 1,500,000

Lost Creek term loan [Member] | LIBOR [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

1.65%

2.75%

Basis spread on variable rate increase (percent)

0.125%

0.25%

Basis spread on variable rate increase period (in years)

4 years

Third party legal and other fees

$ 700,000

Lost Creek term loan [Member] | Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Credit agreement

$ 10,700,000

Gulf Wind term loan [Member]

Debt Instrument [Line Items]

Interest rate (percent)

3.28%

Early extinguishment of debt

$ (4,100,000)

Outstanding

$ 154,100,000

$ 0

156,122,000

Voting interest acquired (percent)

100.00%

Percentage of outstanding balance prepaid

100.00%

Fowler RidgeIv Wind Farm Llc [Member]

Debt Instrument [Line Items]

Construction loan facility

$ 0

Fowler RidgeIv Wind Farm Llc [Member] | Construction Loans [Member]

Debt Instrument [Line Items]

Credit agreement

$ 199,100,000

Interest rate (percent)

1.69%

Fowler RidgeIv Wind Farm Llc [Member] | Letter of Credit Facility [Member]

Debt Instrument [Line Items]

Letters-of-credit outstanding

$ 22,500,000

Letter of Credit, Reimbursement and Loan Agreement [Member] | REC Agreements [Member]

Debt Instrument [Line Items]

Letters-of-credit outstanding

11,200,000

Letter of Credit, Reimbursement and Loan Agreement [Member] | Power purchase agreement [Member]

Debt Instrument [Line Items]

Letters-of-credit outstanding

$ 11,300,000

El Arrayan Credit Agreement [Member]

Debt Instrument [Line Items]

Credit agreement

$ 225,000,000

El Arrayan Credit Agreement [Member] | Letter of Credit Facility [Member]

Debt Instrument [Line Items]

Credit agreement

15,000,000

El Arrayan Credit Agreement [Member] | Commercial Tranche [Member]

Debt Instrument [Line Items]

Credit agreement

$ 100,000,000

Percentage debt hedged

95.80%

El Arrayan Credit Agreement [Member] | Commercial Tranche [Member] | LIBOR [Member] | Closing until the sixth anniversary of closing [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

2.75%

El Arrayan Credit Agreement [Member] | Commercial Tranche [Member] | LIBOR [Member] | Sixth anniversary to the tenth anniversary of closing [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

3.00%

El Arrayan Credit Agreement [Member] | Commercial Tranche [Member] | LIBOR [Member] | Tenth anniversary to the fourteenth anniversary of closing [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

3.25%

El Arrayan Credit Agreement [Member] | Commercial Tranche [Member] | LIBOR [Member] | After the fourteenth anniversary of closing [Member]

Debt Instrument [Line Items]

Basis spread on interest rate (percent)

3.50%

El Arrayan Credit Agreement [Member] | El Arrayan EKF team loan [Member]

Debt Instrument [Line Items]

Credit agreement

$ 110,000,000

Interest rate (percent)

5.56%

El Arrayan Credit Agreement [Member] | El Arrayan EKF team loan [Member] | Sixth anniversary to the tenth anniversary of closing [Member]

Debt Instrument [Line Items]

Margin on interest rate (percent)

0.25%

El Arrayan Credit Agreement [Member] | El Arrayan EKF team loan [Member] | Tenth anniversary to the fourteenth anniversary of closing [Member]

Debt Instrument [Line Items]

Margin on interest rate (percent)

0.50%

El Arrayan Credit Agreement [Member] | El Arrayan EKF team loan [Member] | After the fourteenth anniversary of closing [Member]

Debt Instrument [Line Items]

Margin on interest rate (percent)

0.75%

Hatchet Ridge Term Loan [Member]

Debt Instrument [Line Items]

Interest rate (percent)

1.43%

Outstanding

$ 214,580,000

228,288,000

Term (in years)

22 years

Payments of financing lease obligations

$ 16,900,000

$ 15,000,000

$ 14,800,000

Long Term Debt - Convertible Se

Long Term Debt - Convertible Senior Note (Details)	Jul. 31, 2015USD ($)day$ / shares	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Sep. 30, 2015USD ($)
Debt Instrument [Line Items]
Unamortized financing costs		$ (5,014,000)	$ 0
Carrying value of convertible senior notes		197,362,000	0
Amortization of financing costs		7,435,000	6,309,000	$ 6,816,000
Amortization of debt discount		1,660,000	$ 0	$ 0
Convertible Debt [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued	$ 225,000,000	225,000,000
Interest rate (percent)	4.00%
Conversion ratio (shares per dollar of debt)	0.0354925
Conversion price (in dollars per share) | $ / shares	$ 28.175
Dividend threshold trigger (in dollars per share) | $ / shares	$ 0.363
Repurchase requirement, percentage of principal balance	100.00%
Discount rate (percent)	6.60%
Principal	$ 225,000,000	225,000,000
Unamortized debt discount		22,624,000
Unamortized financing costs		(5,014,000)
Carrying value of convertible senior notes		197,362,000
Carrying value of the equity component		23,743,000
Equity issuance costs					$ 700,000
Contractual coupon interest		3,800,000
Amortization of financing costs		500,000
Amortization of debt discount		$ 1,800,000
Convertible Debt [Member] | Conversion Option One [Member]
Debt Instrument [Line Items]
Threshold trading days | day	20
Threshold consecutive trading days	30 days
Threshold stock price trigger (percentage)	130.00%
Convertible Debt [Member] | Conversion Option Two [Member]
Debt Instrument [Line Items]
Threshold trading days | day	5
Threshold consecutive trading days	10 days
Conversion threshold, Principal amount used to calculate trading price per principal amount	$ 1,000
Conversion threshold, Trading price per principal amount (percent)	98.00%

Asset Retirement Obligation - A

Asset Retirement Obligation - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Asset Retirement Obligations [Line Items]
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 the end of its estimated economic useful life. Effective January 1, 2015, the Company changed its estimate of the useful lives of wind farms for which construction began after 2011, from 20 years to 25 years.
Adjustment related to change in useful life	$ 1,907	$ 0
Wind Farms Constructed After 2011 [Member]
Asset Retirement Obligations [Line Items]
Property, plant and equipment useful lives (in years)	25 years
As Previously Reported [Member] | Wind Farms Constructed After 2011 [Member]
Asset Retirement Obligations [Line Items]
Property, plant and equipment useful lives (in years)	20 years

Asset Retirement Obligation - R

Asset Retirement Obligation - Reconciliation of Aggregate Carrying Amounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning asset retirement obligations	$ 29,272	$ 20,834
Net additions during the year	13,189	7,195
Foreign currency translation adjustment	(411)	(228)
Adjustment related to change in useful life	(1,907)	0
Accretion expense	2,054	1,471
Ending asset retirement obligations	$ 42,197	$ 29,272

