Niska Gas Storage Partners (NKA) Inactive 10-K12 Jun 152015 FY Annual reportFinancial data

Company Profile

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
Document and Entity Information (USD $)	Mar. 31, 2015	Jun. 12, 2015	Sep. 30, 2014
Document and Entity Information
Entity Registrant Name	Niska Gas Storage Partners LLC
Entity Central Index Key	1483830
Document Type	10-K
Document Period End Date	31-Mar-15
Amendment Flag	FALSE
Current Fiscal Year End Date	-28
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$218,401,036
Entity Common Stock, Shares Outstanding		37,988,724
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY

Consolidated_Statements_of_Ear

Consolidated Statements of Earnings (Loss) and Comprehensive Income (Loss) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
REVENUES:
Fee-based revenue (Note 15)	$92,340	$135,356	$163,325
Optimization, net (Note 15)	5,979	72,040	-22,630
Total revenues	98,319	207,396	140,695
EXPENSES (INCOME)
Operating	39,230	40,834	32,535
General and administrative	26,833	39,937	38,562
Depreciation and amortization (Notes 4, 5 and 16)	117,323	41,286	50,409
Interest (Notes 6 and 17)	51,336	66,315	67,010
Loss on extinguishment of debt (Notes 6 and 7)		36,697	599
Impairment of goodwill (Note 5)	245,604
(Gain) loss on disposal of assets (Note 4)	-64		14,927
Foreign exchange losses (gains)	380	1,182	-694
Other (income) expense	-11	358	-110
EARNINGS (LOSS) BEFORE INCOME TAXES	-382,312	-19,213	-62,543
Income tax expense (benefit) (Note 11)
Current	2,595	82	-1,414
Deferred	-34,251	-10,338	-17,528
Income tax expense (benefit)	-31,656	-10,256	-18,942
NET EARNINGS (LOSS) AND COMPREHENSIVE INCOME (LOSS)	-350,656	-8,957	-43,601
Net earnings (loss) allocated to:
Managing Member	-6,352	-171	-863
Common unitholders	-344,304	-8,786	-21,584
Subordinated unitholder (Note 14)			($21,154)
Earnings (loss) per unit allocated to common unitholders
basic (in dollars per unit)	($9.34)	($0.25)	($0.63)
diluted (in dollars per unit)	($9.34)	($0.25)	($0.63)
Earnings (loss) per unit allocated to subordinated unitholders (Note 14)
basic (in dollars per unit) (Note 14)			-0.63
diluted (in dollars per unit) (Note 14)			-0.63

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Current Assets
Cash and cash equivalents	$11,699	$7,704
Margin deposits	13,285	32,626
Trade receivables	2,598	5,760
Accrued receivables	44,140	150,628
Natural gas inventory	136,295	75,140
Prepaid expenses and other current assets	3,788	4,330
Short-term risk management assets (Notes 12 and 13)	41,600	20,949
Total current assets	253,405	297,137
Long-term Assets
Property, plant and equipment, net of accumulated depreciation (Note 4)	820,467	908,274
Goodwill (Note 5)		245,604
Intangible assets, net of accumulated amortization (Note 5)	41,829	65,462
Deferred financing costs, net of accumulated amortization (Note 6)	11,001	14,640
Other assets	3,329	3,268
Long-term risk management assets (Notes 12 and 13)	30,928	4,806
Total long-term assets	907,554	1,242,054
TOTAL	1,160,959	1,539,191
Current Liabilities
Revolving credit facilities (Note 7)	193,500	119,500
Current portion of obligations under capital lease (Note 8)	1,339	1,299
Trade payables	885	1,023
Current portion of deferred taxes (Note 11)	2,334	5,678
Deferred revenue	6,669	6,036
Accrued liabilities (Note 9)	47,686	111,118
Short-term risk management liabilities (Notes 12 and 13)	25,560	19,105
Total current liabilities	277,973	263,759
Long-term Liabilities
Long-term risk management liabilities (Notes 12 and 13)	20,833	12,209
Asset retirement obligations (Note 10)	2,308	1,975
Other long-term liabilities	1,270	1,809
Deferred income taxes (Note 11)	88,317	119,373
Obligations under capital lease (Note 8)	9,587	10,926
Long-term debt (Note 7)	575,000	575,000
Total long-term liabilities	697,315	721,292
MEMBERS' EQUITY
Common units	-81,805	279,604
Managing Member's interest	267,476	274,536
Total members' equity	185,671	554,140
Commitments and contingencies (Notes 7, 14 and 19)
TOTAL	$1,160,959	$1,539,191

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Operating Activities
Net earnings (loss)	($350,656)	($8,957)	($43,601)
Adjustments to reconcile net earnings (loss) to net cash (used in) provided by operating activities:
Unrealized foreign exchange losses (gains)	372	1,500	-252
Deferred income tax benefit (Note 11)	-34,251	-10,338	-17,528
Unrealized risk management (gains) losses (Notes 12 and 13)	-31,694	8,732	89,851
Depreciation and amortization (Notes 4, 5 and 16)	117,323	41,286	50,409
Amortization of deferred financing costs (Notes 6 and 17)	3,652	3,354	3,411
Loss on extinguishment of debt (Notes 6 and 7)		36,697	599
(Gain) loss on disposal of assets (Note 4)	-64		14,927
Impairment of goodwill (Note 5)	245,604
Non-cash compensation (Note 14)	2,305
Write-downs of inventory (Note 15)	63,800	4,600	22,281
Changes in non-cash working capital (Note 20)	-55,835	15,033	42,033
Net cash (used in) provided by operating activities	-39,444	91,907	162,130
Investing Activities
Property, plant and equipment expenditures	-7,587	-3,159	-30,015
Purchase of customer contracts		-2,007
Proceeds on disposal of assets	14		2,210
Net cash used in investing activities	-7,573	-5,166	-27,805
Financing Activities
Proceeds from debt issuance		575,000
Debt redemption / repurchase		-672,361
Proceeds on revolver drawings	712,700	784,500	348,448
Revolver repayments	-638,700	-730,000	-433,448
Payments of financing costs	-857	-10,855	-3,248
Payments of unit issuance costs	-13	-218
Proceeds from obligations under capital lease			947
Repayments of obligations under capital lease	-1,299	-1,259	-717
Distributions to unitholders (Note 14)	-20,105	-34,051	-48,811
Net cash provided by (used in) financing activities	51,726	-89,244	-136,829
Effect of translation on foreign currency cash and cash equivalents	-714	-403	-228
Net increase (decrease) in cash and cash equivalents	3,995	-2,906	-2,732
Cash and cash equivalents, beginning of the year	7,704	10,610	13,342
Cash and cash equivalents, end of the year	$11,699	$7,704	$10,610

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Members' Equity (USD $)	Common Units	Subordinated Units	Managing Member's Interest	Total
In Thousands, unless otherwise specified	Common Units	Subordinated Units	Managing Member's Interest	Total
Balance at Mar. 31, 2012	$391,585	$287,105	$11,700	$690,390
Increase (Decrease) in Stockholders' Equity
Net earnings (loss)	-21,584	-21,154	-863	-43,601
Distributions to unitholders	-48,359	-74	-979	-49,412
Balance at Mar. 31, 2013	321,642	265,877	9,858	597,377
Increase (Decrease) in Stockholders' Equity
Cancellation of subordinated units		-265,877	265,877
Net earnings (loss)	-8,786		-171	-8,957
Distributions to unitholders	-51,293		-1,028	-52,321
Issuance of common units	18,041			18,041
Balance at Mar. 31, 2014	279,604		274,536	554,140
Increase (Decrease) in Stockholders' Equity
Net earnings (loss)	-344,304		-6,352	-350,656
Distributions to unitholders	-38,985		-751	-39,736
Issuance of common units	19,618			19,618
Non-cash equity contribution from parent	480		10	490
Non-cash compensation expense	1,782		33	1,815
Balance at Mar. 31, 2015	($81,805)		$267,476	$185,671

Description_of_Business

Description of Business	12 Months Ended
Description of Business	Mar. 31, 2015
Description of Business
Description of Business
	1. Description of Business
	Niska Gas Storage Partners LLC ("Niska Partners" or the "Company") is a publicly-traded Delaware limited liability company (NYSE:NKA) which independently owns and/or operates natural gas storage assets in North America. The Company operates the Countess and Suffield gas storage facilities (collectively, the AECO Hub™) in Alberta, Canada, and the Wild Goose and Salt Plains gas storage facilities in California and Oklahoma, respectively. Each of these facilities markets natural gas storage services in addition to optimizing storage capacity with its own proprietary gas purchases.
	At March 31, 2015, Niska Partners had 37,988,724 common units outstanding. Of this amount, 20,488,525 common units were held by Niska Sponsor Holdings Coopertief U. A. ("Holdco"), along with a 1.80% Managing Member's interest in the Company and all of the Incentive Distribution Rights ("IDRs"). Holdco is indirectly owned by Carlyle/Riverstone Energy and Power Fund II and Carlyle/Riverstone Energy and Power Fund III and certain affiliates (together, the "Carlyle/Riverstone Funds"). Including all of the common units owned by the Carlyle/Riverstone Funds, along with the 1.80% Managing Member's interest, the Carlyle/Riverstone Funds had a 54.76% ownership interest in the Company, excluding IDRs. The remaining 17,500,199 common units, representing a 45.24% ownership interest excluding the IDRs, were owned by the public.
	In fiscal 2015, the Company was unfavorably impacted by reductions in natural gas prices, associated margin amounts required by our retail marketing operations, and costs associated with requirements for temporary reservoir pressure support. This prevented the Company from realizing profit and negatively impacted the liquidity available under the $400.0 million revolving credit facilities. Continued reduction in amounts available under the Company's revolving credit facilities may restrict the Company's ability to pursue its revenue strategies, which may have a material adverse effect on the Company's revenues and profitability, and certain customary covenants related to our credit agreement, including a covenant that requires the maintenance of a fixed charge coverage ratio of 1.1 to 1.0 (Note 7). The Company expects that the FCCR will likely fall below 1.1 to 1.0 in the quarter ending June 30, 2015, which will result in the last 15% of the Company's borrowing base becoming unavailable for borrowing. The Company is pursuing strategies, which include reductions in operating and general and administrative costs as well as management of the components of the borrowing base, which should assist it in maintaining adequate liquidity despite this covenant provision.

Significant_Accounting_Policie

Significant Accounting Policies	12 Months Ended
	Mar. 31, 2015
Significant Accounting Policies
Significant Accounting Policies
	2. Significant Accounting Policies
	Basis of presentation
	These consolidated financial statements have been prepared to reflect the consolidated financial position, results of operations and cash flows of Niska Partners and its subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP").
	These financial statements include the accounts of Niska Partners and its wholly-owned subsidiaries, including AECO Gas Storage Partnership, Wild Goose Storage LLC, Niska Gas Storage, LLC, Salt Plains Storage, LLC, Access Gas Services Inc., Access Gas Services (Ontario) Inc., EnerStream Agency Services Inc., and Niska Partners Management ULC. All material intercompany transactions have been eliminated, as well as various management and holding companies.
	Use of estimates
	In preparing these financial statements, Niska Partners is required to make estimates and assumptions that affect both the amount and timing of recording assets, liabilities, revenues and expenses since the determination of these items may be dependent on future events. Management uses the most current information available and exercises careful judgment in making these estimates. Although management believes that these consolidated financial statements have been prepared within the limits of materiality and within the framework of its significant accounting policies summarized below, actual results could differ from these estimates. Changes in estimates are accounted for on a prospective basis.
	Revenue recognition
	The Company's assessment of each of the four revenue recognition criteria as they relate to its revenue producing activities is as follows:
	Persuasive evidence of an arrangement exists. The Company's customary practices are to enter into a written contract, executed by both the customer and the Company.
	Delivery. Delivery is deemed to have occurred at the time the natural gas is delivered and title is transferred, or in the case of fee-based arrangements, when the services are rendered. To the extent the Company retains its inventory, delivery occurs when the inventory is subsequently sold and title is transferred to the third-party purchaser.
	The fee is fixed or determinable. The Company negotiates the fee for its services at the outset of their fee-based arrangements. In these arrangements, the fees are nonrefundable. The fees are generally due on the 25th of the month following the delivery or services rendered. For other arrangements, the amount of revenue is determinable when the sale of the applicable product has been completed upon delivery and transfer of title.
	Collectability is reasonably assured. Collectability is evaluated on a customer-by-customer basis. New and existing customers are subject to a credit review process, which evaluates the customers' financial position (e.g. cash position and credit rating) and their ability to pay. If collectability is not considered reasonably assured at the outset of an arrangement in accordance with the Company's credit review process, revenue is recognized when the fee is collected.
	Fee-based revenue consists of long-term contracts for storage fees that are generated when we lease storage capacity on a monthly basis and short-term fees associated with park and loan activities. Long-term contract revenue consists of monthly storage fees and fuel and commodity charges for injections and withdrawals. Long-term contract revenue is accrued on a monthly basis in accordance with the terms of the customer contracts. Customer charges for injections and withdrawals are recorded in the month of injection or withdrawal. Short-term contract revenue consists of fees for injections and withdrawals, where the customer pays a fixed fee to inject a specified quantity of natural gas on a specified date or dates and withdraw a specified quantity of natural gas on a specified date. The fee stipulated in a short-term contract for each performance obligation (injection and withdrawal) is recognized when the service occurs.
	Energy trading contracts resulting in the delivery of a commodity where Niska Partners is the principal in the transaction are recorded as optimization revenues at the time of physical delivery. Realized and unrealized gains and losses on financial energy trading contracts are included in optimization revenue (see Note 12).
	Optimization revenue, net includes realized gains and losses and the net change in unrealized gains and losses on financial and physical energy trading contracts. Optimization revenue results from the purchase of inventory and its forward sale to future periods through financial and physical trading contracts. These derivative contracts are economic hedges that have been entered into to manage commodity price and currency risk associated with buying and selling natural gas across future time periods (see Note 12). The Company does not designate these instruments as hedges and therefore records the unrealized gains and losses on the changes in their fair value through net earnings. Contracts resulting in the delivery of a commodity where Niska Partners is the principal in the transaction are recorded as optimization revenues at the time of physical delivery.
	Sales taxes collected from customers and remitted to governmental authorities are excluded from revenues in the consolidated statements of earnings (loss) and comprehensive income (loss).
	Cash and cash equivalents
	Niska Partners considers all highly liquid investments purchased with an initial maturity of three months or less to be cash equivalents.
	Margin deposits
	Cash held in margin represents the right to receive or the obligation to pay cash collateral under a master netting arrangement that has not been offset against derivative positions. These derivatives are marked-to-market daily; the profit or loss on the daily position is then paid to, or received from, the account as appropriate under the terms of the Company's contract with its broker.
	Natural gas inventory
	The Company's inventory is natural gas injected into storage which is held for resale. Inventory is valued at the lower of weighted average cost or market. Adjustments to write down the costs of inventory to market are recorded as an offset to optimization revenues while costs to store the gas are recognized as operating expenses in the period the costs are incurred in the consolidated statements of earnings (loss) and comprehensive income (loss).
	Property, plant and equipment
	Property, plant and equipment are recorded at cost when purchased. Depreciation is computed using the declining balance method for each category of asset using the following rates:

	Pipelines and measurement	5%
	Wells	5%
	Facilities (excluding costs of major overhauls)	Between 5% and 22%
	Computer hardware and software	30%
	Office furniture and fixtures	20%
	Other	10%
	Property, plant and equipment under capital leases are depreciated using the declining balance method over the lesser of the useful lives of the assets or the lease term.
	Costs of major overhauls of engines and compressors included within the facilities account are depreciated using the actual number of hours used over the estimated number of hours until the next scheduled major overhaul.
	Certain volumes of hydrocarbons defined as cushion are required for maintaining a minimum field pressure. Cushion is considered a component of the facility and as such is not amortized. Cushion is monitored to ensure that it provides effective pressure support for the facility. In the event that cushion moves to another area of the reservoir where it does not provide effective pressure support, a loss is recorded, within depreciation expense, equal to the estimated volumes that have migrated. Proceeds from sale of cushion are classified as operating activities in the consolidated statements of cash flows since the predominant source of cash flows for natural gas purchases and sales are operating in nature.
	Repairs, maintenance and renewals that do not provide future economic benefits to the assets are expensed as incurred. Interest costs for the construction or development of long-lived assets held by operational entities are capitalized and amortized over the related asset's estimated useful life.
	Asset retirement obligations
	Niska Partners records a liability for an asset retirement obligation when the legal obligation to retire the asset has been incurred with an offsetting increase to the carrying value of the related tangible long-lived asset. The recognition of an asset retirement obligation requires that management make numerous estimates, assumptions and judgments regarding such factors as the estimated probabilities, amounts and timing of settlements, the credit-adjusted risk-free rate, inflation rates and future advances in technology. In periods subsequent to initial measurement of the liability, the Company must recognize changes in the liability resulting from the passage of time and revisions to either the timing or the amount of the original estimate of undiscounted cash flows. Over time, the liability is accreted to its future value, and the capitalized cost is depreciated over the useful life of the related asset. Accretion of the asset retirement obligations due to the passage of time is recorded as an expense in the statement of earnings. Upon settlement of the liability, the Company either settles the obligation for its recorded amount or incurs a gain or loss.
	Netting of certain balance sheet accounts
	Certain risk management assets and liabilities and certain accrued gas sales and purchases are presented on a net basis in the balance sheet when all of the following exist: (i) Niska Partners and the other party owe the other a determinable amount; (ii) the Company has the right to set off the amount owed with the amount owed by the other party; (iii) Niska Partners intends to set off; and (iv) the right of setoff is enforceable by law.
	Leases
	Niska Partners determines a lease to be an operating or capital lease based upon the terms of the lease, estimated fair value of the leased assets, estimated life of the leased assets, and the contractual minimum lease payments as defined within the lease agreements. If the Company concludes that it has substantively all of the risks of ownership of a leased property and therefore is deemed the owner of the property for accounting purposes, it records an asset and related obligations under capital lease at the lower of the present value of the minimum lease payments or the fair value of the asset.
	Impairment of long-lived assets
	Niska Partners evaluates whether events or circumstances have occurred that indicate that long-lived assets may not be recoverable or that the remaining useful life may warrant revision. When such events or circumstances are present, the Company assesses the recoverability of long-lived assets by determining whether the carrying value will be recovered through the expected undiscounted future cash flows. In the event that the sum of the expected future cash flows resulting from the use of the asset is less than the carrying value of the asset, an impairment loss equal to the excess of the asset's carrying value over its fair value is recorded.
	Goodwill and other intangible assets
	Niska Partners accounts for business acquisitions using the purchase method of accounting and, accordingly, the assets and liabilities of the acquired entities are recorded at their estimated fair values at the date of acquisition. The excess of the purchase price over the fair value of the net assets acquired is attributed to goodwill.
	Goodwill is not amortized and is re-evaluated on an annual basis or more frequently if events or changes in circumstances indicate that the asset might be impaired. Goodwill is tested for impairment between annual tests if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value. These events or circumstances could include a significant change in the business climate, legal factors, operating performance indicators, competition, sale or disposition of a significant portion of the business or other factors.
	To re-evaluate goodwill for impairment, the Company has the option to first assess qualitative factors to determine whether it is more likely than not that goodwill is impaired. The result of the qualitative assessment would be used as a basis in determining whether it is necessary to perform the quantitative impairment test. The performance of the quantitative impairment test involves a two-step process. The first step involves comparing the fair values of the applicable reporting units with their aggregate carrying values, including goodwill. If the carrying amount exceeds the fair value of the reporting unit, the Company performs the second step of the goodwill impairment test to determine the amount of impairment loss. The second step of the goodwill impairment test involves comparing the implied fair value of the affected reporting unit's goodwill with the carrying value of that goodwill.
	Other intangible assets represent contractual rights obtained in connection with a business combination that had favorable contractual terms relative to market as of the acquisition date.
	Intangible assets representing customer contracts and relationships are amortized over their useful lives. These assets are reviewed for impairment as impairment indicators arise. When such events or circumstances are present, the recoverability of long-lived assets is assessed by determining whether the carrying value will be recovered through the expected undiscounted future cash flows. In the event that the sum of the expected future cash flows resulting from the use of the asset is less than the carrying value of the asset, an impairment loss equal to the excess of the asset's carrying value over its fair value is recorded.
	Pipeline rights of way are formal agreements granting rights of way in perpetuity and are not subject to amortization but are subject to an annual impairment test.
	Risk management activities
	The Company uses natural gas derivatives and other financial instruments to manage its exposure to changes in natural gas prices, and foreign exchange rates. These financial assets and liabilities, which are recorded at fair value on a recurring basis, are included in one of three categories based on a fair value hierarchy with realized and unrealized gains (losses) recognized in net earnings (loss) for the period (see Note 13).
	The fair value of the Company's derivative risk management contracts are recorded as a component of risk management assets and liabilities, which are classified as current or non-current assets or liabilities based upon the anticipated settlement date of the contracts.
	Foreign currency translation
	The functional and reporting currency of the Company is the U.S. dollar. Non-U.S. dollar denominated monetary items are translated into U.S. dollars at the rate of exchange in effect at the balance sheet date. Non-U.S. dollar denominated non-monetary items are translated to U.S. dollars at the exchange rate in effect when the transaction occurred. Revenues and expenses denominated in foreign currencies are translated at the actual exchange rate or average exchange rate in effect during the period. Foreign exchange gains or losses on translation are included as a component of net earnings (loss) for the period.
	Deferred financing costs
	Deferred financing costs relate to costs incurred on the issuance of debt, and are amortized over the term of the related debt to interest expense using the effective interest method for costs related to the senior notes offering. Deferred financing costs incurred on the revolving credit facilities are amortized on a straight line basis. Any remaining unamortized deferred financing costs related to repurchased senior notes or modified revolving credit facility agreements are written off on the dates of redemption or modification.
	Income taxes
	The Company is not a directly taxable entity. Income taxes on its income are the responsibility of the individual unitholders and accordingly, have not been recorded in the consolidated financial statements. However, Niska Partners does own corporate subsidiaries which are taxable corporations subject to Canadian federal and provincial income taxes and which are included in the consolidated financial statements.
	Income taxes on the Canadian corporate subsidiaries are determined using the asset and liability method, which results in deferred income tax assets and liabilities arising from temporary differences. Temporary differences are differences between the tax basis of assets and liabilities and their reported amounts in the financial statements that will result in taxable or deductible amounts in future years. This method requires the effect of tax rate changes on current and accumulated deferred income taxes to be reflected in the period in which the rate change was enacted. The asset and liability method also requires that deferred income tax assets be reduced by a valuation allowance unless it is more likely than not that the assets will be realized.
	The Company's policy is to recognize accrued interest and penalties on accrued tax balances as components of interest expense.
	Unit-based performance plan
	Niska Partners' compensation committee approves the awards of unit-based performance plans to certain key employees. These awards include both time and performance-based components.
Unit-based awards are classified as liabilities when expected to be settled in cash or when the Company has the option to settle in cash or equity. This accounting treatment has resulted from the Company's historical practice of choosing to settle this type of award in cash. When awards are classified as liabilities, the fair value of the units granted is determined on the date of grant and is re-measured at each reporting period until the settlement date. The fair value at each re-measurement date is equal to the settlement expected to be incurred based on the anticipated number of units vested, adjusted for (i) the passage of time and (ii) the payout threshold associated with the performance targets which the Company expects to achieve compared to its established peers. The pro-rata number of units vested is calculated as the number of performance awards multiplied by the percentage of the requisite service period.
Unit-based awards that are expected to be settled in units are classified as equity. The fair value of the units granted is determined on the date of grant and is amortized to equity using the straight-line method over the vesting period. Each equity settled award permits the holder to receive one common unit on the vesting date.
All of the granted unit-based awards have the right to receive additional units in lieu of cash distributions paid on the outstanding units. The typical vesting period ranges from two to three years from the date of grant.

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Mar. 31, 2015
Recent Accounting Pronouncements
Recent Accounting Pronouncements
	3. Recent Accounting Pronouncements
	In July 2013, the Financial Accounting Standards Board ("FASB") issued guidance which requires entities to present unrecognized tax benefits or portions of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for a net operating loss carry forward, a similar tax loss, or a tax credit carry forward except when (1) a net operating loss carry forward, a similar tax loss, or a tax credit carry forward is not available as of the reporting date under the governing tax law to settle taxes that would result from the disallowance of the tax position; and (2) the entity does not intend to use the deferred tax asset for this purpose, provided that tax law permits a choice. If either of these conditions exists, entities should present an unrecognized tax benefit in the financial statements as a liability and should not net the unrecognized tax benefit with a deferred tax asset. The Company adopted this guidance on April 1, 2014 and adoption did not have a material impact on the Company's financial position, result of operations or cash flows.
	In May 2014, the FASB adopted Accounting Standards Update No. 2014-09 ("ASU 2014-09"), Revenue from Contracts with Customers. Under the new rules, companies will recognize revenue when it transfers promised goods or services to customers in an amount that reflects what it expects to receive in exchange for the goods or services. The rules also require more detailed disclosures related to the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. These rules are effective for interim and annual periods in fiscal years beginning after December 15, 2016. Management is currently evaluating the impact of the pending adoption of ASU 2014-09 on the Company's consolidated financial statements and has not yet determined the method by which it will adopt the standard in 2017.
	In August 2014, the FASB adopted Accounting Standards Update No. 2014-15 Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. The new accounting guidance requires management to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity's ability to continue as a going concern within one year after the date that the financial statements are issued. It also requires increased disclosures if management determines that substantial doubt about the entity's ability to continue as a going concern exist. The Company will adopt this guidance on April 1, 2017, and Management believes that its impact will not be material to the Company's results of operations and amount of disclosures.
	In April 2015, the FASB adopted Accounting Standards Update No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. Under the new accounting guidance, companies are required to present debt issuance costs related to a recognized debt liability as a direct deduction from the carrying amount of the related debt, consistent with debt discounts. The Company will adopt this guidance on April 1, 2016 on a retrospective basis, wherein the balance sheet of each individual date presented will be adjusted to show long-term debt net of related issue costs.

Property_Plant_and_Equipment

Property, Plant and Equipment	12 Months Ended
Property, Plant and Equipment	Mar. 31, 2015
Property, Plant and Equipment
Property, Plant and Equipment	4. Property, Plant and Equipment
	Property, plant and equipment are comprised of the following:

		As at March 31, 2015
		Cost		Accumulated			Net Book
		Cost		Depreciation			Value
	Cushion	$	356,655	$	—		$	356,655
	Pipelines and measurement		296,669		(102,885	)		193,784
	Wells		127,297		(45,004	)		82,293
	Facilities		276,892		(92,473	)		184,419
	Computer hardware and software		4,293		(3,440	)		853
	Construction in progress, including projects under development		1,486		—			1,486
	Office furniture, equipment and other		2,515		(1,538	)		977

		$	1,065,807	$	(245,340	)	$	820,467




		As at March 31, 2014
		Cost		Accumulated			Net Book
		Cost		Depreciation			Value
	Cushion	$	421,404	$	—		$	421,404
	Pipelines and measurement		296,671		(92,687	)		203,984
	Wells		126,694		(40,700	)		85,994
	Facilities		272,645		(79,028	)		193,617
	Computer hardware and software		4,225		(3,087	)		1,138
	Construction in progress, including projects under development		1,063		—			1,063
	Office furniture, equipment and other		2,473		(1,399	)		1,074

		$	1,125,175	$	(216,901	)	$	908,274


	Facilities include cost and accumulated depreciation of assets under capital lease of $14.2 million and $6.6 million as of March 31, 2015, respectively, and $14.2 million and $4.5 million as of March 31, 2014, respectively. It also includes the cost and accumulated depreciation of major overhauls of engines and compressors of $2.4 million and $0.1 million, respectively, at March 31, 2015, and $0.3 million and $ nil, respectively, at March 31, 2014.
	On July 15, 2014, Niska Partners entered into an agreement with Talisman Energy Canada whereby, for an immaterial amount of consideration, the Company acquired the necessary reservoir, storage and land interests to develop a natural gas storage facility in northwestern Alberta, Canada. If developed, the project will have a working gas storage capacity of approximately 55 billion cubic feet ("Bcf"), expandable up to 70 Bcf (the "Sundance Project"). The requisite underlying regulatory approvals have been obtained from the Alberta Energy Regulator and the Sundance Project has significant access to pipeline infrastructure and the associated western Canadian markets. Niska Partners has deferred the development of the Sundance Project as of March 31, 2015 due to unfavorable market conditions.
	The Company sold cushion from one of its Canadian facilities and from one of its U.S. facilities, which resulted in losses of $14.9 million during the year ended March 31, 2013.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	12 Months Ended
Goodwill and Other Intangible Assets	Mar. 31, 2015
Goodwill and Other Intangible Assets
Goodwill and Other Intangible Assets	5. Goodwill and Other Intangible Assets
	Goodwill
	During the year ended March 31, 2015, the Company concluded that a number of factors, including the continued narrow difference between summer and winter prices in the natural gas futures market, combined with a significant reduction in natural gas price volatility and a significant decline in the Company's equity market capitalization were impairment indicators. We made this determination because these factors had a material negative effect on our current financial performance and our expected performance in future years. Accordingly, we performed an impairment test which resulted in a charge of $245.6 million related to the goodwill valuation of our AECO HubTM and NGPL reporting units.
	The goodwill impairment test is performed at a reporting unit level. Reporting units are identified and distinguished based on how the associated business is managed, taking into consideration the nature of services offered, the types of customer contracts entered into and the nature of the economic and regulatory environment. Niska Partners has four reporting units (its AECO HubTM facility in Alberta, its Wild Goose facility in California, its Salt Plains facility in Oklahoma and its contractual capacity on the Natural Gas Pipeline of America ("NGPL") system). These reporting units are aggregated into one operating segment for financial reporting purposes. Prior to the impairment test, Niska Partners' total goodwill of $245.6 million was recorded at the AECO HubTM facility ($228.0 million) and the NGPL capacity ($17.6 million). There was no goodwill recorded at the Wild Goose or Salt Plains facilities.
	The performance of the impairment test involves a two step process. The first step determines whether an impairment exists by comparing the fair value of a reporting unit with its carrying amount, including goodwill. If the estimated fair value of the reporting unit exceeds its carrying amount, no impairment is necessary. If the carrying amount of a reporting unit exceeds its estimated fair value, the second step measures the amount of impairment by comparing the implied fair value of the reporting unit goodwill with the carrying amount of that goodwill. An entity assigns the fair value of a reporting unit to all of the assets and liabilities of that unit as if the reporting unit had been acquired in a business combination. The excess of the fair value of a reporting unit over the amounts assigned to its assets and liabilities is the implied fair value of goodwill.
	The Company determined the fair value of the AECO HubTM and NGPL reporting units using a combination of the present value of future cash flows method and the comparable transactions method. The present value of future cash flows was estimated using: (i) discrete financial forecasts, which rely on management's estimates of revenue, expenses and volumes; (ii) long-term natural gas volatility and seasonal spreads; (iii) long-term average exchange rates between the United States dollar and the Canadian dollar; and (iv) appropriate discount rates. The comparable transactions method analyzed other purchases of similar assets and considered: (i) the anticipated cash flows of the Company determined above; (ii) recent transaction multiples based on anticipated cash flows; and (iii) the similarity of comparable transactions to the Company's facilities. Specifically, the Company used experience and forecasted amounts to estimate cycling volumes and expenses, the future summer to winter spreads which reflects its longer-term outlook, and extrinsic values consistent with those achieved in the business to estimate future revenue. The Company also used a comparable transaction multiple consistent with recent transactions for depleted reservoir storage facility acquisitions (the type of facilities comparable to the Company's AECO HubTM facility). Both the AECO HubTM and the NGPL reporting units failed step one of the goodwill impairment test; therefore, the second step of impairment test was performed.
	In step two, the Company compared the implied fair value of each reporting unit's goodwill with the respective carrying amount of that goodwill. Under step two of the impairment test, significant assumptions in measuring the fair value of the assets and liabilities included: (i) the replacement cost, depreciation and obsolescence and useful lives of property, plant and equipment; and (ii) the present value of incremental cash flows attributable to certain intangible assets. Based on the step two analysis, the Company determined its goodwill balance was fully impaired.
	The allocation of goodwill balances and related impairment charges by reporting unit consists of the following:

		AECO			NGPL			Total
		HubTM			Leased
					Capacity
	Balance, April 1, 2014	$	228,004		$	17,600		$	245,604
	Impairment charges		(228,004	)		(17,600	)		(245,604	)

	Balance, March 31, 2015	$	—		$	—		$	—


	The Company also considered the goodwill impairment an indicator of impairment related to the long-lived assets associated with its facilities. Accordingly, these assets were evaluated for impairment and management concluded that no impairment of other long-lived assets had occurred.
	Other intangible assets
	Information regarding the Company's intangible assets is included in the following table:

		As at March 31,
		2015			2014
	Customer contracts and relationships, beginning of the year	$	165,080		$	163,073
	Additions		—			2,007
	Less accumulated amortization		(141,521	)		(117,888	)

	Customer contracts and relationships, end of the year		23,559			47,192
	Pipeline rights of way		18,270			18,270

		$	41,829		$	65,462


	Customer contracts and relationships are amortized over the term of the respective contracts, being 1 to 9 years remaining at March 31, 2015. The following table presents an estimate of future amortization expense based upon the Company's intangible assets at March 31, 2015:

	For the fiscal year ending:	Amortization
	For the fiscal year ending:	Expense
	March 31, 2016	$	5,977
	March 31, 2017		7,513
	March 31, 2018		3,558
	March 31, 2019		3,341
	March 31, 2020 and thereafter		3,170
	Amortization expense for customer contacts and relationships for each of the three years ended March 31, 2015 is presented in Note 16.