Derivative Instruments - Schedu

Derivative Instruments - Schedule of Derivative Instruments Classified as Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Fair Market Value, Assets Current	$ 24,338	$ 18,506
Fair Market Value, Assets Long-Term	44,014	49,369
Fair Market Value, Liabilities Current	14,343	16,307
Fair Market Value, Liabilities Long-Term	28,659	17,467
Designated as Hedging Instrument [Member] | Interest rate swaps [Member]
Derivative [Line Items]
Fair Market Value, Assets Current	0	0
Fair Market Value, Assets Long-Term	0	525
Fair Market Value, Liabilities Current	10,034	12,904
Fair Market Value, Liabilities Long-Term	24,360	17,467
Undesignated Derivative Instruments [Member] | Interest rate swaps [Member]
Derivative [Line Items]
Fair Market Value, Assets Current	0	0
Fair Market Value, Assets Long-Term	559	2,523
Fair Market Value, Liabilities Current	4,309	3,403
Fair Market Value, Liabilities Long-Term	4,299	0
Undesignated Derivative Instruments [Member] | Interest rate cap [Member]
Derivative [Line Items]
Fair Market Value, Assets Current		0
Fair Market Value, Assets Long-Term		352
Fair Market Value, Liabilities Current		0
Fair Market Value, Liabilities Long-Term		0
Undesignated Derivative Instruments [Member] | Energy derivative [Member]
Derivative [Line Items]
Fair Market Value, Assets Current	20,856	18,506
Fair Market Value, Assets Long-Term	42,827	45,969
Fair Market Value, Liabilities Current	0	0
Fair Market Value, Liabilities Long-Term	0	$ 0
Undesignated Derivative Instruments [Member] | Foreign currency forward [Member]
Derivative [Line Items]
Fair Market Value, Assets Current	3,482
Fair Market Value, Assets Long-Term	628
Fair Market Value, Liabilities Current	0
Fair Market Value, Liabilities Long-Term	$ 0

Derivative Instruments - Notion

Derivative Instruments - Notional Amount of Outstanding Derivatives (Details) CAD in Thousands, $ in Thousands	Dec. 31, 2015USD ($)MW	Dec. 31, 2015CADMW	Dec. 31, 2014USD ($)MW	Dec. 31, 2014CADMW	Dec. 31, 2010MW
Designated as Hedging Instrument [Member] | Interest rate swaps [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 379,808	CAD 196,988	$ 440,467	CAD 0
Undesignated Derivative Instruments [Member] | Interest rate swaps [Member]
Derivative [Line Items]
Derivative, Notional Amount	275,424		272,716
Undesignated Derivative Instruments [Member] | Interest rate cap [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 0		$ 42,102
Undesignated Derivative Instruments [Member] | Energy derivative [Member]
Derivative [Line Items]
Energy Derivative, Notional Amount | MW	1,707,350	1,707,350	2,211,563	2,211,563	504,220
Undesignated Derivative Instruments [Member] | Foreign currency forward [Member]
Derivative [Line Items]
Derivative, Notional Amount | CAD		CAD 62,300		CAD 0

Derivative Instruments - Summar

Derivative Instruments - Summary of Effects of Cash Flow Hedges on Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI, Effective portion	$ (16,163)	$ (33,444)	$ 24,932
Interest expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated OCI into Income, Effective portion	12,234	13,774	11,943
Gains (losses) reclassified from accumulated OCI into Income, Ineffective portion	(809)	0	0
Realized loss on designated derivatives, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated OCI into Income, Effective portion	11,221	0	0
Loss (gain) on undesignated derivatives, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated OCI into Income, Effective portion	$ 5,918	$ 0	$ 0

Derivative Instruments - Summ80

Derivative Instruments - Summary of Effects of Undesignated Derivatives on Consolidated Statement of Operations (Details) - USD ($) $ in Thousands	Oct. 20, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Not Designated as Hedging Instrument [Member] | Change in Fair Value [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on interest rate derivatives		$ (5,758)	$ (11,668)	$ 15,601
Not Designated as Hedging Instrument [Member] | Change in Fair Value [Member] | Energy derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on energy derivatives		(792)	(3,878)	(11,272)
Not Designated as Hedging Instrument [Member] | Change in Fair Value [Member] | Foreign currency forward [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on foreign currency forward contracts		4,110	0	0
Not Designated as Hedging Instrument [Member] | Derivative Settlements [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on interest rate derivatives		(4,838)	(4,075)	(2,099)
Not Designated as Hedging Instrument [Member] | Derivative Settlements [Member] | Energy derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on energy derivatives		20,568	13,525	16,798
Not Designated as Hedging Instrument [Member] | Derivative Settlements [Member] | Foreign currency forward [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on foreign currency forward contracts		$ 996	$ 0	$ 0
Spring Valley term loan [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated OCI into Income, Effective portion	$ 5,900

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Detail) $ in Thousands	Oct. 20, 2015USD ($)	Jul. 28, 2015USD ($)	Dec. 31, 2015USD ($)MW	Dec. 31, 2010MW	Jul. 30, 2015USD ($)	Dec. 31, 2014USD ($)MW
Derivative [Line Items]
Accumulated other comprehensive loss will be reclassified into earnings over the next twelve months			$ 10,000
Outstanding			$ 1,243,447			$ 1,450,613
Interest rate swaps [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Minimum remaining maturity period (in months and in years)			141 months
Maximum remaining maturity period (in months and in years)			249 months
Interest rate swaps [Member] | Undesignated Derivative Instruments [Member]
Derivative [Line Items]
Minimum remaining maturity period (in months and in years)			63 months
Maximum remaining maturity period (in months and in years)			174 months
Foreign currency forward [Member]
Derivative [Line Items]
Minimum remaining maturity period (in months and in years)			1 month
Maximum remaining maturity period (in months and in years)			18 months
Energy derivative [Member] | Undesignated Derivative Instruments [Member]
Derivative [Line Items]
Energy Derivative, Notional Amount | MW			1,707,350	504,220		2,211,563
Spring Valley term loan [Member]
Derivative [Line Items]
Repayments of debt	$ 29,700
Outstanding	133,200		$ 132,670			$ 167,261
Gains (losses) reclassified from accumulated OCI into Income, Effective portion	$ (5,900)
Gulf Wind term loan [Member]
Derivative [Line Items]
Outstanding			$ 0		$ 154,100	$ 156,122
Gains (losses) reclassified from accumulated OCI into Income, Effective portion		$ 11,200
Loss on termination of derivative		$ 200
Gulf Wind [Member] | Interest rate cap [Member]
Derivative [Line Items]
Term of debt expected to be refinanced (in years)				10 years
Interest rate cap protection percentage				6.00%

Accumulated Other Comprehensi82

Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	$ 569,828	$ 589,412	$ 1,164,734	$ 568,004	$ 589,412
Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives			12,234	13,774	11,943
Net current period other comprehensive (loss) income	6,847	24,192	(19,965)	(36,536)	31,039
Ending Balance	568,004	569,828	1,775,762	1,164,734	568,004
Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015			944,262	530,586
Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015			831,500	634,148
Foreign Currency [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance		(154)	(19,338)	(8,463)	(154)
Other comprehensive (loss) income before reclassifications			(28,947)	(10,875)	(8,309)
Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives			0
Amounts reclassified from accumulated other comprehensive loss			0	0	0
Net current period other comprehensive (loss) income			(28,947)	(10,875)	(8,309)
Grand acquisition					0
Ending Balance	(8,463)		(48,285)	(19,338)	(8,463)
Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015			0
Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015			(48,285)
Effective Portion of Change in Fair Value of Derivatives [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance		(43,877)	(26,672)	(7,002)	(43,877)
Other comprehensive (loss) income before reclassifications			(16,163)	(33,444)	24,932
Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives			17,139
Amounts reclassified from accumulated other comprehensive loss			12,234	13,774	11,943
Net current period other comprehensive (loss) income			13,210	(19,670)	36,875
Grand acquisition					0
Ending Balance	(7,002)		(13,462)	(26,672)	(7,002)
Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015			(553)
Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015			(12,909)
Proportionate Share of Equity Investee's OCI [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance		(1,475)	(7,903)	(1,912)	(1,475)
Other comprehensive (loss) income before reclassifications			(6,640)	(5,991)	2,473
Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives			0
Amounts reclassified from accumulated other comprehensive loss			2,412	0	0
Net current period other comprehensive (loss) income			(4,228)	(5,991)	2,473
Grand acquisition					(2,910)
Ending Balance	(1,912)		(12,131)	(7,903)	(1,912)
Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015			0
Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015			(12,131)
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance		$ (45,506)	(53,913)	(17,377)	(45,506)
Other comprehensive (loss) income before reclassifications			(51,750)	(50,310)	19,096
Amounts reclassified from accumulated other comprehensive loss due to termination/de-designation of interest rate derivatives			17,139
Amounts reclassified from accumulated other comprehensive loss			14,646	13,774	11,943
Net current period other comprehensive (loss) income			(19,965)	(36,536)	31,039
Grand acquisition					(2,910)
Ending Balance	$ (17,377)		(73,878)	$ (53,913)	$ (17,377)
Less: accumulated other comprehensive loss attributable to noncontrolling interest, December 31, 2015			(553)
Accumulated other comprehensive loss attributable to Pattern Energy, December 31, 2015			$ (73,325)

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Required Fair Value Measurement on Recurring Basis (Detail) - Recurring Measurement Basis [Member] - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	$ 68,352	$ 67,875
Derivative Liability	43,002	33,774
Interest rate swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	559	3,048
Derivative Liability	43,002	33,774
Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	63,683	64,475
Derivative Liability	0
Interest rate cap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset		352
Foreign currency forward [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	4,110
Derivative Liability	0
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0	0
Derivative Liability	0	0
Level 1 [Member] | Interest rate swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0	0
Derivative Liability	0	0
Level 1 [Member] | Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0	0
Derivative Liability	0
Level 1 [Member] | Interest rate cap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset		0
Level 1 [Member] | Foreign currency forward [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0
Derivative Liability	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	4,669	3,400
Derivative Liability	43,002	33,774
Level 2 [Member] | Interest rate swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	559	3,048
Derivative Liability	43,002	33,774
Level 2 [Member] | Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0	0
Derivative Liability	0
Level 2 [Member] | Interest rate cap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset		352
Level 2 [Member] | Foreign currency forward [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	4,110
Derivative Liability	0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	63,683	64,475
Derivative Liability	0	0
Level 3 [Member] | Interest rate swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0	0
Derivative Liability	0	0
Level 3 [Member] | Energy derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	63,683	64,475
Derivative Liability	0
Level 3 [Member] | Interest rate cap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset		$ 0
Level 3 [Member] | Foreign currency forward [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0
Derivative Liability	$ 0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Changes in Level 3 Assets and Liabilities (Detail) - Energy derivative [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Unrealized losses recognized	$ (800)	$ (3,900)	$ (11,300)
Recurring Measurement Basis [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of year	64,475	68,353
Total gains (losses) included in electricity sales	19,776	9,646
Settlements	(20,568)	(13,524)
Balance at end of year	$ 63,683	$ 64,475	$ 68,353

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Level 3 Inputs, Quantitative Information (Details) - Energy derivative [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Minimum [Member] | Discounted Cash Flow [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Forward electricity price (in dollars per Mwh)	12.48	14.24
Discount rate (percent)	0.61%	0.26%
Maximum [Member] | Discounted Cash Flow [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Forward electricity price (in dollars per Mwh)	74.94	106.11
Discount rate (percent)	1.46%	1.63%
Level 3 [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Derivative Asset	$ 63,683	$ 64,475

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Amounts and Fair Values of Financial Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes	$ 197,362	$ 0
Long-term debt, including current portion	1,243,447
As reflected on the balance sheet [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes	197,362
Long-term debt, including current portion	1,218,524	1,413,858
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes	189,863
Long-term debt, including current portion	1,192,286	1,416,744
Fair Value [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes	0
Long-term debt, including current portion	0	0
Fair Value [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes	189,863
Long-term debt, including current portion	1,192,286	1,416,744
Fair Value [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible senior notes	0
Long-term debt, including current portion	$ 0	$ 0

Income Taxes - Components of Ta

Income Taxes - Components of Tax Provision (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ 0	$ 0	$ 0
State	0	0	0
Foreign	489	182	0
Total current expense	489	182	0
Deferred:
Federal	0	0	2,961
State	0	0	0
Foreign	4,454	2,954	1,585
Total deferred expense	4,454	2,954	4,546
Total provision for income taxes	$ 4,943	$ 3,136	$ 4,546

Income Taxes - Components of In

Income Taxes - Components of Income Before Income Tax (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
U.S.	$ (66,883)	$ (34,788)	$ 4,022
Foreign	16,219	(2,075)	10,596
Total	$ (50,664)	$ (36,863)	$ 14,618

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Statutory Rate to Effective Rate (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Computed tax at statutory rate (percent)	35.00%	35.00%	35.00%
Adjustment for income in non-taxable entities allocable to noncontrolling interest (percent)	(13.00%)	(7.60%)	16.50%
Tax rate differential on pre-tax book income, other (percent)	(6.60%)	5.60%	2.10%
Local tax on branch profits/(losses)—Puerto Rico (percent)	0.30%	1.60%	13.10%
Permanent book/tax differences (domestic only) (percent)	(0.10%)	(0.10%)	(2.20%)
Valuation allowance (percent)	(25.10%)	(33.40%)	187.20%
Chilean shareholder benefit due to tax regime change (percent)	0.40%	(3.60%)	0.00%
Change in tax rate due to change in Chilean tax regime (percent) (percent)	0.00%	(6.20%)	0.00%
Other (percent)	(0.70%)	0.10%	3.10%
ARRA Section 1603 grant-basis reduction deferred tax assets (percent)	(0.00%)	(0.00%)	(223.70%)
Effective income tax rate (percent)	(9.80%)	(8.60%)	31.10%

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets / (liabilities) — current:
Accruals, prepaids and other deferred tax assets and liabilities	$ 0	$ (344)
Basis difference in derivatives	0	4,779
Total gross deferred tax assets / (liabilities) — current	0	4,435
Less: valuation allowance	0	(4,266)
Total net deferred tax assets / (liabilities) — current	0	169
Deferred tax assets/(liabilities) — non-current:
Accruals, prepaids and other deferred tax assets and liabilities	1,525	0
Basis difference in derivatives	3,187	0
Property, plant and equipment	175,527	104,767
Basis difference in foreign subsidiaries	104	37,626
Partnership interest	34,664	994
Hatchet Ridge financing	27,096	28,044
Asset retirement obligation	4,970	5,216
Unrealized loss on derivatives	305	0
Other temporary differences	0	256
Other deferred tax assets and liabilities	(7,125)	(5,081)
Net operating loss carryforwards	224,194	130,248
Tax credits	4,421	0
Total gross deferred tax assets/(liabilities) — non-current	117,814	92,536
Less: valuation allowance	(133,193)	(107,480)
Total net deferred tax assets / (liabilities) — non-current	(15,379)	(14,944)
Total net deferred tax assets/(liabilities)	$ (15,379)	$ (14,775)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
Net change in valuation allowance	$ 21.4	$ 11.8
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 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.
Special tax rate related to tax holiday (percent)	4.00%
Income tax holiday, termination date	for a 15 year period and is scheduled to terminate on December 31, 2026
Duration of tax holiday (in years)	15 years
Tax holiday impact, decrease in foreign deferred tax expense	$ (0.4)
Class A Common Stock [Member]
Income Taxes [Line Items]
Tax holiday impact on net income per share of basic and diluted (in dollars per share)	$ 0.005
Domestic [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 503.6
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 66

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands

Jul. 28, 2015USD ($)shares

Feb. 09, 2015USD ($)shares

Oct. 02, 2013USD ($)Projectshares

Dec. 31, 2015$ / sharesshares

Sep. 30, 2015$ / shares

Jun. 30, 2015$ / shares

Mar. 31, 2015$ / shares

Dec. 31, 2014$ / sharesshares

Sep. 30, 2014$ / shares

Jun. 30, 2014$ / shares

Mar. 31, 2014$ / shares

Dec. 31, 2015USD ($)$ / sharesshares

Dec. 31, 2014USD ($)$ / sharesshares

Dec. 31, 2013USD ($)$ / shares

Feb. 08, 2015

May. 14, 2014

May. 13, 2014

Changes In Equity And Comprehensive Income Line Items [Line Items]

Proceeds from public offering, net of issuance costs | $

$ 317,432

$ 286,757

$ 317,926

Common stock conversion basis

all of the outstanding Class B common stock automatically converted, on a one-for-one basis, into Class A shares. There were no other conversion rights attached to Class B common stock.