Deferred_Financing_Costs

Deferred Financing Costs	12 Months Ended
Deferred Financing Costs	Mar. 31, 2015
Deferred Financing Costs
Deferred Financing Costs	6. Deferred Financing Costs
	Information regarding the Company's deferred financing costs consists of the following:

		As at March 31,
		2015			2014
	Deferred financing costs, beginning of the year	$	20,078		$	25,377
	Additions		13			11,696
	Write-off due to extinguishment of debt		—			(16,995	)

	Deferred financing costs, end of the year		20,091			20,078

	Accumulated amortization, beginning of the year		(5,438			(10,957
	Accumulated amortization, beginning of the year		(5,438	)		(10,957	)
	Amortization recognized as interest (see Note 17)		(3,652	)		(3,354	)
	Write-off due to extinguishment of debt		—			8,873

	Accumulated amortization, end of the year		(9,090	)		(5,438	)

	Net book value	$	11,001		$	14,640


	Life in years		2 - 4			3 - 5

Debt

Debt	12 Months Ended
Debt	Mar. 31, 2015
Debt
Debt	7. Debt
	At March 31, 2015 and 2014 the Company's debt consisted of the following:

			As at March 31,
			2015			2014
	6.50% Senior Notes due 2019		$	575,000		$	575,000
	Revolving credit facilities			193,500			119,500

				768,500			694,500
	Less: portion classified as current			(193,500	)		(119,500	)

			$	575,000		$	575,000


	Senior Notes due 2019
	In March 2014, Niska Partners completed a private placement of senior unsecured notes due 2019 (the "6.50% Senior Notes" or "Notes") through its subsidiaries Niska Gas Storage Finance Corp. and Niska Gas Storage Canada ULC (together, the "Issuers"). Net proceeds from the offering of approximately $563.3 million, after deducting underwriters' discounts and fees, along with borrowings under our asset-based revolving credit facilities, were used to redeem the then outstanding principal amount of $643.8 million of the 8.875% Senior Notes due 2018. Including a call premium of approximately $28.6 million and the write-off of unamortized deferred financing costs of $8.1 million, the Company recognized a loss of $36.7 million, which was recorded as a loss on extinguishment of debt in fiscal 2014. These losses were measured based on the amount paid as well as on the carrying value of the redeemed 8.875% Senior Notes, which included unamortized debt issue costs on the dates of redemption. The related accrued interest paid was recorded in interest expense. Costs directly related to the issuance of the new Notes were capitalized as deferred financing costs and are amortized to interest expense over the term of the debt.
	On December 3, 2014, the U.S. Securities and Exchange Commission accepted and made effective the Company's exchange offer whereby holders of the 6.50% Senior Notes were permitted to exchange such Senior Notes for new freely transferable Senior Notes. The terms of the new units are identical to the units issued on March 17, 2014 except that the new units are registered under the Securities Act and generally do not contain restriction on transfer. The exchange offer was completed on January 7, 2015 and substantially all the holders of the Senior Notes accepted the offer.
	The 6.50% Senior Notes are senior unsecured obligations which are: (1) effectively junior to Niska Partners' secured obligations to the extent of the value of the collateral securing such debt; (2) equal in right of payment with all existing and future senior unsecured indebtedness of the Company; and (3) senior in right of payment to any future subordinated indebtedness of Niska Partners. The 6.50% Senior Notes are fully and unconditionally guaranteed by Niska Partners and certain of its direct and indirect subsidiaries on a senior unsecured basis, and are: (1) effectively junior to each guarantor's secured obligations; (2) equal in right of payment with all existing and future senior unsecured indebtedness of each guarantor; and (3) senior in right of payment to any future subordinated indebtedness of each guarantor. Interest on the 6.50% Senior Notes is payable semi-annually on October 1 and April 1, and will mature on April 1, 2019. As of March 31, 2015, the estimated fair market value of the Notes was $432.7 million.
	Prior to October 1, 2016, the Company has the option to redeem up to 35% of the aggregate principal amount of the 6.50% Senior Notes using net cash proceeds from certain equity offerings at a price of 106.50% plus accrued and unpaid interest. The Company may also redeem all or a part of the 6.50% Senior Notes at redemption prices (expressed as percentages of principal amount) equal to 103.25% during the twelve-month period beginning on October 1, 2016, 101.625% during the twelve-month period beginning on October 1, 2017 and at par beginning on October 1, 2018, plus accrued and unpaid interest. The Company is not required to make mandatory redemptions or sinking fund payments with respect to the 6.50% Senior Notes.
	The indenture governing the 6.50% Senior Notes limits Niska Partners' ability to pay distributions in respect of, repurchase or pay dividends on its membership interests (or other capital stock) or make other restricted payments.
	The indenture does not prohibit certain types or amounts of restricted payments, including a general basket of $75.0 million of restricted payments.
	The indenture governing the Notes contains certain other covenants that, among other things, limit Niska Partners and certain of its subsidiaries' ability to:

		•	incur additional debt or issue certain capital stock;
		•	pay dividends on, repurchase or make distributions in respect of its capital stock or repurchase or retire subordinated indebtedness;
		•	make certain investments;
		•	sell assets;
		•	create liens;
		•	consolidate, merge, sell or otherwise dispose of all or substantially all of its assets;
		•	enter into certain transactions with its affiliates; and
		•	permit restrictions on the ability of its subsidiaries to make distributions.
	The occurrence of events involving the Company or certain of its subsidiaries may constitute an event of default under the indenture. Such events include failure to pay interest, principal, or the premium on the notes when due; failure to comply with the merger, asset sale or change of control covenants; certain defaults on other indebtedness; and certain insolvency proceedings. In the case of an event of default, the holders of the notes are entitled to remedies, including the acceleration of payment of the notes by request of the holders of at least 25% in aggregate principal amount of the notes, and any action by the trustee to collect payment of principal, interest or premium in arrears. Upon the occurrence of a change of control together with a decrease in the ratings of the 6.50% Senior Notes by either Moody's or S&P by one or more gradations within 90 days of the change of control event, Niska Partners must offer to repurchase the Notes at 101% of the principal amount of the notes to be repurchased, plus accrued and unpaid interest, if any, to the date of repurchase.
	The Company's ability to repurchase the 6.50% Senior Notes upon a change of control will be limited by the terms of its debt agreements, including its asset-based revolving credit facilities. In addition, the Company cannot assure that it will have the financial resources to repurchase the Notes upon a change of control.
	Revolving credit facilities
	Niska Partners, through its subsidiaries, Niska Gas Storage US, LLC and AECO Gas Storage Partnership, has senior secured asset-based revolving credit facilities consisting of a U.S. revolving credit facility and a Canadian revolving credit facility, (collectively as "Credit Facilities") both of which are governed by a credit agreement (the "Credit Agreement" or the "$400 million Credit Agreement"). These Credit Facilities provide for revolving loans and letters of credit in an aggregate principal amount of up to $200.0 million for each of a U.S. revolving credit facility and a Canadian revolving credit facility. Subject to certain conditions, each of the U.S. revolving credit facility and the Canadian revolving credit facility may be expanded up to a total of $100.0 million in additional commitments, and the commitments in each facility may be reallocated on terms and according to procedures to be determined. Loans under the U.S. revolving facility will be denominated in U.S. dollars and loans under the Canadian revolving facility may be denominated, at Niska Partners' option, in either U.S. or Canadian dollars. The revolving credit facilities mature on June 29, 2016.
	Borrowings under the Credit Facilities are limited to a borrowing base calculated as the sum of specified percentages of eligible cash and cash equivalents, eligible accounts receivable, the net liquidating value of hedge positions in broker accounts, eligible inventory, issued but unused letters of credit, and certain fixed assets minus the amount of any reserves and other priority claims. Borrowings will bear interest at prevailing market rates, which (1) in the case of U.S. dollar loans can be either fixed rate plus an applicable margin or, at the Company's option, a base rate plus an applicable margin, and (2) in the case of Canadian dollar loans can be either the bankers' acceptance rate plus an applicable margin or, at the Company's option, a prime rate plus an applicable margin. The credit agreement provides that Niska Partners may borrow only up to the lesser of the level of the then current borrowing base or the committed maximum borrowing capacity, which is currently $400.0 million. As of March 31, 2015, the borrowing base collateral totaled $294.4 million.
	Obligations under the $400.0 million Credit Agreement are guaranteed by Niska Partners and all of the Company's direct and indirect wholly owned subsidiaries (subject to certain exceptions) and secured by a lien on substantially all of the Company's and its direct and indirect subsidiaries' current and fixed assets (subject to certain exceptions). Certain fixed assets will only be required to be part of the collateral to the extent such fixed assets are included in the borrowing base under the Credit Facilities. The aggregate borrowing base under the Credit Facilities includes $150.0 million (the "PP&E Amount") due to a first-priority lien on fixed assets granted to the lenders. The PP&E Amount will be reduced on a dollar-for-dollar basis upon the release of fixed assets having a value in excess of $50.0 million from such liens.
	The $400 million Credit Agreement contains limitations on Niska Partners' ability to incur additional debt or to pay distributions in respect of, repurchase or pay dividends on its membership interests (or other capital stock) or make other restricted payments. These limitations are similar to those contained in the indenture governing the 6.50% Senior Notes, but contain certain substantive differences. As of March 31, 2015, Niska Partners was in compliance with all covenant requirements under the 6.50% Senior Notes and the $400 million Credit Agreement.
	The following fees are applicable under each revolving credit facility: (1) an unused revolver fee based on the unused portion of the respective revolving credit facility; (2) a letter of credit participation fee on the aggregate stated amount of each letter of credit equal to the applicable margin for LIBOR loans or bankers' acceptance loans, as applicable; and (3) certain other customary fees and expenses of the lenders and agents. The Company is required to make prepayments under the revolving credit facilities at any time when, and to the extent that, the aggregate amount of the outstanding loans and letters of credit under such revolving credit facilities exceeds the lesser of the aggregate amount of commitments in respect of such revolving credit facilities and the applicable borrowing base.
	The $400.0 million Credit Agreement contains customary covenants, including, but not limited to, restrictions on the Company's and its subsidiaries' ability to merge and consolidate with other companies, incur indebtedness, grant liens or security interests on assets subject to security interests under the credit agreement, make acquisitions, loans, advances or investments, pay distributions, sell or otherwise transfer assets, optionally prepay or modify terms of any subordinated indebtedness or enter into transactions with affiliates. The Credit Facilities require the maintenance of a fixed charge coverage ratio of 1.1 to 1.0 at the end of each fiscal quarter when excess availability under both the U.S. revolving credit facility and the Canadian revolving credit facility is less than 15% of the aggregate amount of availability under both revolving credit facilities. Such fixed charge coverage ratio will be tested at the end of each quarter until such time as average excess availability exceeds 15% for thirty consecutive days.
	The $400.0 million Credit Agreement provides that, upon the occurrence of certain events of default, the Company's obligations thereunder may be accelerated and the lending commitments terminated. Such events of default include payment defaults to the lenders, material inaccuracies of representations and warranties, covenant defaults, cross-defaults to other material indebtedness, including the notes, voluntary and involuntary bankruptcy proceedings, material money judgments, material events relating to pension plans, certain change of control events and other customary events of default. As of March 31, 2015, $193.5 million (March 31, 2014—$119.5 million) in borrowings, with a weighted average interest rate of 3.98% (March 31, 2014—3.56%), were outstanding under the Credit Facilities. Issued letters of credit amounted to $5.8 million and $4.8 million as of March 31, 2015 and 2014, respectively.
	Restrictions
	Niska Partners has no independent assets or operations other than its investments in its subsidiaries. Both the 6.50% Senior Notes and the $400.0 million Credit Agreement have been jointly and severally guaranteed by Niska Partners and substantially all of its subsidiaries. Niska Partners' subsidiaries have no significant restrictions on their ability to pay distributions or make loans to Niska Partners, which are prepared and measured on a consolidated basis, and have no restricted assets as of March 31, 2015.
	The Company's principal debt covenant is the fixed charge coverage ratio, which is included in both the Credit Facilities and in the Indenture. When the fixed charge coverage ratio is less than 2.0 times, Niska Partners is restricted in its ability to issue new debt. When the fixed charge coverage ratio is below 1.75 to 1.0, the Company is restricted in its ability to pay distributions. At March 31, 2015, the fixed charge coverage ratio was 1.3 to 1.0 and the Company was subject to the above restrictions.

Obligations_Under_Capital_Leas

Obligations Under Capital Lease	12 Months Ended
Obligations Under Capital Lease	Mar. 31, 2015
Obligations Under Capital Lease
Obligations Under Capital Lease	8. Obligations Under Capital Lease
	The Company leases certain equipment under a lease arrangement for estimated future minimum lease payments of approximately $12.2 million. Niska Partners may purchase the assets after August 15, 2020 for an agreed portion of the acquisition cost. The present value of the minimum future lease payments is based on the total costs incurred by the lessor and has been reflected in the balance sheet as a current and a non-current obligation under capital lease. The underlying obligations are denominated in U.S. dollars, have an imputed interest rate of 3.08% and are owing through the lease maturity in August 2021.
	Following are the future principal and interest payments of obligations under capital lease as of March 31, 2015:

	For the fiscal year ending:
	March 31, 2016	$	1,657
	March 31, 2017		1,657
	March 31, 2018		1,657
	March 31, 2019		1,657
	March 31, 2020		1,657
	March 31, 2021 and thereafter		3,917
	Less: Amount representing interest		(1,276	)

		$	10,926

Accrued_Liabilities

Accrued Liabilities	12 Months Ended
Accrued Liabilities	Mar. 31, 2015
Accrued Liabilities
Accrued Liabilities	9. Accrued Liabilities
	Niska Partners' accrued liabilities consist of the following:

		As at March 31,
		2015		2014
	Accrued interest	$	21,411	$	2,037
	Accrued gas purchases		13,917		75,454
	Employee-related accruals		2,369		22,315
	Other accrued liabilities		9,989		11,312

		$	47,686	$	111,118

Asset_Retirement_Obligations

Asset Retirement Obligations	12 Months Ended
Asset Retirement Obligations	Mar. 31, 2015
Asset Retirement Obligations
Asset Retirement Obligations	10. Asset Retirement Obligations
	Niska Partners' asset retirement obligations relate to the plugging and abandonment of the storage facilities and wells at the end of their estimated useful economic lives. At March 31, 2015, the estimated undiscounted cash flows required to settle the asset retirement obligations were approximately $58.5 million, calculated using an inflation rate of 2% per annum. The estimated liability at March 31, 2015 was $2.3 million after discounting the estimated cash flows at a rate of 8% per annum. At March 31, 2015, the expected timing of payment for settlement of the obligations is 42 years.