Common stock voting rights

Holders of the Company’s Class A 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. On February 9, 2015, Pattern Development's interest in the Company was reduced to 25% causing it to no longer be eligible to certain approval rights pursuant to Shareholder Approval Rights Agreement.

Preferred stock, authorized

100,000,000

100,000,000

Preferred stock, issued

0

0

0

0

Preferred stock, outstanding

0

0

0

0

Pattern Development [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Payments to acquire businesses | $

$ 232,600

Wind power projects | Project

8

Equity interest in company percentage

25.00%

35.00%

35.00%

63.00%

Pattern Development [Member] | Gulf Wind [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Ownership interest (percent)

40.00%

40.00%

Pattern Development [Member] | Distributable Cash Flow Of Gulf Wind [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Ownership interest (percent)

27.00%

Pattern Development [Member] | Asset under Construction [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Wind power projects | Project

2

Pattern Development [Member] | Power Generation [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Wind power projects | Project

6

Pattern Energy [Member] | Distributable Cash Flow Of Gulf Wind [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Ownership interest (percent)

40.00%

Corporate Joint Venture [Member] | Gulf Wind [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Ownership interest (percent)

33.00%

Parent Company [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Proceeds from public offering, net of issuance costs | $

$ 317,432

$ 286,757

$ 317,926

Class A Common Stock [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Issuance of common stock, shares

5,435,000

12,000,000

Proceeds from Issuance of Common Stock | $

$ 120,800

$ 196,200

Dividends declared (in dollars per share) | $ / shares

$ 0.3720

$ 0.3630

$ 0.3520

$ 0.342

$ 0.34

$ 0.33

$ 0.32

$ 0.31

$ 1.43

$ 1.30

$ 0.31

Dividend declared date

Oct. 29, 2015

Jul. 21, 2015

Apr. 20, 2015

Feb. 24, 2015

Dividend payment, date of stockholders record

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dividend payable date

Jan. 29, 2016

Oct. 30, 2015

Jul. 30, 2015

Apr. 30, 2015

Class A Common Stock [Member] | Pattern Development [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Issuance of common stock, shares

5,000,000

19,445,000

Class A Common Stock [Member] | Parent Company [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Issuance of common stock, shares

7,000,000

Class B Common Stock [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Common stock conversion basis

one-to-one

Class B Common Stock [Member] | Pattern Development [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Issuance of common stock, shares

15,555,000

IPO [Member] | Class A Common Stock [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Issuance of common stock, shares

16,000,000

Proceeds from public offering, net of issuance costs | $

$ 317,000

Over-Allotment Option [Member] | Class A Common Stock [Member] | Underwriters [Member]

Changes In Equity And Comprehensive Income Line Items [Line Items]

Issuance of common stock, shares

2,400,000

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Noncontrolling Interest Balances (Detail) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				$ 530,586						$ 530,586
Increase from business combinations										205,100	$ 35,259
Buyout of noncontrolling interests										(86,276)
Distribution to noncontrolling interests									$ (866)	(7,882)	(2,100)
Net loss	$ (6,327)	$ (5,927)	$ (8,660)	(2,160)	$ 4,406	$ (2,073)	$ (4,032)	$ (7,010)		(23,074)	(8,709)	$ (6,887)
Ending balance	944,262				530,586					944,262	530,586
Noncontrolling interest	944,262			530,586	530,586					530,586	530,586		$ 944,262	$ 530,586
Gulf Wind [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				97,061						97,061
Ending balance	0				97,061					0	97,061
Noncontrolling interest	0			97,061	97,061					97,061	97,061		$ 0	$ 97,061
Noncontrolling Ownership Percentage													0.00%	60.00%
El Arrayan [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				35,624						35,624
Ending balance	34,224				35,624					34,224	35,624
Noncontrolling interest	34,224			35,624	35,624					35,624	35,624		$ 34,224	$ 35,624
Noncontrolling Ownership Percentage													30.00%	30.00%
Logan's Gap [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				0						0
Ending balance	190,397				0					190,397	0
Noncontrolling interest	190,397			0	0					0	0		$ 190,397	$ 0
Noncontrolling Ownership Percentage													18.00%
Panhandle 1 [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				205,333						205,333
Ending balance	195,791				205,333					195,791	205,333
Noncontrolling interest	195,791			205,333	205,333					205,333	205,333		$ 195,791	$ 205,333
Noncontrolling Ownership Percentage													21.00%	21.00%
Panhandle 2 [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				192,568						192,568
Ending balance	184,773				192,568					184,773	192,568
Noncontrolling interest	184,773			192,568	192,568					192,568	192,568		$ 184,773	$ 192,568
Noncontrolling Ownership Percentage													19.00%	19.00%
Post Rock [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				0						0
Ending balance	196,346				0					196,346	0
Noncontrolling interest	196,346			0	0					0	0		$ 196,346	$ 0
Noncontrolling Ownership Percentage													40.00%
Amazon Wind Farm Fowler Ridge [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				0						0
Ending balance	142,731				0					142,731	0
Noncontrolling interest	142,731			0	0					0	0		$ 142,731	0
Noncontrolling Ownership Percentage													35.00%
Capital [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				529,539				90,217		529,539	90,217
Contribution from noncontrolling interests										334,231	406,163
Increase from business combinations										205,100	35,259
Buyout of noncontrolling interests										(88,747)
Distribution to noncontrolling interests										(7,882)	(2,100)
Net loss										0	0
Other comprehensive income, net of tax										0	0
Ending balance	972,241				529,539				90,217	972,241	529,539	90,217
Noncontrolling interest	972,241			529,539	529,539			90,217	90,217	529,539	90,217	90,217	$ 972,241	529,539
Accumulated Income (Loss) [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				9,892				18,601		9,892	18,601
Contribution from noncontrolling interests										0	0
Increase from business combinations										0	0
Buyout of noncontrolling interests										(14,244)
Distribution to noncontrolling interests										0	0
Net loss										(23,074)	(8,709)
Other comprehensive income, net of tax										0	0
Ending balance	(27,426)				9,892				18,601	(27,426)	9,892	18,601
Noncontrolling interest	(27,426)			9,892	9,892			18,601	18,601	9,892	18,601	18,601	(27,426)	9,892
Accumulated Other Comprehensive Loss [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				(8,845)				(9,024)		(8,845)	(9,024)
Contribution from noncontrolling interests										0	0
Increase from business combinations										0	0
Buyout of noncontrolling interests										7,944
Distribution to noncontrolling interests										0	0
Net loss										0	0
Other comprehensive income, net of tax										348	179
Ending balance	(553)				(8,845)				(9,024)	(553)	(8,845)	(9,024)
Noncontrolling interest	(553)			(8,845)	(8,845)			(9,024)	(9,024)	(8,845)	(9,024)	(9,024)	(553)	(8,845)
Noncontrolling Interest [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance				530,586				99,794		530,586	99,794
Contribution from noncontrolling interests										334,231	406,163
Increase from business combinations										205,100	35,259
Buyout of noncontrolling interests										(95,047)
Distribution to noncontrolling interests									(866)	(7,882)	(2,100)
Net loss										(23,074)	(8,709)
Other comprehensive income, net of tax										348	179
Ending balance	944,262				530,586				99,794	944,262	530,586	99,794
Noncontrolling interest	$ 944,262			$ 530,586	$ 530,586			$ 99,794	$ 99,794	$ 530,586	$ 99,794	$ 99,794	$ 944,262	$ 530,586

Equity Incentive Award Plan - A

Equity Incentive Award Plan - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Apr. 10, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 4,462	$ 4,105	$ 511
2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be issued under plan					3,000,000
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		2,083,734
2013 Plan [Member] | Restricted Stock [Member] | Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		186,136
2013 Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)				$ 4.11
Shares issued upon exercise of options		0	14,861	0
Cash received from exercise of stock options			$ 300
Aggregate intrinsic value of stock options exercised			100
Unrecorded stock-based compensation expense		$ 500
Unrecorded stock-based compensation expense period of amortization (in years)		9 months
2013 Plan [Member] | RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		100,868
Unrecorded stock-based compensation expense		$ 3,300
Unrecorded stock-based compensation expense period of amortization (in years)		1 year 5 months 19 days
Fair value of restricted stock awards vested		$ 1,700	$ 2,200	$ 200
Weighted average grant date fair value of grants in period (in dollars per share)		$ 29.58	$ 27.63	$ 22.71
Vested (shares)		65,189
Vested (in dollars per share)		$ 26.23
Restricted stock awards unvested		122,868	118,015
2013 Plan [Member] | TSR-RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)	85,268	85,268
Unrecorded stock-based compensation expense		$ 1,700
Unrecorded stock-based compensation expense period of amortization (in years)		2 years 2 months 12 days
Weighted average grant date fair value of grants in period (in dollars per share)		$ 39.16
Target for grants in period (shares)		56,844
Vesting period (in years)	3 years
Vested (shares)		0
Restricted stock awards unvested		85,268	0
2013 Plan [Member] | TSR-RSAs [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	0.00%
2013 Plan [Member] | TSR-RSAs [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	150.00%
2013 Plan [Member] | Performance RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense			$ 600
Vested (shares)			27,717
Vested (in dollars per share)			$ 27.03
Restricted stock awards unvested		0
2013 Plan [Member] | RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		22,772
Fair value of restricted stock awards vested		$ 600
Weighted average grant date fair value of grants in period (in dollars per share)		$ 25.94
Vested (shares)		22,772
Vested (in dollars per share)		$ 25.94
Restricted stock awards unvested		0	0
2013 Plan [Member] | RSUs [Member] | Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		22,772

Equity Incentive Award Plan - W

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

Equity Incentive Award Plan - S

Equity Incentive Award Plan - Summary of Stock Option Activity (Detail) - 2013 Plan [Member] - Stock options [Member] - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Shares
Outstanding, Beginning balance (shares)	429,962
Exercised (shares)	0	(14,861)	0
Forfeited and expired (shares)	0
Outstanding, Ending balance (shares)	429,962	429,962
Exercisable (shares)	318,670
Vested and expected to vest (shares)	429,962
Weighted-Average Exercise Price
Beginning balance (in dollars per share)	$ 22
Exercised (in dollars per share)	22
Forfeited or expired (in dollars per share)	22
Ending balance (in dollars per share)	22	$ 22
Exercisable (in dollars per share)	22
Vested and expected to vest (in dollars per share)	$ 22
Weighted Average Remaining Contractual Life (in years)
Weighted Average Remaining Contractual Life, Outstanding	7 years 9 months 18 days
Weighted Average Remaining Contractual Life, Exercisable	7 years 9 months 18 days
Weighted Average Remaining Contractual Life, Vested and expected to vest	7 years 9 months 18 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$ 0
Aggregate Intrinsic Value, Exercisable	0
Aggregate Intrinsic Value, Vested and expected to vest	$ 0

Equity Incentive Award Plan -97

Equity Incentive Award Plan - Summary of Restricted Stock Awards Activity (Detail) - 2013 Plan [Member] - $ / shares	Apr. 10, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
RSAs [Member]
Shares
Nonvested, Beginning balance		118,015
Granted (shares)		100,868
Vested (shares)		(65,189)
Forfeited (shares)		0
Repurchased for employee tax withholding (shares)		(30,826)
Nonvested, Ending balance		122,868	118,015
Weighted-Average Grant-Date Fair Value
Beginning balance (in dollars per share)		$ 25.29
Granted (in dollars per share)		29.58	$ 27.63	$ 22.71
Vested (in dollars per share)		26.23
Repurchased for employee tax withholding (in dollars per share)		27.67
Ending balance (in dollars per share)		$ 27.71	$ 25.29
TSR-RSAs [Member]
Shares
Nonvested, Beginning balance		0
Granted (shares)	85,268	85,268
Vested (shares)		0
Forfeited (shares)		0
Repurchased for employee tax withholding (shares)		0
Nonvested, Ending balance		85,268	0
Weighted-Average Grant-Date Fair Value
Granted (in dollars per share)		$ 39.16
Ending balance (in dollars per share)		$ 39.16
RSUs [Member]
Shares
Nonvested, Beginning balance		0
Granted (shares)		22,772
Vested (shares)		(22,772)
Forfeited (shares)		0
Repurchased for employee tax withholding (shares)		0
Nonvested, Ending balance		0	0
Weighted-Average Grant-Date Fair Value
Granted (in dollars per share)		$ 25.94
Vested (in dollars per share)		$ 25.94

Loss Per Share (Detail)

Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									9 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share Reconciliation [Abstract]
Potentially dilutive securities excluded from earnings per share calculation (shares)											3,500,000	15,600,000	15,600,000
Numerator for basic and diluted loss per share:
Net loss attributable to Pattern Energy	$ 2,454	$ (29,405)	$ 14,317	$ (19,899)	$ (20,392)	$ (7,208)	$ 11,199	$ (14,889)	$ (13,336)	$ 30,295	$ (32,533)	$ (31,290)	$ 16,959
Less: dividends declared on Class A common shares									(11,103)		(102,893)	(56,976)
Less: earnings allocated to participating securities									0		(32)	0	0
Undistributed loss attributable to common stockholders									(24,439)		(135,426)	(110,167)
Class A Common Stock [Member]
Numerator for basic and diluted loss per share:
Less: dividends declared on Class A common shares									$ (11,103)		(102,861)	(56,976)	(11,103)
Undistributed loss attributable to common stockholders											$ (135,426)	$ (110,167)	$ (24,439)
Weighted average number of shares:
Weighted average number of shares - Basic and diluted (in shares)									35,448,056		70,535,568	42,361,959	35,448,056
Calculation of basic and diluted earnings (loss) per share:
Dividends (in dollars per share)									$ 0.31		$ 1.46	$ 1.34
Undistributed loss (in dollars per share)									(0.48)		(1.92)	(1.90)
Basic loss per share (in dollars per share)					$ (0.36)	$ (0.15)	$ 0.17	$ (0.20)	(0.17)		(0.46)	(0.56)
Diluted loss per share (in dollars per share)					(0.36)	(0.15)	0.16	(0.29)	$ (0.17)		(0.46)	(0.56)
Basic and diluted loss per share (in dollars per share)	$ 0.03	$ (0.40)	$ 0.21	$ (0.30)
Dividends declared per Class A common share (in dollars per share)	$ 0.3720	$ 0.3630	$ 0.3520	$ 0.342	0.34	0.33	0.32	0.31			$ 1.43	$ 1.30	$ 0.31
Class B Common Stock [Member]
Numerator for basic and diluted loss per share:
Less: deemed dividends on Class B common shares									$ 0		$ 0	$ (21,901)	$ 0
Weighted average number of shares:
Weighted average number of shares - Basic and diluted (in shares)									15,555,000		0	15,555,000	15,555,000
Calculation of basic and diluted earnings (loss) per share:
Undistributed loss (in dollars per share)									$ (0.48)		$ 0	$ (1.90)
Deemed dividends (in dollars per share)					0.46	0.46	0.48	0	0		0	1.41	$ 0
Basic and diluted loss per share (in dollars per share)					(0.23)	(0.02)	0.28	(0.51)	(0.48)		0	(0.49)	(0.48)
Deemed dividends per Class B common share (in dollars per share)					$ 0.46	$ 0.46	$ 0.48	$ 0	$ 0		$ 0	$ 1.41	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Future Commitments (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Purchase, construction and other commitments
2016 - Purchase, construction and other commitments	$ 20,661
2017 - Purchase, construction and other commitments	1,419
2018 - Purchase, construction and other commitments	563
2019 - Purchase, construction and other commitments	554
2020 - Purchase, construction and other commitments	591
Thereafter - Purchase, construction and other commitments	5,605
Total - Purchase, construction and other commitments	29,393
Operating leases
2016 - Operating leases	11,103
2017 - Operating leases	12,069
2018 - Operating leases	14,156
2019 - Operating leases	14,637
2020 - Operating leases	14,811
Thereafter - Operating leases	285,977
Total - Operating leases	352,753
Service and maintenance agreements
2016 - Service and maintenance agreements	56,802
2017 - Service and maintenance agreements	51,668
2018 - Service and maintenance agreements	40,936
2019 - Service and maintenance agreements	34,149
2020 - Service and maintenance agreements	31,556
Thereafter - Service and maintenance agreements	146,981
Total - Service and maintenance agreements	362,092
Total commitments
2016 - Total commitments	88,566
2017 - Total commitments	65,156
2018 - Total commitments	55,655
2019 - Total commitments	49,340
2020 - Total commitments	46,958
Thereafter - Total commitments	438,563
Contractual Obligation	$ 744,238