		As at March 31,
		2015			2014
	Balance, beginning of the year	$	1,975		$	2,007
	Additions		22			—
	Accretion		500			107
	Effect of foreign exchange translation		(189	)		(139	)

	Balance, end of the year	$	2,308		$	1,975

Income_Taxes

Income Taxes	12 Months Ended
Income Taxes	Mar. 31, 2015
Income Taxes
Income Taxes	11. Income Taxes
	The components of the Company's earnings (loss) before income taxes follow:

			Year ended March 31,
			2015			2014			2013
	Domestic		$	6,506		$	16,844		$	(493	)
	Foreign			(388,818	)		(36,057	)		(62,050	)

			$	(382,312	)	$	(19,213	)	$	(62,543	)


	Total income tax expense (benefit) differed from the amounts computed by applying the tax rate to earnings (loss) before income taxes as a result of the following:

			Year ended March 31,
			2015			2014			2013
	Earnings (loss) before taxes		$	(382,312	)	$	(19,213	)	$	(62,543	)
	U.S. federal corporate statutory rate			35	%		35	%		35	%

	Expected tax benefits			(133,809	)		(6,725	)		(21,890	)
	Non-deductible expense related to asset impairment			57,001
	Non-deductible expense related to asset impairment			57,001			—			—
	Canadian statutory tax rate differences			39,056			3,559			6,145
	Adjustments and assessments			2,592			(690	)		(4,796	)
	Change in valuation allowance			2,314			(1,248	)		(452	)
	Earnings (loss) of non-taxable entities			(1,925	)		(6,296	)		1,377
	Non-deductible expenses and other			3,115			1,144			674

	Income tax benefit		$	(31,656	)	$	(10,256	)	$	(18,942	)


	The Company is not a taxable entity in the United States. Income taxes on its income are the responsibility of individual unitholders and have accordingly not been recorded in the consolidated financial statements. Niska Partners has Canadian corporate subsidiaries, which are taxable corporations subject to income taxes, and are included in the consolidated financial statements.
	As at March 31, 2015, Niska Partners' Canadian subsidiaries had accumulated non-capital losses of approximately $76.4 million (March 31, 2014—$76.2 million) that can be carried forward and applied against future taxable income. These non-capital losses have resulted in deferred income tax assets of $19.0 million (March 31, 2014—$18.4 million). Additionally, Niska Partners' Canadian subsidiaries had recognized deferred income tax assets related to capital losses of $33.8 million at March 31, 2015 (March 31, 2014—$18.9 million). These capital losses represent $4.2 million (March 31, 2014—$2.4 million) of deferred tax assets, of which $4.2 million (March 31, 2014—$2.4 million) have been offset by valuation allowances due to the uncertainty of their realization. Of the total tax assets related to losses, $0.5 million will begin to expire at the end of 2031.
	For the year ended March 31, 2015, Niska Partners recognized $0.1 million (March 31, 2014—$ nil; March 31, 2013—$ nil) of potential interest and penalties associated with uncertain tax positions. The Company files income tax returns in the U.S. federal jurisdiction, various state jurisdictions and other foreign jurisdictions. The Company is subject to income tax examinations for the fiscal years ended 2007 through 2015 in most jurisdictions.
	Deferred income tax assets and liabilities reflect the tax effect of differences between the basis of assets and liabilities for book and tax purposes. The tax effect of temporary differences that give rise to significant components of the deferred income tax liabilities and deferred income tax assets are presented below:

			As at March 31,
			2015			2014
	Deferred income tax assets:
	Non-capital loss carry forwards		$	18,959		$	18,434
	Risk management liabilities			19,919			33,386
	Capital losses			4,223			2,358
	Deferred financing costs			4,006			6,890
	Other			2,774			2,403

				49,881			63,471
	Valuation allowance			(7,173	)		(4,004	)

	Total deferred income tax assets		$	42,708		$	59,467


	Deferred income tax liabilities:
	Property, plant and equipment		$	99,628		$	114,298
	Risk management assets			24,202			17,049
	Intangible assets			9,510			15,137
	Partnership deferral income			—			37,499
	Other			19			535

	Total deferred income tax liabilities			133,359			184,518

	Net deferred income tax liabilities		$	90,651		$	125,051


	The classification of net deferred income tax liabilities recorded on the balance sheets is as follows:

		As at March 31,
		2015			2014
Deferred income tax liabilities:
Current		$	2,334		$	5,678
Long-term			88,317			119,373

		$	90,651		$	125,051


Uncertain Income Tax Positions
When accounting for uncertainty in income taxes, a company recognizes a tax benefit in the financial statements for an uncertain tax position if management's assessment is that the position is "more likely than not" (i.e. a likelihood greater than fifty percent) to be allowed by the tax jurisdiction based solely on the technical merits of the position. The term "tax position" refers to a position in a previously filed tax return or a position expected to be taken in a future tax return that is reflected in measuring current or deferred income tax assets and liabilities for interim or annual periods.
The following table indicates the changes to the Company's unrecognized tax benefits for the years ended March 31, 2015 and 2014. The term "unrecognized tax benefits" refers to the differences between a tax position taken or expected to be taken in a tax return and the benefit measured and recognized in the financial statements. Interest and penalties are not included.

		As at March 31,
		2015			2014
Balance at beginning of the year		$	1,735		$	1,160
Additions based on tax positions taken in the current year			—			375
(Reductions) additions based on tax positions taken in a prior year			(205	)		200

Balance at end of the year		$	1,530		$	1,735


Substantially all of the $1.5 million of unrecognized tax benefits at March 31, 2015, would have an impact on the effective tax rate if subsequently recognized.
The Company engages in ongoing discussions with tax authorities regarding the resolution of tax matters in various jurisdictions. Both the outcome of these tax matters and the timing of the resolution and/or closure of the tax audits are highly uncertain. It is management's assessment that no unrecognized tax benefits will be recognized within the next twelve months.

Risk_Management_Activities_and

Risk Management Activities and Financial Instruments	12 Months Ended
	Mar. 31, 2015
Risk Management Activities and Financial Instruments
Risk Management Activities and Financial Instruments	12. Risk Management Activities and Financial Instruments
	Risk management overview
	The Company has exposure to commodity price, foreign currency, counterparty credit, interest rate, and liquidity risk. Risk management activities are tailored to the risk they are designed to mitigate.
	Commodity price risk
	As a result of its natural gas inventory, Niska Partners is exposed to risks associated with changes in price when buying and selling natural gas across future time periods. To manage this risk and reduce variability of cash flows, the Company utilizes a combination of financial and physical derivative contracts, including forwards, futures, swaps and option contracts. The use of these contracts is subject to the Company's risk management policies. Niska Partners has not elected hedge accounting treatment and therefore changes in fair value are recorded directly into earnings (loss).
	Forwards and futures are contractual agreements to purchase or sell a specific financial instrument or natural gas at a specified price and date in the future. The Company enters into forwards and futures to mitigate the impact of price volatility. In addition to cash settlement, exchange traded futures may also be settled by physical delivery of natural gas.
	Swap contracts are agreements between two parties to exchange streams of payments over time according to specified terms. Swap contracts require receipt of payment for the notional quantity of the commodity based on the difference between a fixed price and the market price on the settlement date. The Company enters into commodity swaps to mitigate the impact of changes in natural gas prices.
	Option contracts are contractual agreements to convey the right, but not the obligation, for the purchaser of the option to buy or sell a specific physical or notional amount of a commodity at a fixed price, either at a fixed date or at any time within a specified period. Niska Partners enters into option agreements to mitigate the impact of changes in natural gas prices.
	To limit its exposure to changes in commodity prices, Niska Partners enters into purchases and sales of natural gas inventory and concurrently matches the volumes in these transactions with offsetting derivative contracts. To be in compliance with its risk policy, Niska Partners is required to limit its exposure of unmatched volumes of proprietary current natural gas inventory to an aggregate overall limit of 8.0 billion cubic feet ("Bcf"). As at March 31, 2015, 47.2 Bcf of natural gas inventory was offset, representing 98.6% of total current inventory. The volume of inventories as of March 31, 2015 and 2014 which were economically hedged using each type of contract were as follows:

		As at March 31,
		2015	2014
	Forwards	1.5 Bcf	(1.4 Bcf)
	Futures	46.0 Bcf	20.1 Bcf
	Swaps	(0.3 Bcf)	(0.3 Bcf)

		47.2 Bcf	18.4 Bcf


	Counterparty credit risk
	Niska Partners is exposed to counterparty credit risk on its trade and accrued accounts receivable and risk management assets. Counterparty credit risk is the risk of financial loss to the Company if a customer fails to perform its contractual obligations. Niska Partners engages in transactions for the purchase and sale of products and services with major companies in the energy industry and with industrial, commercial, residential and municipal energy consumers. Credit risk associated with trade accounts receivable is mitigated by the high percentage of investment grade customers, collateral support of receivables and the Company's ability to take ownership of customer-owned natural gas stored in its facilities in the event of non-payment, as well as through the use of netting agreements that allow for offsetting counterparty receivable and payable balances for certain transactions. During the year ended March 31, 2015, no doubtful accounts expense was recognized as a result of doubtful accounts deemed uncollectable as of March 31, 2015 (March 31, 2014—expense of $0.4 million).
	The Company analyzes the financial condition of counterparties prior to entering into an agreement. Credit limits are established and monitored on an ongoing basis. Management believes based on its credit policies, that the Company's financial position, results of operations and cash flows will not be materially affected as a result of non-performance by any single counterparty. Although the Company relies on a few counterparties for a significant portion of its revenues (Note 23), one counterparty, making up 54%, 56% and 28% of total revenue during the years ended March 31, 2015, 2014 and 2013, is a physical natural gas clearing and settlement facility which requires counterparties to post margin deposits reducing the risk of default.
	Exchange traded futures and options comprise approximately 69.0% of Niska Partners' commodity risk management assets at March 31, 2015. These exchange traded contracts have minimal credit exposure as the exchanges guarantee that every contract will be margined on a daily basis. In the event of any default, Niska Partners' account on the exchange would be absorbed by other clearing members. Because every member posts an initial margin, the exchange can protect the exchange members if or when a clearing member defaults.
	Included in the fair value of energy contracts at March 31, 2015 and 2014 are one to five year contracts to sell natural gas to customers in retail markets. Niska Partners has recorded reduction in the fair value of these contracts of $1.7 million at March 31, 2015 (March 31, 2014—$nil), representing an estimate of the expected credit exposure from these counterparties over their contractual lives.
	Interest rate risk
	The Company assesses interest rate risk by continually identifying and monitoring changes in interest rate exposures that may adversely impact expected future cash flows. At March 31, 2015, the Company was exposed to interest rate risk resulting from its variable rate revolving credit facilities, which can be drawn up to $400.0 million. At March 31, 2015, $193.5 million was outstanding on the credit facilities and Niska Partners had exposure to interest rate fluctuations.
	Niska Partners had no interest rate swap or swaption agreements at March 31, 2015 and 2014.
	Liquidity risk
	Liquidity risk is the risk that Niska Partners will not be able to meet its financial obligations as they become due. The Company's approach to managing liquidity risk is to contract a substantial part of its facilities to generate constant cash flow and to ensure that it always has sufficient cash and credit facilities to meet its obligations when due, under both normal and stressed conditions, without incurring unacceptable losses or damage to its reputation. See Note 7 for details of the Company's debt.
	Foreign currency risk
	Foreign currency risk is created by fluctuations in foreign exchange rates. As Niska Partners' Canadian subsidiaries conduct a portion of their activities in Canadian dollars, earnings and cash flows are subject to currency fluctuations. The performance of the Canadian dollar relative to the U.S. dollar could positively or negatively affect earnings. Niska Partners is exposed to cash flow risk to the extent that Canadian currency outflows do not match inflows. Niska Partners enters into currency swaps to mitigate the impact of changes in foreign exchange rates. The notional value of currency swaps as at March 31, 2015 was $19.6 million (March 31, 2014—$13.0 million). These contracts expire on various dates between April 2015 and June 2016. Niska Partners did not elect hedge accounting treatment and therefore changes in fair value are recorded directly into earnings under the optimization revenue caption of the statements of earnings (loss) and comprehensive income (loss).

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
Fair Value Measurements	Mar. 31, 2015
Fair Value Measurements
Fair Value Measurements	13. Fair Value Measurements
	The following table shows the fair values of the Company's risk management assets and liabilities:

	As at March 31, 2015		Energy			Currency			Total
	As at March 31, 2015		Contracts			Contracts			Total
	Short-term risk management assets		$	39,392		$	2,208		$	41,600
	Long-term risk management assets			29,647			1,281			30,928
	Short-term risk management liabilities			(25,560	)		—			(25,560	)
	Long-term risk management liabilities			(20,512	)		(321	)		(20,833	)

			$	22,967		$	3,168		$	26,135




	As at March 31, 2014		Energy			Currency			Total
	As at March 31, 2014		Contracts			Contracts			Total
	Short-term risk management assets		$	18,939		$	2,010		$	20,949
	Long-term risk management assets			4,260			546			4,806
	Short-term risk management liabilities			(18,945	)		(160	)		(19,105	)
	Long-term risk management liabilities			(12,209	)		—			(12,209	)

			$	(7,955	)	$	2,396		$	(5,559	)


	Information about the Company's risk management assets and liabilities that had netting or rights of offset arrangements are as follows:

	As at March 31, 2015		Gross Amounts			Gross Amounts			Net Amounts			Margin			Net
			Recognized			Offset in the			Presented in			Deposits not			Amounts
						Balance Sheet			the Balance			Offset in the
									Sheet			Balance Sheet
	Assets
	Commodity derivatives		$	148,385		$	(79,346	)	$	69,039		$	(50,070	)	$	18,969
	Currency derivatives			5,167			(1,678	)		3,489			—			3,489

	Total assets			153,552			(81,024	)		72,528			(50,070	)		22,458

	Liabilities
	Commodity derivatives			125,418			(79,346	)		46,072			(39,338	)		6,734
	Currency derivatives			1,999			(1,678	)		321			(321	)		—

	Total liabilities			127,417			(81,024	)		46,393			(39,659	)		6,734

	Net		$	26,135		$	—		$	26,135		$	(10,411	)	$	15,724




	As at March 31, 2014		Gross Amounts			Gross Amounts			Net Amounts			Margin			Net
			Recognized			Offset in the			Presented in			Deposits not			Amounts
						Balance Sheet			the Balance			Offset in the
									Sheet			Balance Sheet
	Assets
	Commodity derivatives		$	113,175		$	(89,976	)	$	23,199		$	(15,101	)	$	8,098
	Currency derivatives			2,851			(295	)		2,556			(2,556	)		—

	Total assets			116,026			(90,271	)		25,755			(17,657	)		8,098

	Liabilities
	Commodity derivatives			121,130			(89,976	)		31,154			(21,705	)		9,449
	Currency derivatives			455			(295	)		160			(160	)		—

	Total liabilities			121,585			(90,271	)		31,314			(21,865	)		9,449

Net		$	(5,559	)	$	—		$	(5,559	)	$	4,208		$	(1,351	)


The following amounts represent the Company's expected realization into earnings for derivative instruments, based upon the fair value of these derivatives as of March 31, 2015:

Fiscal year ending March 31,		Energy			Currency			Total
Fiscal year ending March 31,		Contracts			Contracts			Total
2016		$	13,832		$	2,208		$	16,040
2017 and beyond			9,135			960			10,095

		$	22,967		$	3,168		$	26,135


Net realized and unrealized optimization gains and losses from the settlement of risk management contracts are summarized as follows:

		Year ended March 31,
		2015			2014			2013			Classification
Energy contracts
Realized		$	40,787		$	(78,778	)	$	41,304		Optimization, net
Unrealized			30,922			(10,662	)		(90,641	)	Optimization, net
Currency contracts
Realized			2,459			3,177			1,377		Optimization, net
Unrealized			772			1,930			790		Optimization, net

		$	74,940		$	(84,333	)	$	(47,170	)


The carrying amount of cash and cash equivalents, margin deposits, trade receivables, accrued receivables, trade payables and accrued liabilities reported on the consolidated balance sheet approximate fair value.
Fair values have been determined as follows for the Company's assets and liabilities that were accounted for or disclosed at fair value on a recurring and non-recurring basis as of March 31, 2015 and 2014:

As at March 31, 2015		Level 1			Level 2			Level 3			Total
Assets
Commodity derivatives		$	—		$	69,039		$	—		$	69,039
Currency derivatives			—			3,489			—			3,489
Goodwill			—			—			—			—

Total assets		$	—		$	72,528		$	—		$	72,528


Liabilities
Commodity derivatives		$	—		$	46,072		$	—		$	46,072
Currency derivatives			—			321			—			321
Long-term debt			—			432,688			—			432,688

Total liabilities		$	—		$	479,081		$	—		$	479,081




As at March 31, 2014		Level 1			Level 2			Level 3			Total
Assets
Commodity derivatives		$	—		$	23,199		$	—		$	23,199
Currency derivatives			—			2,556			—			2,556

Total assets		$	—		$	25,755		$	—		$	25,755


Liabilities
Commodity derivatives		$	—		$	31,154		$	—		$	31,154
Currency derivatives			—			160			—			160
Long-term debt			—			570,700			—			570,700

Total liabilities		$	—		$	602,014		$	—		$	602,014


The Company's financial assets and liabilities recorded at fair value on a recurring basis have been categorized as Level 2. The determination of the fair value of assets and liabilities for Level 2 valuations is generally based on a market approach. The key inputs used in Niska Partners' valuation models include transaction-specific details such as notional volumes, contract prices, and contract terms as well as forward market prices and basis differentials for natural gas obtained from third-party service providers (typically the New York Mercantile Exchange, or NYMEX). There were no changes in Niska Partners' approach to determining fair value and there were no transfers out of Level 2 during the three-year period ended March 31, 2015.
The fair value of debt is the estimated amount the Company would have to pay to transfer its debt, including any premium or discount attributable to the difference between the stated interest rate and market rate of interest at the balance sheet date. Fair values are supported by observable market transactions when available.
Non-financial assets and liabilities are re-measured at fair value on a non-recurring basis. During the year ended March 31, 2015, the Company wrote down goodwill to its estimated fair value of $nil, which is classified as a Level 3 measurement in the table above. There were no other non-financial assets or liabilities recorded at fair value as of March 31, 2015 and 2014.