Commitments and Contingencie100

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Commitments [Line Items]
Revenue sharing commitment	$ 362,092
Rent expense	$ 12,000	$ 8,800	$ 6,100
Annual inflation price adjustment percentage	2.00%
Power Sale Agreements [Member]
Other Commitments [Line Items]
Letters-of-credit outstanding	$ 229,200
Project Finance Agreements [Member]
Other Commitments [Line Items]
Letters-of-credit outstanding	108,100
Turbine manufacturers [Member]
Other Commitments [Line Items]
Turbine availability bonus payable	800
Service Providers [Member]
Other Commitments [Line Items]
Turbine availability bonus payable	$ 1,400
Acquisition commitment [Member]
Other Commitments [Line Items]
Percent of gross revenue entitled to third party	1.00%
Revenue sharing commitment	$ 2,500
Agreement term (in years)	13 years
Service and Maintenance Agreements [Member]
Other Commitments [Line Items]
Agreement term (in years)	19 years

Related Party Transactions - Al

Related Party Transactions - Allocated Costs Included in Combined Statement of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Related party general and administrative	$ 7,589	$ 5,787	$ 8,169
Related party income	(2,665)	(2,612)	(665)
Bilateral Management Service Cost Reimbursement [Member]
Related Party Transaction [Line Items]
Project expense	0	0	1,995
Related party general and administrative	7,589	5,787	8,169
Other (expense) income, net	0	0	(551)
Total	$ 4,924	$ 3,175	$ 8,948

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) CAD in Millions

Dec. 18, 2015USD ($)

Jul. 28, 2015USD ($)

Jun. 17, 2015USD ($)MW

Apr. 29, 2015USD ($)MW

Dec. 19, 2014USD ($)MW

Nov. 10, 2014USD ($)MW

Jun. 30, 2014USD ($)MW

Jun. 25, 2014USD ($)MW

Nov. 30, 2015USD ($)

Sep. 30, 2015USD ($)

Sep. 30, 2015CAD

Dec. 31, 2015USD ($)

Dec. 31, 2014USD ($)

Dec. 31, 2013USD ($)

Jun. 30, 2015

Jun. 24, 2014

Dec. 20, 2013CAD

Related Party Transaction [Line Items]

Percentage of service fees of direct cost incurred by related party

5.00%

Amounts receivable from related party

$ 600,000

$ 700,000

Contingent liabilities paid

515,000

0

$ 0

Management fees

$ 3,640,000

3,317,000

911,000

Employer contribution, percentage

5.00%

Employer contribution, amount

$ 500,000

300,000

100,000

Management Fees [Member]

Related Party Transaction [Line Items]

Management fees

3,600,000

3,300,000

900,000

Pattern Development [Member] | Bilateral Management Service Cost Reimbursement [Member]

Related Party Transaction [Line Items]

Amounts payable to related party

1,600,000

800,000

Amounts receivable from related party

100,000

100,000

Gulf Wind [Member]

Related Party Transaction [Line Items]

Business acquisition price

$ 72,800,000

Gulf Wind [Member] | Pattern Development [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

27.00%

Business acquisition price

$ 13,000,000

Fowler RidgeIv Wind Farm Llc [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Contingent payment possible

$ 29,100,000

Contingent liabilities paid

$ 27,200,000

Business acquisition price

37,500,000

Contingent obligations incurred

$ 14,800,000

Power generation capacity | MW

150

Transaction related expenses

600,000

Fowler RidgeIv Wind Farm Llc [Member] | Pattern Development [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Contingent liabilities paid

$ 27,200,000

Business acquisition price

$ 37,500,000

Power generation capacity | MW

150

Transaction related expenses

$ 600,000

Logan's Gap [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Contingent liabilities paid

6,300,000

Business acquisition price

$ 15,100,000

Transaction related expenses

$ 100,000

300,000

Logan's Gap [Member] | Pattern Development [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 15,100,000

Power generation capacity | MW

164

Panhandle 2 [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 123,800,000

Debt assumed

$ 195,351,000

Capacity acquired | MW

147

Power generation capacity | MW

182

Transaction related expenses

200,000

$ 600,000

Equity interest in company percentage

81.00%

Panhandle 2 [Member] | Class B Members [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Panhandle 1 [Member]

Related Party Transaction [Line Items]

Power generation capacity | MW

218

Transaction related expenses

500,000

Panhandle 1 [Member] | Class B Members [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Panhandle 1 [Member] | Pattern Development [Member]

Related Party Transaction [Line Items]

Business acquisition price

$ 124,400,000

Capacity acquired | MW

172

Power generation capacity | MW

218

Equity interest in company percentage

79.00%

Panhandle 1 [Member] | Pattern Development [Member] | Class B Members [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

AEI El Arrayan [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

100.00%

Business acquisition price

$ 45,300,000

El Arrayan [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

38.50%

Business acquisition price

$ 45,300,000

Power generation capacity | MW

115

Transaction related expenses

$ 400,000

Equity interest in company percentage

70.00%

Indirect interest (percentage)

31.50%

31.50%

El Arrayan [Member] | Majority control [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

70.00%

Grand Renewable Wind L P [Member] | Pattern Development [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

45.00%

Contingent payment possible | CAD

CAD 5

Contingent liabilities paid

$ 1,800,000

CAD 2.4

K2 [Member]

Related Party Transaction [Line Items]

Ownership interest acquired (percent)

33.33%

Business acquisition price

$ 128,000,000

$ 132,400,000

Contingent obligations incurred

4,000,000

K2 [Member] | Pattern Development [Member]

Related Party Transaction [Line Items]

Business acquisition price

128,400,000

132,400,000

Debt assumed

$ 221,800,000

Contingent obligations incurred

$ 4,000,000

Capacity acquired | MW

90

Power generation capacity | MW

270

Selected Quarterly Financial103

Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									9 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule Of Quarterly Financial Information [Line Items]
Revenue	$ 90,597	$ 89,697	$ 84,671	$ 64,866	$ 79,418	$ 71,519	$ 65,007	$ 49,549			$ 329,831	$ 265,493	$ 201,573
Gross profit	16,674	22,250	22,348	10,564	26,311	17,669	27,023	12,298			71,836	83,301	60,716
Net (loss) income	(3,873)	(35,332)	5,657	(22,059)	(15,986)	(9,281)	7,167	(21,899)	$ (19,533)	$ 29,605	(55,607)	(39,999)	10,072
Net income (loss) attributable to noncontrolling interest	(6,327)	(5,927)	(8,660)	(2,160)	4,406	(2,073)	(4,032)	(7,010)			(23,074)	(8,709)	(6,887)
Net (loss) income attributable to Pattern Energy	$ 2,454	$ (29,405)	$ 14,317	$ (19,899)	$ (20,392)	$ (7,208)	$ 11,199	$ (14,889)	$ (13,336)	$ 30,295	$ (32,533)	$ (31,290)	$ 16,959
Class A Common Stock [Member]
Schedule Of Quarterly Financial Information [Line Items]
Basic and diluted (loss) earnings per share (in dollars per share)	$ 0.03	$ (0.40)	$ 0.21	$ (0.30)
Basic (loss) earnings per share (in dollars per share)					$ (0.36)	$ (0.15)	$ 0.17	$ (0.20)	$ (0.17)		$ (0.46)	$ (0.56)
Diluted (loss) earnings per share (in dollars per share)					(0.36)	(0.15)	0.16	(0.29)	(0.17)		(0.46)	(0.56)
Dividends declared per Class A common share (in dollars per share)	$ 0.3720	$ 0.3630	$ 0.3520	$ 0.342	0.34	0.33	0.32	0.31			1.43	1.30	$ 0.31
Class B Common Stock [Member]
Schedule Of Quarterly Financial Information [Line Items]
Basic and diluted (loss) earnings per share (in dollars per share)					(0.23)	(0.02)	0.28	(0.51)	(0.48)		0	(0.49)	(0.48)
Deemed dividends (in dollars per share)					$ 0.46	$ 0.46	$ 0.48	$ 0	$ 0		$ 0	$ 1.41	$ 0

Subsequent Events (Detail)

Subsequent Events (Detail) - USD ($) $ / shares in Units, $ in Thousands	Feb. 24, 2016	Feb. 03, 2016	Jan. 01, 2016	Dec. 31, 2015
Subsequent Event [Line Items]
Total future lease payments incurred				$ 352,753
Class A Common Stock [Member]
Subsequent Event [Line Items]
Dividends payable (in dollars per share)				$ 0.3720
Subsequent Event [Member] | Class A Common Stock [Member]
Subsequent Event [Line Items]
Dividends payable (in dollars per share)	$ 0.3810
Dividends payable annualized (in dollars per share)	$ 1.524
Change in dividend payable percentage	2.40%
Subsequent Event [Member] | Houston, Texas Office Facilities [Member]
Subsequent Event [Line Items]
Total future lease payments incurred		$ 14,100
Subsequent Event [Member] | San Francisco, California Office Facilities [Member]
Subsequent Event [Line Items]
Total future lease payments incurred			$ 38,700

Schedule I-Condensed Parent-105

Schedule I-Condensed Parent-Company Financial Statements - Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 94,808	$ 101,656	$ 103,569		$ 17,574
Related party receivable	734	671
Derivative assets, current	24,338	18,506
Current net deferred tax assets	0	318
Prepaid expenses	14,498	15,275
Other current assets	6,891	12,679
Total current assets	203,329	197,088
Restricted cash	36,875	39,745
Unconsolidated investments	116,473	29,079
Derivative assets	44,014	49,369
Net deferred tax assets	6,804	5,474
Other assets	25,183	11,421
Total assets	3,829,592	2,795,287
Current liabilities:
Accounts payable and other accrued liabilities	42,776	24,793
Related party payable	1,646	5,757
Accrued interest	9,035	3,634
Dividend payable	28,022	15,734
Current deferred tax liabilities	0	149
Total current liabilities	520,687	250,199
Convertible senior notes, net of financing costs of $5,014 and $0 as of December 31, 2015 and 2014, respectively	197,362	0
Net deferred tax liabilities	22,183	20,418
Total liabilities	2,053,830	1,630,553
Equity:
Common stock	747	621
Additional paid-in capital	982,814	723,938
Accumulated loss	(77,159)	(44,626)
Accumulated other comprehensive loss	(73,325)	(45,068)
Treasury stock, at cost; 65,301 and 25,465 shares of Class A common stock as of December 31, 2015 and 2014, respectively	(1,577)	(717)
Total equity	1,775,762	1,164,734	568,004	$ 569,828	589,412
Total liabilities and equity	3,829,592	2,795,287
Pattern Energy Group Inc [Member]
Current assets:
Cash and cash equivalents	26,938	34,772	$ 75,776		$ 1
Related party receivable	3,050	1,982
Derivative assets, current	3,482	0
Current net deferred tax assets	0	307
Prepaid expenses	487	514
Other current assets	381	3,970
Total current assets	34,338	41,545
Restricted cash	250	0
Investments in subsidiaries	918,270	586,641
Unconsolidated investments	116,473	29,079
Derivative assets	628	0
Net deferred tax assets	0	147
Other assets	0	85
Total assets	1,069,959	657,497
Current liabilities:
Accounts payable and other accrued liabilities	7,590	6,404
Related party payable	1,643	757
Accrued interest	3,842	0
Dividend payable	28,022	15,734
Current deferred tax liabilities	0	147
Total current liabilities	41,097	23,042
Convertible senior notes, net of financing costs of $5,014 and $0 as of December 31, 2015 and 2014, respectively	197,362	0
Net deferred tax liabilities	0	307
Total liabilities	238,459	23,349
Equity:
Additional paid-in capital	955,254	696,378
Capital	0	0
Accumulated loss	(49,599)	(17,066)
Accumulated other comprehensive loss	(73,325)	(45,068)
Total equity	831,500	634,148
Total liabilities and equity	1,069,959	657,497
Pattern Energy Group Inc [Member] | Class A Common Stock [Member]
Equity:
Common stock	747	621
Treasury stock, at cost; 65,301 and 25,465 shares of Class A common stock as of December 31, 2015 and 2014, respectively	$ (1,577)	$ (717)

Schedule I-Condensed Parent-106

Schedule I-Condensed Parent-Company Financial Statements - Balance Sheets (Parenthetical) (Detail) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Condensed Balance Sheet Statements, Captions [Line Items]
Financing costs - Convertible senior notes	$ (5,014)	$ 0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares outstanding	74,644,141	62,062,841
Treasury stock, shares	65,301	25,465
Pattern Energy Group Inc [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Financing costs - Convertible senior notes	$ (5,014)	$ 0
Treasury stock, shares	65,301	25,465
Pattern Energy Group Inc [Member] | Class A Common Stock [Member]
Condensed Balance Sheet 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 outstanding	74,644,141	62,062,841