Members_Equity

Members' Equity	12 Months Ended
Members' Equity	Mar. 31, 2015
Members' Equity
Members' Equity	14. Members' Equity
	Equity restructuring
	On April 2, 2013, Niska Partners completed an equity restructuring with affiliates of the Carlyle/Riverstone Funds. In the restructuring, all of the Company's 33.8 million subordinated units and previous incentive distribution rights (all of which were owned by the Carlyle/Riverstone Funds) were combined into and restructured as a new class of incentive distribution rights (IDRs). The equity restructuring, which did not require any further consents or approvals, was effective as of the same day. The transaction was unanimously approved by the Company's Board of Directors on the unanimous approval and recommendation of its Conflicts Committee, which is composed solely of independent directors.
	The restructuring permanently eliminated all of the Company's subordinated units and previous incentive distribution rights in return for the IDRs. Prior to completion of the restructuring, the Company would have been required to pay the full minimum quarterly distribution of $0.35 per unit on the subordinated units (requiring additional distributions of approximately $12 million per quarter) prior to increasing the quarterly distribution on common units. Quarterly distributions on the subordinated units were not paid since the quarter ended September 30, 2011.
	The IDRs entitle the Carlyle/Riverstone Funds to receive 48% of any quarterly cash distributions after Niska Partners' common unitholders have received the full minimum quarterly distribution ($0.35 per unit) for each quarter plus any arrearages from prior quarters (of which there are currently none). The previous incentive distribution rights entitled the Carlyle/Riverstone Funds to receive increasing percentages (ranging from 13% to 48%) of incremental cash distributions after the unitholders (both common and subordinated) exceeded quarterly distributions ranging from $0.4025 per unit to $0.5250 per unit. In addition, for a period of five years, and provided that the Carlyle/Riverstone Funds continue to own a majority of both the managing member and the IDRs, the Carlyle/Riverstone Funds will be deemed to own 33.8 million "Notional Subordinated Units" in connection with votes to remove and replace the managing member. These Notional Subordinated Units are not entitled to distributions, but preserve the Carlyle/Riverstone Fund's voting rights with respect to the removal of the managing member.
	Distribution Reinvestment Plan
	Niska Partners filed a registration statement with the SEC to authorize the issuance of up to 7,500,000 common units in connection with a distribution reinvestment plan ("DRIP"). The DRIP provides unitholders of record and beneficial owners of common units a voluntary means by which unitholders can increase the number of common units owned by reinvesting the quarterly cash distributions unitholders would otherwise receive in the purchase of additional common units. This registration statement became effective on July 31, 2013. Common units purchased under the DRIP will come from the Company's authorized but unissued common units or from common units purchased on the open market.
	During the year ended March 31, 2015, Unitholders, substantially all of which were represented by the Carlyle/Riverstone Funds, elected to participate in the DRIP and were issued 2,243,664 common units (March 31,—2014 1,252,815 common units) in lieu of receiving cash distributions of $19.6 million (March 31, 2014—$18.3 million).
	Class D Partnership Units
	On May 7, 2014, Niska Holdings L.P. (the "Sponsor Partnership"), the parent of Holdco (which is the direct and indirect parent of the Company) awarded non-voting Class D Units in the Sponsor Partnership (the "Class D Units") to certain executives. The Class D Units are profits interest awards which have a service condition. As the Class D Units were issued to employees and a director, equity-classified compensation expense has been recorded in the Company's financial statements.
	The Class D Units entitle the holders thereof to 15% of distributions made by the Sponsor Partnership to its Class A unitholders after its Class A unitholders receive distributions made by the Sponsor Partnership after May 17, 2014 in excess of the amount of any capital contributions made by the Class A unitholders after May 17, 2014 plus $331.0 million, each increased by 8% per annum compounded quarterly. The Sponsor Partnership will retain distributions (other than tax distributions) in respect of unvested Class D Units until such Class D Units vest. Of the awarded Class D Units, 20% will vest on May 6, 2015. The remaining unvested units will vest at a rate of 5% on the last day of each fiscal quarter during the period commencing on June 30, 2015 and ending on March 31, 2019. The units have no expiry date provided the employee remains employed with the Sponsor Partnership, the Company or one or more of their respective subsidiaries. The fair value of the Class D Units is based on an enterprise value, with allocations of that value calculated under the terms of Niska Holdings L.P.'s operating agreement.
	For the year ended March 31, 2015, non-cash compensation expense related to the Class D Units amounted to $0.5 million.
	Limited Liability
	No member of Niska Partners will be obligated personally for any obligation of the Company solely by reason of being a member.
	Under certain circumstances, unitholders may have to repay amounts wrongfully returned or distributed to them. Under Section 18-607 of the Delaware Limited Liability Company Act, or the Delaware Act, Niska Partners may not make a distribution to unitholders if the distribution would cause our liabilities to exceed the fair value of our assets. Delaware law provides that for a period of three years from the date of an impermissible distribution, members who received the distribution and who knew at the time of the distribution that it violated Delaware law will be liable to the limited liability company for the distribution amount. A purchaser of common units will be liable for the obligations of the transferor to make contributions to us that are known to such purchaser at the time it became a member and for unknown obligations if the liabilities could be determined from the Company's Operating Agreement.
	At-The-Market Program
	On October 30, 2013, Niska Partners filed a prospectus supplement with the SEC to authorize an At-The-Market program which allows the issuance of up to $75.0 million in additional common units. The units will be issued pursuant to the Company's Shelf Registration Statement on Form S-3. As of March 31, 2015, the Company had not issued any units under this registration statement.
	Summary of changes in Common and Subordinated units:
	The following is a reconciliation of units outstanding for the period indicated:

			Common			Subordinated			Total
			Unitholders			Unitholders			Total
	Units outstanding at March 31, 2012 and 2013			34,492,245			33,804,745			68,296,990
	Subordinated units cancelled April 2, 2013			—			(33,804,745	)		(33,804,745	)
	Units issued under the DRIP			1,252,815			—			1,252,815

	Units outstanding at March 31, 2014			35,745,060			—			35,745,060
	Units issued under the DRIP			2,243,664			—			2,243,664

	Units outstanding at March 31, 2015			37,988,724			—			37,988,724


	Managing Member units
	The managing member units are held by Niska Gas Storage Management LLC, (the "Managing Member" or the "Manager"), which has a 1.80% managing member interest in Niska Partners. The operating agreement provides that the managing member interest entitles the Manager the right to receive distributions of Available Cash (as defined in the operating agreement) each quarter.
	The Manager has sole responsibility for conducting the Company's business and for managing its operations. Pursuant to the operating agreement, the Manager has delegated the power to conduct Niska Partners' business and manage its operations to the Company's board of directors, of which all of the members are appointed by the Manager.
	The Manager has agreed not to withdraw voluntarily prior to March 31, 2020 subject to certain conditions outlined in the operating agreement. Prior to that time, the Manager may not be removed unless that removal is approved by the vote of the holders of not less than 662/3% of the outstanding units, voting together as a single class, including units held by the Manager and its affiliates. Any removal of the Manager is also subject to the approval of a successor manager by the vote of the holders of a majority of the outstanding common units and notional subordinated units, voting as separate classes. The ownership of more than 331/3% of the outstanding units by the Manager and its affiliates gives them the ability to prevent the Manager's removal. At March 31, 2015, Sponsor Holdings, which is an affiliate of the Manager, owned approximately 53.93% of the outstanding common and all of the notional subordinated units. At any time, the owners of the Manager may sell or transfer all or part of their ownership interests in the Manager to an affiliate or a third-party without the approval of the unitholders.
	Common units
	The common units are a class of non-managing membership interests in Niska Partners. The holders of the common units are entitled to participate in the Company's distributions and exercise the rights and privileges available to members under the Company's operating agreement. The operating agreement provides that the common unitholders have the right to receive distributions of Available Cash (as defined in the operating agreement) each quarter in an amount equal to $0.35 per common unit (the "Minimum Quarterly Distribution"), plus any arrearages in the payment of the Minimum Quarterly Distribution.
	Within 45 days after the end of each quarter Niska Partners may make cash distributions to the members of record on the applicable record date. Niska Partners distributed $39.7 million and $52.3 million to the holders of common units and the Managing Member during the years ended March 31, 2015 and 2014, respectively. On January 28 and May 6, 2015, the Company's Board of Directors suspended the quarterly distribution to common unitholders for the third and fourth quarters of fiscal 2015, respectively.
	Subordinated units
	All of the subordinated units were held by Sponsor Holdings.
	On April 2, 2013, the Company completed an equity restructuring which permanently eliminated Niska Partners' subordinated units and previous incentive distribution rights in return for the new IDRs. However, for a period of five years, and provided that the Carlyle/Riverstone Funds continue to own a majority of both the managing member and the new IDRs, the Carlyle/Riverstone Funds will be deemed to own 33.8 million "Notional Subordinated Units" in connection with votes to remove and replace the managing member. These Notional Subordinated Units are not entitled to distributions, but preserve the Carlyle/Riverstone Fund's voting rights with respect to the removal of the managing member.
	Unit-Based Performance Plan
	The Company maintains compensatory unit-based performance plans (the "Plans") to provide long-term incentive compensation for certain employees and directors, and to align their economic interest with those of common unitholders. The Plans are administered by the Compensation Committee of the Board of Directors and permit the grant of unit awards, restricted units, phantom units, unit options, unit appreciation rights, other unit-based awards, distribution equivalent rights and substitution awards. Unit-based awards are settled either in cash or in common units following the satisfaction of certain time and/or performance criteria.
	Unit-based awards are classified as liabilities when expected to be settled in cash or when the Company has the option to settle in cash or equity. This accounting treatment has resulted from the Company's historical practice of choosing to settle this type of award in cash. When awards are classified as liabilities, the fair value of the units granted is determined on the date of grant and is re-measured at each reporting period until the settlement date. The fair value at each re-measurement date is equal to the settlement expected to be incurred based on the anticipated number of units vested adjusted for (i) the passage of time and (ii) the payout threshold associated with the performance targets which the Company expects to achieve compared to its established peers. The performance criterion is based on total unitholder return ("TUR") metrics compared to such metrics of a select group of the Company's peers. The TUR metrics reflect the Company's percentile ranking during the applicable performance period compared to a peer group. The pro-rata number of units vested is calculated as the number of performance awards multiplied by the percentage of the requisite service period.
	Unit-based awards that are expected to be settled in units are classified as equity. The fair value of the units granted is determined on the date of grant and is amortized to equity using the straight-line method over the vesting period. Each equity settled award permits the holder to receive one common unit on the vesting date. The authorized number of common units that could be delivered under the Plans amounted to 3,380,474 units. As of March 31, 2015, there were 3,303,473 units (March 31, 2014—3,319,503 units) available for delivery. Of the total number available for delivery as of March 31, 2015, 808,081 units have been reserved for outstanding equity settled awards (nil as of March 31, 2014).
	All of the granted unit-based awards have the right to receive additional units in lieu of cash distributions paid on the outstanding units. The typical vesting period ranges from two to three years from the date of grant. Upon vesting, the units to be used to settle equity awards will come from the Company's authorized but unissued common units.
	The following tables summarize the Company's unit-based awards outstanding and nonvested unit-based awards as of March 31, 2015:

			Number of			Number of			Total Units
			Time-Based			Performance-
			Units			Based Units
	Unit-based awards outstanding—beginning of the year			835,360			487,200			1,322,560
	Granted			914,045			—			914,045
	Exercised			(501,883	)		(238,204	)		(740,087	)
	Forfeited			(161,597	)		(64,638	)		(226,235	)
	Distribution equivalent rights			113,416			30,321			143,737

	Unit-based awards outstanding—end of the year			1,199,341			214,679			1,414,020




			Number of			Number of			Total Units
Time-Based			Performance-
Units			Based Units
Non-vested unit-based awards—beginning of the year				466,858			312,764			779,622
Granted				914,045			—			914,045
Vested			(133,380	)		(63,769	)		(197,149	)
Forfeited			(159,737	)		(62,778	)		(222,515	)
Distribution equivalent rights			111,555			28,462			140,017

Non-vested unit-based awards—end of the year			1,199,341			214,679			1,414,020


As of March 31, 2015, outstanding unit-based awards classified as liability and equity amounted to 701,285 units and 712,735 units, respectively. Of the outstanding unit-based awards classified as liability, 95,347 units could be settled in cash or units.
Information on weighted average unit price at grant date and number of unit-based awards granted is as follows:

		Year ended March 31,
		2015			2014			2013
Weighted average price per unit at grant date		$	9.43		$	12.68		$	9.99
Number of unit-based awards granted			914,045			438,036			695,349
Unit-based compensation for the year ended March 31, 2015 was a recovery of $1.6 million and an expense of $11.2 million and $7.0 million for the years ended March 31, 2014 and 2013 respectively. Amounts paid to employees for unit-based awards settled in cash for the years ended March 31, 2015, 2014 and 2013 were $10.6 million, $2.3 million and $ nil, respectively. No equity awards were settled during the years ended March 31, 2015, 2014 and 2013.
As of March 31, 2015, there was $5.1 million (March 31, 2014—$5.9 million) of total unrecognized compensation cost related to nonvested unit-based awards granted that were subject to both time and performance conditions. That cost is expected to be recognized over the next three years.
Incentive distribution rights
IDRs are a separate interest and represent participating securities. The IDRs entitle the Carlyle/Riverstone Funds to receive 48% of any quarterly cash distributions after Niska Partners' common unitholders have received the full minimum quarterly distribution ($0.35 per unit) for each quarter plus any arrearages from prior quarters. To date, the Company has not made any payments with respect to the IDRs.
Earnings per unit
Niska Partners uses the two-class method for allocating earnings per unit ("EPU"). The two-class method requires the determination of net income allocated to member interests as shown below. Net earnings (loss) for the years ended March 31, 2015 and 2014, after the allocation to Managing Member's interest, was only attributable to common unitholders as a result of cancellation of the Company's subordinated units at the beginning of fiscal 2014. The cancellation of subordinated units did not impact the calculation of earnings per unit in fiscal 2013.

		Year ended March 31,
		2015			2014			2013
Numerator:
Net earnings (loss)		$	(350,656	)	$	(8,957	)	$	(43,601	)
Less:
Managing Member's interest			6,352			171			863

Net earnings (loss) attributable to common and subordinated unitholders		$	(344,304	)	$	(8,786	)	$	(42,738	)


Denominator:
Basic:
Weighted average units outstanding			36,882,713			34,941,036			68,296,990
Diluted:
Diluted:
Weighted average units outstanding			36,882,713			34,941,036			68,296,990
Earnings (loss) per unit allocated to common unitholders
—basic and diluted		$	(9.34	)	$	(0.25	)	$	(0.63	)


Earnings (loss) per unit allocated to subordinated unitholders
—basic and diluted		$	—		$	—		$	(0.63	)


The Company maintains a unit-based compensation plan that could dilute EPU in future periods. Because those awards were anti-dilutive for fiscal 2015, the EPU calculation above excludes a weighted average of 451,001 unit-based awards that will be settled as equity. Niska Partners did not have unit-based awards that could dilute future EPU during fiscal 2014 and fiscal 2013.

Revenues

Revenues	12 Months Ended
Revenues	Mar. 31, 2015
Revenues
Revenues	15. Revenues
	Niska Partners' fee-based revenue consists of the following:

		Year ended March 31,
		2015			2014			2013
	Long-term contract revenue	$	80,781		$	83,940		$	108,615
	Short-term contract revenue		11,559			51,416			54,710

		$	92,340		$	135,356		$	163,325


	Long-term contract revenue for the year ended March 31, 2015 included a one-time contract termination payment of $26.0 million as a result of the termination by TransCanada Gas Storage Partnership ("TransCanada"), the Company's largest volumetric customer, of its previous storage service agreement.
	Optimization, net consists of the following:

		Year ended March 31,
		2015			2014			2013
	Realized optimization, net	$	38,085		$	85,372		$	89,525
	Unrealized risk management gains (loss) (Notes 12 and 13)		31,694			(8,732	)		(89,874	)
	Write-downs of inventory		(63,800	)		(4,600	)		(22,281	)

		$	5,979		$	72,040		$	(22,630	)


	The Company's inventory is valued at the lower of weighted-average cost or market. During each of the year in the three-year period ended March 31, 2015, the forward prices of natural gas fell below the carrying cost of the Company's inventories, and as such, inventories were written down.