Schedule I-Condensed Parent-107

Schedule I-Condensed Parent-Company Financial Statements - Statements of Operations and Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended									9 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Income Statements, Captions [Line Items]
Revenue	$ 90,597	$ 89,697	$ 84,671	$ 64,866	$ 79,418	$ 71,519	$ 65,007	$ 49,549			$ 329,831	$ 265,493	$ 201,573
Expenses											37,396	28,320	12,988
Operating income											34,440	54,981	47,728
Other (expense) income:
Interest expense											(77,907)	(67,694)	(63,614)
Equity in earnings (losses) in unconsolidated investments											16,119	(25,295)	7,846
(Loss) gain on undesignated derivatives, net											(5,490)	(15,743)	13,502
Total other expense											(85,104)	(91,844)	(33,110)
Net (loss) income before income tax											(50,664)	(36,863)	14,618
Tax provision											(4,943)	(3,136)	(4,546)
Net (loss) income	$ (3,873)	$ (35,332)	$ 5,657	$ (22,059)	$ (15,986)	$ (9,281)	$ 7,167	$ (21,899)	$ (19,533)	$ 29,605	(55,607)	(39,999)	10,072
Other comprehensive income (loss), net of tax
Proportionate share of affiliates' other comprehensive (loss) income activity, net of tax benefit (provision) of $1,524, $1,855 and ($615), respectively											(4,228)	(5,991)	2,473
Total other comprehensive (loss) income, net of tax									$ 6,847	$ 24,192	(19,965)	(36,536)	31,039
Comprehensive (loss) income attributable to Pattern Energy											(52,846)	(68,005)	42,910
Pattern Energy Group Inc [Member]
Condensed Income Statements, Captions [Line Items]
Revenue											0	0	0
Expenses											29,483	23,089	3,630
Operating income											(29,483)	(23,089)	(3,630)
Other (expense) income:
Interest expense											(6,107)	0	0
Equity in (losses) earnings from subsidiaries											(19,058)	18,064	12,641
Equity in earnings (losses) in unconsolidated investments											16,119	(25,295)	7,846
(Loss) gain on undesignated derivatives, net											5,107	0	0
Related party income											2,665	2,612	665
Other expenses, net											(1,558)	(3,566)	(563)
Total other expense											(2,832)	(8,185)	20,589
Net (loss) income before income tax											(32,315)	(31,274)	16,959
Tax provision											(218)	(16)	0
Net (loss) income											(32,533)	(31,290)	16,959
Other comprehensive income (loss), net of tax
Proportionate share of subsidiaries' other comprehensive (loss) income, net of tax benefit of $1,206, $514 and $0, respectively											(16,085)	(30,724)	23,478
Proportionate share of affiliates' other comprehensive (loss) income activity, net of tax benefit (provision) of $1,524, $1,855 and ($615), respectively											(4,228)	(5,991)	2,473
Total other comprehensive (loss) income, net of tax											(20,313)	(36,715)	25,951
Comprehensive (loss) income attributable to Pattern Energy											$ (52,846)	$ (68,005)	$ 42,910

Schedule I-Condensed Parent-108

Schedule I-Condensed Parent-Company Financial Statements - Statements of Operations and Comprehensive Income (Loss) (Parenthetical) (Detail) - Pattern Energy Group Inc [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Income Statements, Captions [Line Items]
Proportionate share of subsidiaries’ other comprehensive (loss) income activity, tax	$ 1,206	$ 514	$ 0
Proportionate share of equity investee's other comprehensive (loss) income activity, net of tax benefit (provision)	$ 1,524	$ 1,855	$ (615)

Schedule I-Condensed Parent-109

Schedule I-Condensed Parent-Company Financial Statements - Statements of Cash Flows (Detail) - USD ($) $ in Thousands	3 Months Ended									9 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Oct. 01, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities
Net (loss) income	$ (3,873)	$ (35,332)	$ 5,657	$ (22,059)	$ (15,986)	$ (9,281)	$ 7,167	$ (21,899)	$ (19,533)	$ 29,605	$ (55,607)	$ (39,999)	$ 10,072
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Amortization of financing costs											7,435	6,309	6,816
Amortization of debt discount/premium, net											1,660	0	0
Loss (gain) on derivatives, net											2,219	15,546	(4,329)
Stock-based compensation											4,462	4,105	511
Net loss on transactions											0	(16,526)	(5,995)
Equity in (earnings) losses from affiliates											(16,119)	25,295	(7,846)
Changes in operating assets and liabilities:
Prepaid expenses											1,272	(4,100)	(7,021)
Other current assets											(2,929)	17,016	4,323
Accounts payable and other accrued liabilities											4,716	3,667	3,036
Related party receivable/payable											711	(942)	190
Accrued interest payable											4,489	1,377	(33)
Net cash provided by operating activities											117,849	110,448	78,152
Cash paid for acquisitions, net of cash acquired											(433,792)	(306,584)	(30,070)
Investing activities
Increase in restricted cash											(57,332)	(40,790)	(80,569)
Net cash (used in) provided by investing activities											(765,203)	(379,380)	72,391
Financing activities
Proceeds from public offering, net of issuance costs											317,432	286,757	317,926
Proceeds from issuance of convertible senior notes, net of issuance costs											218,929	0	0
Proceeds from exercise of stock options											0	327	0
Refund of deposit for letters of credit											3,425	(3,422)	0
Repurchase of shares for employee tax withholding											(860)	(693)	(24)
Capital contributions - Pattern Development											0	0	32,679
Capital distributions - Pattern Development											0	0	(98,886)
Dividends paid											(90,582)	(52,344)	0
Payment for deferred equity issuance costs											0	(550)	0
Net cash provided by financing activities											645,299	268,989	(63,401)
Net change in cash and cash equivalents											(6,848)	(1,913)	85,995
Cash and cash equivalents at beginning of period				101,656				103,569		17,574	101,656	103,569	17,574
Cash and cash equivalents at end of period	94,808				101,656				103,569		94,808	101,656	103,569
Schedule of non-cash activities
Cash payments for income taxes											342	131	0
Equity issuance costs paid in prior period related to current period offerings											(433)	0	(884)
Non-cash increase in additional paid-in capital from buyout of noncontrolling interests											16,715	0	0
Pattern Energy Group Inc [Member]
Operating activities
Net (loss) income											(32,533)	(31,290)	16,959
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Amortization of financing costs											472	0	0
Amortization of debt discount/premium, net											1,794	0	0
Loss (gain) on derivatives, net											(4,110)	0	0
Stock-based compensation											4,462	4,105	511
Net loss on transactions											0	1,473	0
Equity in losses (earnings) from subsidiaries											19,058	(18,064)	(12,641)
Equity in (earnings) losses from affiliates											(16,119)	25,295	(7,846)
Changes in operating assets and liabilities:
Prepaid expenses											35	(93)	(428)
Other current assets											43	(3,452)	(18)
Accounts payable and other accrued liabilities											473	1,999	93
Related party receivable/payable											(183)	(639)	(1,007)
Accrued interest payable											3,842	0	0
Net cash provided by operating activities											(22,766)	(20,666)	(4,377)
Cash paid for acquisitions, net of cash acquired											(65,042)	0	0
Investing activities
Distribution from subsidiaries											(613,089)	108,581	233,226
Contribution to subsidiaries											244,969	(362,533)	(172,130)
Increase in restricted cash											(250)	0	0
Net cash (used in) provided by investing activities											(433,412)	(253,952)	61,096
Financing activities
Proceeds from public offering, net of issuance costs											317,432	286,757	317,926
Proceeds from issuance of convertible senior notes, net of issuance costs											218,929	0	0
Proceeds from exercise of stock options											0	327	0
Refund of deposit for letters of credit											3,425	0	0
Repurchase of shares for employee tax withholding											(860)	(693)	(24)
Capital contributions - Pattern Development											0	0	32,678
Capital distributions - Pattern Development											0	0	(98,884)
Capital distributions - Contribution Transactions											0	0	(232,640)
Dividends paid											(90,582)	(52,344)	0
Payment for deferred equity issuance costs											0	(433)	0
Net cash provided by financing activities											448,344	233,614	19,056
Net change in cash and cash equivalents											(7,834)	(41,004)	75,775
Cash and cash equivalents at beginning of period				$ 34,772				$ 75,776		$ 1	34,772	75,776	1
Cash and cash equivalents at end of period	$ 26,938				$ 34,772				$ 75,776		26,938	34,772	75,776
Schedule of non-cash activities
Cash payments for income taxes											218	16	0
Equity issuance costs paid in prior period related to current period offerings											(433)	0	0
Non-cash increase in additional paid-in capital from buyout of noncontrolling interests											$ 16,715	$ 0	$ 0