Depreciation_and_Amortization

Depreciation and Amortization	12 Months Ended
Depreciation and Amortization	Mar. 31, 2015
Depreciation and Amortization
Depreciation and Amortization	16. Depreciation and Amortization
	Depreciation and amortization consists of the following:

		Year ended March 31,
		2015		2014		2013
	Depreciation	$	93,190	$	30,636	$	38,901
	Amortization of intangible assets		23,633		10,543		11,311
	Accretion of asset retirement obligations		500		107		197

	Total	$	117,323	$	41,286	$	50,409


	Depreciation for the year ended March 31, 2015 includes $64.7 million (March 31, 2014—$nil; March 31, 2013—$9.3 million) related to migration of cushion at two of the Company's facilities. The Company records a provision for migration when it has been determined that cushion is no longer providing effective cushion support. Amortization of intangible assets for the year ended March 31, 2015 includes an amortization of $11.7 million related to the termination of the prior storage service agreement with TransCanada, to reflect the change in timing of cash flows related to this customer relationship.

Interest

Interest	12 Months Ended
Interest	Mar. 31, 2015
Interest
Interest	17. Interest
	The following table presents a reconciliation of interest expense:

		Year ended March 31,
		2015		2014		2013
	Gross interest	$	47,684	$	62,961	$	66,527
	Amortization of deferred financing costs		3,652		3,354		3,411
	Capitalized interest		—		—		(2,928	)

		$	51,336	$	66,315	$	67,010

Related_Party_Transactions

Related Party Transactions	12 Months Ended
Related Party Transactions	Mar. 31, 2015
Related Party Transactions
Related Party Transactions	18. Related Party Transactions
	The Company has recorded a receivable of $6.1 million from Holdco at March 31, 2015, as outlined in Note 19—Commitments and Contingencies. There were no amounts owing to or from related parties as at March 31, 2014.
	During the year ended March 31, 2015, Niska Partners recognized management fees amounting $ nil (March 31, 2014—$0.2 million; March 31, 2013—$0.2 million). Management fees are charged, on an arms-length basis, to affiliated entities for certain administrative services rendered and are recorded as a reduction to general and administrative costs.
	During the years ended March 31, 2015 and 2014, the Carlyle/Riverstone Funds elected to participate in the DRIP and were issued 2,243,470 common units (March 31, 2014—1,252,810 common units) in lieu of receiving cash distributions of $19.6 million (March 31, 2014—$18.3 million).

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Mar. 31, 2015
Commitments and Contingencies
Commitments and Contingencies	19. Commitments and Contingencies
	Contingencies
	As of March 31, 2015, the Company was under review by Canadian tax authorities for withholding taxes paid on behalf of Carlyle/Riverstone and the investors of the Carlyle/Riverstone Funds for earnings distributions made prior to the Company's IPO. The Company has received a notice from the Canadian tax authorities of a proposed assessment for $10.6 million and estimates the probable amount payable to range from $6.1 million to the proposed assessment of $10.6 million. The Company has recorded the minimum of the range, or $6.1 million, as a liability to the Canadian tax authorities. Niska Holdings L.P., a company held by the Carlyle/Riverstone Funds and the parent of Holdco, has guaranteed the repayment of any amounts owing with respect to this matter to the Company and has pledged its Common Units owned in the Company as collateral. Accordingly, as the Company believes collection of any amounts owing is reasonably assured, it has recorded a corresponding receivable of $6.1 million, thereby offsetting the impact of the contingent liability to the Company's results of operations and equity.
	The Company and its subsidiaries are also subject to other legal and tax proceedings and actions arising in the normal course of business. While the outcome of these proceedings and actions cannot be predicted with certainty, it is the opinion of Management that the resolution of such proceedings and actions will not have a material impact on the Company's consolidated financial position or results of operations.
	Commitments
	Niska Partners has entered into non-cancelable operating leases for office space, leases for land use rights at its operating facilities, storage capacity at other facilities, equipment, and vehicles used in its operations. The remaining lease terms expire between April 2015 and August 2056 and provide for the payment of taxes, insurance and maintenance by the lessee. A renewal option exists on the office space lease to extend the term for another five years, exercisable prior to the termination of the original lease.
	The related future minimum lease payments at March 31, 2015 were as follows:

	For the fiscal year ending:	Operating
	For the fiscal year ending:	leases
	2016	$	11,302
	2017		10,798
	2018		7,840
	2019		6,557
	2020		5,285
	2021 and thereafter		177,560

	Total minimum lease payments	$	219,342


	The minimum lease payments disclosed in the above table have not been reduced by the total of minimum rentals to be received in the future under non-cancelable subleases as of March 31, 2015 of $1.6 million. Consolidated lease and rental expense, net of sublease recoveries of $0.7 million, amounted to $13.6 million for the year ended March 31, 2015 (March 31, 2014—$11.9 million; March 31, 2013—$11.2 million). During the year ended March 31, 2015, lease and rental expense included contingent rent amounting to $ nil (March 31, 2014—$0.4 million; March 31, 2013—$0.3 million). Where applicable, contingent rent is due whenever a certain percentage of revenue exceeds minimum lease costs.
	Purchase obligations arising as a result of forward purchase contracts in place at March 31, 2015 were as follows:

	For the fiscal year ending:	Unconditional
		purchase
		obligations
	2016	$	981,883
	2017		192,618
	2018		299,210
	2019		8,579
	2020		2,519

	Total future purchase commitments	$	1,484,809


	Purchase obligations consisted of forward physical and financial commitments related to future purchases of natural gas. As the Company economically hedges substantially all of its natural gas purchases, there are forward sales that offset these commitments which are not included in the above table. As at March 31, 2015, forward physical and financial sales for all future periods totaled $1,485.3 million.
	As at March 31, 2015, the Company had $5.8 million of issued and outstanding letters of credit to various counterparties to support natural gas purchase commitments.
	As at March 31, 2015, one of the Company's Canadian subsidiaries owed certain interest payable to a non-Canadian affiliate. Niska Partners intends to file a tax election during fiscal 2016 that will deem this interest as paid. The election will trigger an obligation for the Company to pay withholding taxes of approximately $4.1 million to the Canadian tax authorities on behalf of the Company's unitholders. Consistent with similar transactions in the past, the Company will account for the payment as a distribution to unitholders, because unitholders can claim tax credits for the Canadian withholding taxes paid.

Changes_in_NonCash_Working_Cap

Changes in Non-Cash Working Capital	12 Months Ended
Changes in Non-Cash Working Capital	Mar. 31, 2015
Changes in Non-Cash Working Capital
Changes in Non-Cash Working Capital	20. Changes in Non-Cash Working Capital
	Changes in non-cash working capital include:

		Year ended March 31,
		2015			2014			2013
	Margin deposits	$	19,342		$	(14,137	)	$	(39,174	)
	Trade receivables		3,114			(3,383	)		(286	)
	Accrued receivables		110,484			(44,459	)		(40,203	)
	Natural gas inventory		(124,955	)		3,676			125,042
	Prepaid expenses and other current assets		542			358			(1,527	)
	Other assets		(517	)		(807	)		(1,105	)
	Trade payables		(212	)		(149	)		645
	Accrued liabilities		(63,709	)		68,106			8,927
	Deferred revenue		596			5,468			(10,667	)
	Other long-term liabilities		(520	)		360			381

	Net changes in non-cash working capital	$	(55,835	)	$	15,033		$	42,033


	During the year ended March 31, 2013, changes in non-cash working capital include the receipt of proceeds of $32.6 million (March 31, 2015—$ nil; March 31, 2014—$ nil) from sales of cushion. The Company included such proceeds in cash flows from operations since the predominant source of cash flows for natural gas purchases and sales are operating in nature.

Supplemental_Cash_Flow_Disclos

Supplemental Cash Flow Disclosures	12 Months Ended
Supplemental Cash Flow Disclosures	Mar. 31, 2015
Supplemental Cash Flow Disclosures
Supplemental Cash Flow Disclosures	21. Supplemental Cash Flow Disclosures

		Year ended March 31,
		2015		2014			2013
	Interest paid	$	30,083	$	63,769		$	67,408
	Taxes paid (received)		50		73			(722	)
	Interest capitalized		—		—			2,928
	Non-cash investing activities:
	Non-cash investing activities:
	Non-cash increase (decrease) in working capital related to property, plant and equipment	$	2,203	$	(2,426	)	$	(8,605	)
	Non-cash transfer of natural gas inventory to cushion		—		15,264			—
	Non-cash financing activities:
	Non-cash distributions and reinvestments		19,631		18,270			—
	In March 2014, the Company reclassified the balance of its long-term natural gas inventory to cushion within property, plant and equipment to reflect operational requirements.

Segment_Disclosures

Segment Disclosures	12 Months Ended
Segment Disclosures	Mar. 31, 2015
Segment Disclosures
Segment Disclosures	22. Segment Disclosures
	The Company's process for the identification of reportable segments involves examining the nature of services offered, the types of customer contracts entered into and the nature of the economic and regulatory environment.
	Niska Partners operates along functional lines in its commercial, engineering, and operations teams for operations in Alberta, Northern California, and the U.S. Midcontinent. All functional lines and facilities offer the same services: fee-based revenue, and optimization. The Company has a marketing business which is an extension of the Company's proprietary optimization activities. Proprietary optimization activities occur when the Company purchases, stores and sells natural gas for its own account in order to utilize or optimize storage capacity that is not contracted or available to third party customers. All services are delivered using reservoir storage. The Company measures profitability consistently along all functional lines based on revenues and earnings before interest, taxes, depreciation and amortization, before unrealized risk management gains and losses. The Company has aggregated its operating segments into one reportable segment as at March 31, 2015 and 2014 and for each of the three years ended March 31, 2015.
	Information pertaining to the Company's short term and long term contract services and net optimization revenues is presented on the consolidated statements of earnings (loss) and comprehensive income (loss). All facilities have the same types of customers: major companies in the energy industry, industrial, commercial, and local distribution companies, and municipal energy consumers. Revenues are primarily attributed to the geographic area based on where services are provided or the natural gas is sold.
	The following tables summarize the net revenues and long-lived assets by geographic area:

		Year ended March 31,
		2015			2014			2013
	Net realized revenues
	U.S.	$	32,265		$	58,128		$	73,905
	Canada		98,160			162,600			178,945
	Net unrealized revenues
	U.S.		20,452			142			(37,139	)
	Canada		11,242			(8,874	)		(52,735	)
	Write-downs of inventory
	U.S.		(22,600	)		(500	)		(3,744	)
	Canada		(41,200	)		(4,100	)		(18,537	)
	Inter-entity
	U.S.		(4,266	)		—			—
	Canada		4,266			—			—

		$	98,319		$	207,396		$	140,695




		As at March 31,
		2015			2014
	Long-lived assets
	U.S.	$	367,920		$	397,331
	Canada		508,706			839,917

		$	876,626		$	1,237,248

Economic_Dependence

Economic Dependence	12 Months Ended
Economic Dependence	Mar. 31, 2015
Economic Dependence
Economic Dependence	23. Economic Dependence
	Niska Partners' exposure to the volume of business transacted with a natural gas clearing and settlement facility is described in Note 12. While the clearing and settlement facility is its direct counterparty, its risk exposure to dependence on this counterparty is mitigated through the large number of members of the clearing and settlement facility who create the demand for these transactions.
	During the three years ended March 31, 2015, Niska Partners did not have any other customers comprise greater than 10% of total gross revenue.

Quarterly_Financial_Data

Quarterly Financial Data	12 Months Ended
Quarterly Financial Data	Mar. 31, 2015
Quarterly Financial Data
Quarterly Financial Data	24. Quarterly Financial Data
	Quarterly results are influenced by the seasonal and other factors inherent in Niska Partners' business. The following table summarizes the quarterly financial data for the years ended March 31, 2015 and 2014:

		First			Second			Third			Fourth			Year ended
		Quarter			Quarter			Quarter			Quarter			March 31,
		(unaudited)			(unaudited)			(unaudited)			(unaudited)
	Fiscal 2015
	Revenue, net	$	55,377		$	10,590		$	39,219		$	(6,867	)	$	98,319
	Earnings (loss) before income taxes		(27,864	)		(36,180	)		(275,258	)		(43,010	)		(382,312	)
	Net earnings (loss) and comprehensive income (loss)		(18,972	)		(28,832	)		(259,623	)		(43,229	)		(350,656	)
	Earnings (loss) per unit		(0.52	)		(0.78	)		(6.85	)		(1.12	)		(9.34	)
	Fiscal 2014
	Fiscal 2014
	Revenue, net	$	57,189		$	36,863		$	25,847		$	87,497		$	207,396
	Earnings (loss) before income taxes		7,667			(7,797	)		(19,718	)		635			(19,213	)
	Net earnings (loss) and comprehensive income (loss)		7,967			(7,845	)		(13,409	)		4,330			(8,957	)
	Earnings (loss) per unit		0.23			(0.22	)		(0.37	)		0.12			(0.25	)
	During the first quarter of fiscal 2015, net revenue included a one-time contract termination payment of $26.0 million. The Company also recorded a provision of $27.9 million related to the migration of cushion during the same period. In the second quarter of fiscal 2015, the Company wrote down proprietary inventories by $10.5 million and recorded a provision of $5.7 million related to cushion migration. During the third quarter of fiscal 2015, the Company recorded a goodwill impairment of $245.6 million, wrote down proprietary inventories by $31.7 million and recorded a provision of $31.1 million related to cushion migration. During the fourth quarter of fiscal 2015, the Company wrote down proprietary inventories by $21.6 million. The Company recognized a loss on extinguishment of debt of $36.7 million and wrote down proprietary inventories by $4.6 million in the fourth quarter of fiscal 2014.

Significant_Accounting_Policie1

Significant Accounting Policies (Policies)	12 Months Ended
	Mar. 31, 2015
Significant Accounting Policies
Basis of presentation	Basis of presentation
	These consolidated financial statements have been prepared to reflect the consolidated financial position, results of operations and cash flows of Niska Partners and its subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP").
	These financial statements include the accounts of Niska Partners and its wholly-owned subsidiaries, including AECO Gas Storage Partnership, Wild Goose Storage LLC, Niska Gas Storage, LLC, Salt Plains Storage, LLC, Access Gas Services Inc., Access Gas Services (Ontario) Inc., EnerStream Agency Services Inc., and Niska Partners Management ULC. All material intercompany transactions have been eliminated, as well as various management and holding companies.

Use of estimates	Use of estimates
	In preparing these financial statements, Niska Partners is required to make estimates and assumptions that affect both the amount and timing of recording assets, liabilities, revenues and expenses since the determination of these items may be dependent on future events. Management uses the most current information available and exercises careful judgment in making these estimates. Although management believes that these consolidated financial statements have been prepared within the limits of materiality and within the framework of its significant accounting policies summarized below, actual results could differ from these estimates. Changes in estimates are accounted for on a prospective basis.

Revenue recognition	Revenue recognition
	The Company's assessment of each of the four revenue recognition criteria as they relate to its revenue producing activities is as follows:
	Persuasive evidence of an arrangement exists. The Company's customary practices are to enter into a written contract, executed by both the customer and the Company.
	Delivery. Delivery is deemed to have occurred at the time the natural gas is delivered and title is transferred, or in the case of fee-based arrangements, when the services are rendered. To the extent the Company retains its inventory, delivery occurs when the inventory is subsequently sold and title is transferred to the third-party purchaser.
	The fee is fixed or determinable. The Company negotiates the fee for its services at the outset of their fee-based arrangements. In these arrangements, the fees are nonrefundable. The fees are generally due on the 25th of the month following the delivery or services rendered. For other arrangements, the amount of revenue is determinable when the sale of the applicable product has been completed upon delivery and transfer of title.
	Collectability is reasonably assured. Collectability is evaluated on a customer-by-customer basis. New and existing customers are subject to a credit review process, which evaluates the customers' financial position (e.g. cash position and credit rating) and their ability to pay. If collectability is not considered reasonably assured at the outset of an arrangement in accordance with the Company's credit review process, revenue is recognized when the fee is collected.
	Fee-based revenue consists of long-term contracts for storage fees that are generated when we lease storage capacity on a monthly basis and short-term fees associated with park and loan activities. Long-term contract revenue consists of monthly storage fees and fuel and commodity charges for injections and withdrawals. Long-term contract revenue is accrued on a monthly basis in accordance with the terms of the customer contracts. Customer charges for injections and withdrawals are recorded in the month of injection or withdrawal. Short-term contract revenue consists of fees for injections and withdrawals, where the customer pays a fixed fee to inject a specified quantity of natural gas on a specified date or dates and withdraw a specified quantity of natural gas on a specified date. The fee stipulated in a short-term contract for each performance obligation (injection and withdrawal) is recognized when the service occurs.
	Energy trading contracts resulting in the delivery of a commodity where Niska Partners is the principal in the transaction are recorded as optimization revenues at the time of physical delivery. Realized and unrealized gains and losses on financial energy trading contracts are included in optimization revenue (see Note 12).
	Optimization revenue, net includes realized gains and losses and the net change in unrealized gains and losses on financial and physical energy trading contracts. Optimization revenue results from the purchase of inventory and its forward sale to future periods through financial and physical trading contracts. These derivative contracts are economic hedges that have been entered into to manage commodity price and currency risk associated with buying and selling natural gas across future time periods (see Note 12). The Company does not designate these instruments as hedges and therefore records the unrealized gains and losses on the changes in their fair value through net earnings. Contracts resulting in the delivery of a commodity where Niska Partners is the principal in the transaction are recorded as optimization revenues at the time of physical delivery.
	Sales taxes collected from customers and remitted to governmental authorities are excluded from revenues in the consolidated statements of earnings (loss) and comprehensive income (loss).

Cash and cash equivalents	Cash and cash equivalents
	Niska Partners considers all highly liquid investments purchased with an initial maturity of three months or less to be cash equivalents.

Margin deposits	Margin deposits
	Cash held in margin represents the right to receive or the obligation to pay cash collateral under a master netting arrangement that has not been offset against derivative positions. These derivatives are marked-to-market daily; the profit or loss on the daily position is then paid to, or received from, the account as appropriate under the terms of the Company's contract with its broker.

Natural gas inventory	Natural gas inventory
	The Company's inventory is natural gas injected into storage which is held for resale. Inventory is valued at the lower of weighted average cost or market. Adjustments to write down the costs of inventory to market are recorded as an offset to optimization revenues while costs to store the gas are recognized as operating expenses in the period the costs are incurred in the consolidated statements of earnings (loss) and comprehensive income (loss).

Property, plant and equipment	Property, plant and equipment
	Property, plant and equipment are recorded at cost when purchased. Depreciation is computed using the declining balance method for each category of asset using the following rates:

	Pipelines and measurement	5%
	Wells	5%
	Facilities (excluding costs of major overhauls)	Between 5% and 22%
	Computer hardware and software	30%
	Office furniture and fixtures	20%
	Other	10%
	Property, plant and equipment under capital leases are depreciated using the declining balance method over the lesser of the useful lives of the assets or the lease term.
	Costs of major overhauls of engines and compressors included within the facilities account are depreciated using the actual number of hours used over the estimated number of hours until the next scheduled major overhaul.
	Certain volumes of hydrocarbons defined as cushion are required for maintaining a minimum field pressure. Cushion is considered a component of the facility and as such is not amortized. Cushion is monitored to ensure that it provides effective pressure support for the facility. In the event that cushion moves to another area of the reservoir where it does not provide effective pressure support, a loss is recorded, within depreciation expense, equal to the estimated volumes that have migrated. Proceeds from sale of cushion are classified as operating activities in the consolidated statements of cash flows since the predominant source of cash flows for natural gas purchases and sales are operating in nature.
	Repairs, maintenance and renewals that do not provide future economic benefits to the assets are expensed as incurred. Interest costs for the construction or development of long-lived assets held by operational entities are capitalized and amortized over the related asset's estimated useful life.

Asset retirement obligations	Asset retirement obligations
	Niska Partners records a liability for an asset retirement obligation when the legal obligation to retire the asset has been incurred with an offsetting increase to the carrying value of the related tangible long-lived asset. The recognition of an asset retirement obligation requires that management make numerous estimates, assumptions and judgments regarding such factors as the estimated probabilities, amounts and timing of settlements, the credit-adjusted risk-free rate, inflation rates and future advances in technology. In periods subsequent to initial measurement of the liability, the Company must recognize changes in the liability resulting from the passage of time and revisions to either the timing or the amount of the original estimate of undiscounted cash flows. Over time, the liability is accreted to its future value, and the capitalized cost is depreciated over the useful life of the related asset. Accretion of the asset retirement obligations due to the passage of time is recorded as an expense in the statement of earnings. Upon settlement of the liability, the Company either settles the obligation for its recorded amount or incurs a gain or loss.

Netting of certain balance sheet accounts	Netting of certain balance sheet accounts
	Certain risk management assets and liabilities and certain accrued gas sales and purchases are presented on a net basis in the balance sheet when all of the following exist: (i) Niska Partners and the other party owe the other a determinable amount; (ii) the Company has the right to set off the amount owed with the amount owed by the other party; (iii) Niska Partners intends to set off; and (iv) the right of setoff is enforceable by law.

Leases	Leases
	Niska Partners determines a lease to be an operating or capital lease based upon the terms of the lease, estimated fair value of the leased assets, estimated life of the leased assets, and the contractual minimum lease payments as defined within the lease agreements. If the Company concludes that it has substantively all of the risks of ownership of a leased property and therefore is deemed the owner of the property for accounting purposes, it records an asset and related obligations under capital lease at the lower of the present value of the minimum lease payments or the fair value of the asset.

Impairment of long-lived assets	Impairment of long-lived assets
	Niska Partners evaluates whether events or circumstances have occurred that indicate that long-lived assets may not be recoverable or that the remaining useful life may warrant revision. When such events or circumstances are present, the Company assesses the recoverability of long-lived assets by determining whether the carrying value will be recovered through the expected undiscounted future cash flows. In the event that the sum of the expected future cash flows resulting from the use of the asset is less than the carrying value of the asset, an impairment loss equal to the excess of the asset's carrying value over its fair value is recorded.

Goodwill and other intangible assets	Goodwill and other intangible assets
	Niska Partners accounts for business acquisitions using the purchase method of accounting and, accordingly, the assets and liabilities of the acquired entities are recorded at their estimated fair values at the date of acquisition. The excess of the purchase price over the fair value of the net assets acquired is attributed to goodwill.
	Goodwill is not amortized and is re-evaluated on an annual basis or more frequently if events or changes in circumstances indicate that the asset might be impaired. Goodwill is tested for impairment between annual tests if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value. These events or circumstances could include a significant change in the business climate, legal factors, operating performance indicators, competition, sale or disposition of a significant portion of the business or other factors.
	To re-evaluate goodwill for impairment, the Company has the option to first assess qualitative factors to determine whether it is more likely than not that goodwill is impaired. The result of the qualitative assessment would be used as a basis in determining whether it is necessary to perform the quantitative impairment test. The performance of the quantitative impairment test involves a two-step process. The first step involves comparing the fair values of the applicable reporting units with their aggregate carrying values, including goodwill. If the carrying amount exceeds the fair value of the reporting unit, the Company performs the second step of the goodwill impairment test to determine the amount of impairment loss. The second step of the goodwill impairment test involves comparing the implied fair value of the affected reporting unit's goodwill with the carrying value of that goodwill.
	Other intangible assets represent contractual rights obtained in connection with a business combination that had favorable contractual terms relative to market as of the acquisition date.
	Intangible assets representing customer contracts and relationships are amortized over their useful lives. These assets are reviewed for impairment as impairment indicators arise. When such events or circumstances are present, the recoverability of long-lived assets is assessed by determining whether the carrying value will be recovered through the expected undiscounted future cash flows. In the event that the sum of the expected future cash flows resulting from the use of the asset is less than the carrying value of the asset, an impairment loss equal to the excess of the asset's carrying value over its fair value is recorded.
	Pipeline rights of way are formal agreements granting rights of way in perpetuity and are not subject to amortization but are subject to an annual impairment test.

Risk management activities	Risk management activities
	The Company uses natural gas derivatives and other financial instruments to manage its exposure to changes in natural gas prices, and foreign exchange rates. These financial assets and liabilities, which are recorded at fair value on a recurring basis, are included in one of three categories based on a fair value hierarchy with realized and unrealized gains (losses) recognized in net earnings (loss) for the period (see Note 13).
	The fair value of the Company's derivative risk management contracts are recorded as a component of risk management assets and liabilities, which are classified as current or non-current assets or liabilities based upon the anticipated settlement date of the contracts.

Foreign currency translation	Foreign currency translation
	The functional and reporting currency of the Company is the U.S. dollar. Non-U.S. dollar denominated monetary items are translated into U.S. dollars at the rate of exchange in effect at the balance sheet date. Non-U.S. dollar denominated non-monetary items are translated to U.S. dollars at the exchange rate in effect when the transaction occurred. Revenues and expenses denominated in foreign currencies are translated at the actual exchange rate or average exchange rate in effect during the period. Foreign exchange gains or losses on translation are included as a component of net earnings (loss) for the period.

Deferred financing costs	Deferred financing costs
	Deferred financing costs relate to costs incurred on the issuance of debt, and are amortized over the term of the related debt to interest expense using the effective interest method for costs related to the senior notes offering. Deferred financing costs incurred on the revolving credit facilities are amortized on a straight line basis. Any remaining unamortized deferred financing costs related to repurchased senior notes or modified revolving credit facility agreements are written off on the dates of redemption or modification.

Income taxes	Income taxes
	The Company is not a directly taxable entity. Income taxes on its income are the responsibility of the individual unitholders and accordingly, have not been recorded in the consolidated financial statements. However, Niska Partners does own corporate subsidiaries which are taxable corporations subject to Canadian federal and provincial income taxes and which are included in the consolidated financial statements.
	Income taxes on the Canadian corporate subsidiaries are determined using the asset and liability method, which results in deferred income tax assets and liabilities arising from temporary differences. Temporary differences are differences between the tax basis of assets and liabilities and their reported amounts in the financial statements that will result in taxable or deductible amounts in future years. This method requires the effect of tax rate changes on current and accumulated deferred income taxes to be reflected in the period in which the rate change was enacted. The asset and liability method also requires that deferred income tax assets be reduced by a valuation allowance unless it is more likely than not that the assets will be realized.
	The Company's policy is to recognize accrued interest and penalties on accrued tax balances as components of interest expense.

Unit-based performance plan	Unit-based performance plan
	Niska Partners' compensation committee approves the awards of unit-based performance plans to certain key employees. These awards include both time and performance-based components.
	Unit-based awards are classified as liabilities when expected to be settled in cash or when the Company has the option to settle in cash or equity. This accounting treatment has resulted from the Company's historical practice of choosing to settle this type of award in cash. When awards are classified as liabilities, the fair value of the units granted is determined on the date of grant and is re-measured at each reporting period until the settlement date. The fair value at each re-measurement date is equal to the settlement expected to be incurred based on the anticipated number of units vested, adjusted for (i) the passage of time and (ii) the payout threshold associated with the performance targets which the Company expects to achieve compared to its established peers. The pro-rata number of units vested is calculated as the number of performance awards multiplied by the percentage of the requisite service period.
	Unit-based awards that are expected to be settled in units are classified as equity. The fair value of the units granted is determined on the date of grant and is amortized to equity using the straight-line method over the vesting period. Each equity settled award permits the holder to receive one common unit on the vesting date.
	All of the granted unit-based awards have the right to receive additional units in lieu of cash distributions paid on the outstanding units. The typical vesting period ranges from two to three years from the date of grant.

Significant_Accounting_Policie2

Significant Accounting Policies (Tables)	12 Months Ended
Significant Accounting Policies (Tables)	Mar. 31, 2015
Significant Accounting Policies
Schedule of rates used in computation of depreciation using the declining balance method for each category of asset
	Pipelines and measurement	5%
	Wells	5%
	Facilities (excluding costs of major overhauls)	Between 5% and 22%
	Computer hardware and software	30%
	Office furniture and fixtures	20%
	Other	10%

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	12 Months Ended
Property, Plant and Equipment (Tables)	Mar. 31, 2015
Property, Plant and Equipment
Schedule of components of property, plant and equipment

		As at March 31, 2015
		Cost		Accumulated			Net Book
		Cost		Depreciation			Value
	Cushion	$	356,655	$	—		$	356,655
	Pipelines and measurement		296,669		(102,885	)		193,784
	Wells		127,297		(45,004	)		82,293
	Facilities		276,892		(92,473	)		184,419
	Computer hardware and software		4,293		(3,440	)		853
	Construction in progress, including projects under development		1,486		—			1,486
	Office furniture, equipment and other		2,515		(1,538	)		977

		$	1,065,807	$	(245,340	)	$	820,467




		As at March 31, 2014
		Cost		Accumulated			Net Book
		Cost		Depreciation			Value
	Cushion	$	421,404	$	—		$	421,404
	Pipelines and measurement		296,671		(92,687	)		203,984
	Wells		126,694		(40,700	)		85,994
	Facilities		272,645		(79,028	)		193,617
	Computer hardware and software		4,225		(3,087	)		1,138
	Construction in progress, including projects under development		1,063		—			1,063
	Office furniture, equipment and other		2,473		(1,399	)		1,074

		$	1,125,175	$	(216,901	)	$	908,274

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
Goodwill and Other Intangible Assets (Tables)	Mar. 31, 2015
Goodwill and Other Intangible Assets
Schedule of allocation of goodwill balances and related impairment charges by reporting unit

		AECO			NGPL			Total
		HubTM			Leased
					Capacity
	Balance, April 1, 2014	$	228,004		$	17,600		$	245,604
	Impairment charges		(228,004	)		(17,600	)		(245,604	)

	Balance, March 31, 2015	$	—		$	—		$	—




Schedule of other intangible assets

		As at March 31,
		2015			2014
	Customer contracts and relationships, beginning of the year	$	165,080		$	163,073
	Additions		—			2,007
	Less accumulated amortization		(141,521	)		(117,888	)

	Customer contracts and relationships, end of the year		23,559			47,192
	Pipeline rights of way		18,270			18,270

		$	41,829		$	65,462




Schedule of estimated future amortization expense

	For the fiscal year ending:	Amortization
	For the fiscal year ending:	Expense
	March 31, 2016	$	5,977
	March 31, 2017		7,513
	March 31, 2018		3,558
	March 31, 2019		3,341
	March 31, 2020 and thereafter		3,170

Deferred_Financing_Costs_Table

Deferred Financing Costs (Tables)	12 Months Ended
Deferred Financing Costs (Tables)	Mar. 31, 2015
Deferred Financing Costs
Schedule of deferred financing costs

		As at March 31,
		2015			2014
	Deferred financing costs, beginning of the year	$	20,078		$	25,377
	Additions		13			11,696
	Write-off due to extinguishment of debt		—			(16,995	)

	Deferred financing costs, end of the year		20,091			20,078

	Accumulated amortization, beginning of the year		(5,438			(10,957
	Accumulated amortization, beginning of the year		(5,438	)		(10,957	)
	Amortization recognized as interest (see Note 17)		(3,652	)		(3,354	)
	Write-off due to extinguishment of debt		—			8,873

	Accumulated amortization, end of the year		(9,090	)		(5,438	)

	Net book value	$	11,001		$	14,640


	Life in years		2 - 4			3 - 5

Debt_Tables

Debt (Tables)	12 Months Ended
Debt (Tables)	Mar. 31, 2015
Debt
Schedule of debt obligations

		As at March 31,
		2015			2014
	6.50% Senior Notes due 2019	$	575,000		$	575,000
	Revolving credit facilities		193,500			119,500

			768,500			694,500
	Less: portion classified as current		(193,500	)		(119,500	)

		$	575,000		$	575,000

Obligations_Under_Capital_Leas1

Obligations Under Capital Lease (Tables)	12 Months Ended
Obligations Under Capital Lease (Tables)	Mar. 31, 2015
Obligations Under Capital Lease
Schedule of future principal and interest payments of obligations under capital lease

	For the fiscal year ending:
	March 31, 2016	$	1,657
	March 31, 2017		1,657
	March 31, 2018		1,657
	March 31, 2019		1,657
	March 31, 2020		1,657
	March 31, 2021 and thereafter		3,917
	Less: Amount representing interest		(1,276	)

		$	10,926

Accrued_Liabilities_Tables

Accrued Liabilities (Tables)	12 Months Ended
Accrued Liabilities (Tables)	Mar. 31, 2015
Accrued Liabilities
Schedule of accrued liabilities

		As at March 31,
		2015		2014
	Accrued interest	$	21,411	$	2,037
	Accrued gas purchases		13,917		75,454
	Employee-related accruals		2,369		22,315
	Other accrued liabilities		9,989		11,312

		$	47,686	$	111,118

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	12 Months Ended
Asset Retirement Obligations (Tables)	Mar. 31, 2015
Asset Retirement Obligations
Schedule of asset retirement obligations

		As at March 31,
		2015			2014
	Balance, beginning of the year	$	1,975		$	2,007
	Additions		22			—
	Accretion		500			107
	Effect of foreign exchange translation		(189	)		(139	)

	Balance, end of the year	$	2,308		$	1,975

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Mar. 31, 2015
Income Taxes
Schedule of components of the Company's earnings (loss) before income taxes

		Year ended March 31,
		2015			2014			2013
	Domestic	$	6,506		$	16,844		$	(493	)
	Foreign		(388,818	)		(36,057	)		(62,050	)

		$	(382,312	)	$	(19,213	)	$	(62,543	)




Schedule of total income tax expense (benefit) differed from the amounts computed by applying the tax rate to earnings (loss) before income taxes

		Year ended March 31,
		2015			2014			2013
	Earnings (loss) before taxes	$	(382,312	)	$	(19,213	)	$	(62,543	)
	U.S. federal corporate statutory rate		35	%		35	%		35	%

	Expected tax benefits		(133,809	)		(6,725	)		(21,890	)
	Non-deductible expense related to asset impairment		57,001
	Non-deductible expense related to asset impairment		57,001			—			—
	Canadian statutory tax rate differences		39,056			3,559			6,145
	Adjustments and assessments		2,592			(690	)		(4,796	)
	Change in valuation allowance		2,314			(1,248	)		(452	)
	Earnings (loss) of non-taxable entities		(1,925	)		(6,296	)		1,377
	Non-deductible expenses and other		3,115			1,144			674

	Income tax benefit	$	(31,656	)	$	(10,256	)	$	(18,942	)




Schedule of significant components of the deferred income tax liabilities and deferred income tax assets

		As at March 31,
		2015			2014
	Deferred income tax assets:
	Non-capital loss carry forwards	$	18,959		$	18,434
	Risk management liabilities		19,919			33,386
	Capital losses		4,223			2,358
	Deferred financing costs		4,006			6,890
	Other		2,774			2,403

			49,881			63,471
	Valuation allowance		(7,173	)		(4,004	)

	Total deferred income tax assets	$	42,708		$	59,467


	Deferred income tax liabilities:
	Property, plant and equipment	$	99,628		$	114,298
	Risk management assets		24,202			17,049
	Intangible assets		9,510			15,137
	Partnership deferral income		—			37,499
	Other		19			535

	Total deferred income tax liabilities		133,359			184,518

	Net deferred income tax liabilities	$	90,651		$	125,051




Schedule of classification of net deferred income tax liabilities

		As at March 31,
		2015			2014
	Deferred income tax liabilities:
	Current	$	2,334		$	5,678
	Long-term		88,317			119,373

		$	90,651		$	125,051




Schedule of changes in unrecognized tax benefits

		As at March 31,
		2015			2014
	Balance at beginning of the year	$	1,735		$	1,160
	Additions based on tax positions taken in the current year		—			375
	(Reductions) additions based on tax positions taken in a prior year		(205	)		200

	Balance at end of the year	$	1,530		$	1,735

Risk_Management_Activities_and1

Risk Management Activities and Financial Instruments (Tables)	12 Months Ended
	Mar. 31, 2015
Risk Management Activities and Financial Instruments
Schedule of volumes of inventories which were economically hedged using each type of contract

		As at March 31,
		2015	2014
	Forwards	1.5 Bcf	(1.4 Bcf)
	Futures	46.0 Bcf	20.1 Bcf
	Swaps	(0.3 Bcf)	(0.3 Bcf)

		47.2 Bcf	18.4 Bcf

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
Fair Value Measurements (Tables)	Mar. 31, 2015
Fair Value Measurements
Schedule of fair values of risk management assets and liabilities

	As at March 31, 2015	Energy			Currency			Total
	As at March 31, 2015	Contracts			Contracts			Total
	Short-term risk management assets	$	39,392		$	2,208		$	41,600
	Long-term risk management assets		29,647			1,281			30,928
	Short-term risk management liabilities		(25,560	)		—			(25,560	)
	Long-term risk management liabilities		(20,512	)		(321	)		(20,833	)

		$	22,967		$	3,168		$	26,135




	As at March 31, 2014	Energy			Currency			Total
	As at March 31, 2014	Contracts			Contracts			Total
	Short-term risk management assets	$	18,939		$	2,010		$	20,949
	Long-term risk management assets		4,260			546			4,806
	Short-term risk management liabilities		(18,945	)		(160	)		(19,105	)
	Long-term risk management liabilities		(12,209	)		—			(12,209	)

		$	(7,955	)	$	2,396		$	(5,559	)




Schedule of risk management assets and liabilities that had netting or rights of offset arrangements

	As at March 31, 2015	Gross Amounts			Gross Amounts			Net Amounts			Margin			Net
		Recognized			Offset in the			Presented in			Deposits not			Amounts
					Balance Sheet			the Balance			Offset in the
								Sheet			Balance Sheet
	Assets
	Commodity derivatives	$	148,385		$	(79,346	)	$	69,039		$	(50,070	)	$	18,969
	Currency derivatives		5,167			(1,678	)		3,489			—			3,489

	Total assets		153,552			(81,024	)		72,528			(50,070	)		22,458

	Liabilities
	Commodity derivatives		125,418			(79,346	)		46,072			(39,338	)		6,734
	Currency derivatives		1,999			(1,678	)		321			(321	)		—

	Total liabilities		127,417			(81,024	)		46,393			(39,659	)		6,734

	Net	$	26,135		$	—		$	26,135		$	(10,411	)	$	15,724




	As at March 31, 2014	Gross Amounts			Gross Amounts			Net Amounts			Margin			Net
		Recognized			Offset in the			Presented in			Deposits not			Amounts
					Balance Sheet			the Balance			Offset in the
								Sheet			Balance Sheet
	Assets
	Commodity derivatives	$	113,175		$	(89,976	)	$	23,199		$	(15,101	)	$	8,098
	Currency derivatives		2,851			(295	)		2,556			(2,556	)		—

	Total assets		116,026			(90,271	)		25,755			(17,657	)		8,098

	Liabilities
	Commodity derivatives		121,130			(89,976	)		31,154			(21,705	)		9,449
	Currency derivatives		455			(295	)		160			(160	)		—

	Total liabilities		121,585			(90,271	)		31,314			(21,865	)		9,449

	Net	$	(5,559	)	$	—		$	(5,559	)	$	4,208		$	(1,351	)




Schedule of risk management assets and liabilities outstanding expected to be realized into net earnings and comprehensive income in the fiscal periods

	Fiscal year ending March 31,	Energy			Currency			Total
	Fiscal year ending March 31,	Contracts			Contracts			Total
	2016	$	13,832		$	2,208		$	16,040
	2017 and beyond		9,135			960			10,095

		$	22,967		$	3,168		$	26,135




Summary of net realized and unrealized optimization gains and losses from the settlement of risk management contracts


		Year ended March 31,
		2015			2014			2013			Classification
	Energy contracts
	Realized	$	40,787		$	(78,778	)	$	41,304		Optimization, net
	Unrealized		30,922			(10,662	)		(90,641	)	Optimization, net
	Currency contracts
	Realized		2,459			3,177			1,377		Optimization, net
	Unrealized		772			1,930			790		Optimization, net

		$	74,940		$	(84,333	)	$	(47,170	)




Schedule of assets and liabilities that were accounted for or disclosed at fair value on a recurring and non-recurring basis

	As at March 31, 2015	Level 1			Level 2			Level 3			Total
	Assets
	Commodity derivatives	$	—		$	69,039		$	—		$	69,039
	Currency derivatives		—			3,489			—			3,489
	Goodwill		—			—			—			—

	Total assets	$	—		$	72,528		$	—		$	72,528


	Liabilities
	Commodity derivatives	$	—		$	46,072		$	—		$	46,072
	Currency derivatives		—			321			—			321
	Long-term debt		—			432,688			—			432,688

	Total liabilities	$	—		$	479,081		$	—		$	479,081




	As at March 31, 2014	Level 1			Level 2			Level 3			Total
	Assets
	Commodity derivatives	$	—		$	23,199		$	—		$	23,199
	Currency derivatives		—			2,556			—			2,556

	Total assets	$	—		$	25,755		$	—		$	25,755


	Liabilities
	Commodity derivatives	$	—		$	31,154		$	—		$	31,154
	Currency derivatives		—			160			—			160
	Long-term debt		—			570,700			—			570,700

	Total liabilities	$	—		$	602,014		$	—		$	602,014

Members_Equity_Tables

Members' Equity (Tables)	12 Months Ended
Members' Equity (Tables)	Mar. 31, 2015
Members' Equity
Schedule of reconciliation of units outstanding

		Common			Subordinated			Total
		Unitholders			Unitholders			Total
	Units outstanding at March 31, 2012 and 2013		34,492,245			33,804,745			68,296,990
	Subordinated units cancelled April 2, 2013		—			(33,804,745	)		(33,804,745	)
	Units issued under the DRIP		1,252,815			—			1,252,815

	Units outstanding at March 31, 2014		35,745,060			—			35,745,060
	Units issued under the DRIP		2,243,664			—			2,243,664

	Units outstanding at March 31, 2015		37,988,724			—			37,988,724




Unit-based compensation
Schedule of weighted average unit price at grant date and number of unit-based awards granted

		Year ended March 31,
		2015			2014			2013
	Weighted average price per unit at grant date	$	9.43		$	12.68		$	9.99
	Number of unit-based awards granted		914,045			438,036			695,349


Earnings per share
Schedule of net earnings (loss) allocation and net earnings (loss) per unit calculation

		Year ended March 31,
		2015			2014			2013
	Numerator:
	Net earnings (loss)	$	(350,656	)	$	(8,957	)	$	(43,601	)
	Less:
	Managing Member's interest		6,352			171			863

	Net earnings (loss) attributable to common and subordinated unitholders	$	(344,304	)	$	(8,786	)	$	(42,738	)


	Denominator:
	Basic:
	Weighted average units outstanding		36,882,713			34,941,036			68,296,990
	Diluted:
	Diluted:
	Weighted average units outstanding		36,882,713			34,941,036			68,296,990
	Earnings (loss) per unit allocated to common unitholders
	—basic and diluted	$	(9.34	)	$	(0.25	)	$	(0.63	)


	Earnings (loss) per unit allocated to subordinated unitholders
	—basic and diluted	$	—		$	—		$	(0.63	)




Unit-based Awards Outstanding
Unit-based compensation
Schedule of reconciliation of unit-based awards outstanding and nonvested unit-based awards

		Number of			Number of			Total Units
		Time-Based			Performance-
		Units			Based Units
	Unit-based awards outstanding—beginning of the year		835,360			487,200			1,322,560
	Granted		914,045			—			914,045
	Exercised		(501,883	)		(238,204	)		(740,087	)
	Forfeited		(161,597	)		(64,638	)		(226,235	)
	Distribution equivalent rights		113,416			30,321			143,737

	Unit-based awards outstanding—end of the year		1,199,341			214,679			1,414,020





Nonvested Unit-based Awards
Unit-based compensation
Schedule of reconciliation of unit-based awards outstanding and nonvested unit-based awards

		Number of			Number of			Total Units
		Time-Based			Performance-
		Units			Based Units
	Non-vested unit-based awards—beginning of the year		466,858			312,764			779,622
	Granted		914,045			—			914,045
	Vested		(133,380	)		(63,769	)		(197,149	)
	Forfeited		(159,737	)		(62,778	)		(222,515	)
	Distribution equivalent rights		111,555			28,462			140,017

	Non-vested unit-based awards—end of the year		1,199,341			214,679			1,414,020

Revenues_Tables

Revenues (Tables)	12 Months Ended
Revenues (Tables)	Mar. 31, 2015
Revenues
Schedule of components of fee-based revenue

		Year ended March 31,
		2015			2014			2013
	Long-term contract revenue	$	80,781		$	83,940		$	108,615
	Short-term contract revenue		11,559			51,416			54,710

		$	92,340		$	135,356		$	163,325




Schedule of components of optimization, net

		Year ended March 31,
		2015			2014			2013
	Realized optimization, net	$	38,085		$	85,372		$	89,525
	Unrealized risk management gains (loss) (Notes 12 and 13)		31,694			(8,732	)		(89,874	)
	Write-downs of inventory		(63,800	)		(4,600	)		(22,281	)

		$	5,979		$	72,040		$	(22,630	)

Depreciation_and_Amortization_

Depreciation and Amortization (Tables)	12 Months Ended
Depreciation and Amortization (Tables)	Mar. 31, 2015
Depreciation and Amortization
Schedule of depreciation and amortization

		Year ended March 31,
		2015		2014		2013
	Depreciation	$	93,190	$	30,636	$	38,901
	Amortization of intangible assets		23,633		10,543		11,311
	Accretion of asset retirement obligations		500		107		197

	Total	$	117,323	$	41,286	$	50,409

Interest_Tables

Interest (Tables)	12 Months Ended
Interest (Tables)	Mar. 31, 2015
Interest
Schedule of reconciliation of interest expense

		Year ended March 31,
		2015		2014		2013
	Gross interest	$	47,684	$	62,961	$	66,527
	Amortization of deferred financing costs		3,652		3,354		3,411
	Capitalized interest		—		—		(2,928	)

		$	51,336	$	66,315	$	67,010

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
Commitments and Contingencies (Tables)	Mar. 31, 2015
Commitments and Contingencies
Schedule of future minimum lease payments

	For the fiscal year ending:	Operating
	For the fiscal year ending:	leases
	2016	$	11,302
	2017		10,798
	2018		7,840
	2019		6,557
	2020		5,285
	2021 and thereafter		177,560

	Total minimum lease payments	$	219,342




Schedule of purchase obligations arising as a result of forward purchase contracts in place

	For the fiscal year ending:	Unconditional
		purchase
		obligations
	2016	$	981,883
	2017		192,618
	2018		299,210
	2019		8,579
	2020		2,519

	Total future purchase commitments	$	1,484,809

Changes_in_NonCash_Working_Cap1

Changes in Non-Cash Working Capital (Tables)	12 Months Ended
Changes in Non-Cash Working Capital (Tables)	Mar. 31, 2015
Changes in Non-Cash Working Capital
Schedule of changes in non-cash working capital

		Year ended March 31,
		2015			2014			2013
	Margin deposits	$	19,342		$	(14,137	)	$	(39,174	)
	Trade receivables		3,114			(3,383	)		(286	)
	Accrued receivables		110,484			(44,459	)		(40,203	)
	Natural gas inventory		(124,955	)		3,676			125,042
	Prepaid expenses and other current assets		542			358			(1,527	)
	Other assets		(517	)		(807	)		(1,105	)
	Trade payables		(212	)		(149	)		645
	Accrued liabilities		(63,709	)		68,106			8,927
	Deferred revenue		596			5,468			(10,667	)
	Other long-term liabilities		(520	)		360			381

	Net changes in non-cash working capital	$	(55,835	)	$	15,033		$	42,033

Supplemental_Cash_Flow_Disclos1

Supplemental Cash Flow Disclosures (Tables)	12 Months Ended
Supplemental Cash Flow Disclosures (Tables)	Mar. 31, 2015
Supplemental Cash Flow Disclosures
Schedule of supplemental cash flow disclosures

		Year ended March 31,
		2015		2014			2013
	Interest paid	$	30,083	$	63,769		$	67,408
	Taxes paid (received)		50		73			(722	)
	Interest capitalized		—		—			2,928
	Non-cash investing activities:
	Non-cash investing activities:
	Non-cash increase (decrease) in working capital related to property, plant and equipment	$	2,203	$	(2,426	)	$	(8,605	)
	Non-cash transfer of natural gas inventory to cushion		—		15,264			—
	Non-cash financing activities:
	Non-cash distributions and reinvestments		19,631		18,270			—

Segment_Disclosures_Tables

Segment Disclosures (Tables)	12 Months Ended
Segment Disclosures (Tables)	Mar. 31, 2015
Segment Disclosures
Summary of net revenues and long-lived assets by geographic area

		Year ended March 31,
		2015			2014			2013
	Net realized revenues
	U.S.	$	32,265		$	58,128		$	73,905
	Canada		98,160			162,600			178,945
	Net unrealized revenues
	U.S.		20,452			142			(37,139	)
	Canada		11,242			(8,874	)		(52,735	)
	Write-downs of inventory
	U.S.		(22,600	)		(500	)		(3,744	)
	Canada		(41,200	)		(4,100	)		(18,537	)
	Inter-entity
	U.S.		(4,266	)		—			—
	Canada		4,266			—			—

		$	98,319		$	207,396		$	140,695




		As at March 31,
		2015			2014
	Long-lived assets
	U.S.	$	367,920		$	397,331
	Canada		508,706			839,917

		$	876,626		$	1,237,248

Quarterly_Financial_Data_Table

Quarterly Financial Data (Tables)	12 Months Ended
Quarterly Financial Data (Tables)	Mar. 31, 2015
Quarterly Financial Data
Summary of quarterly financial data

		First			Second			Third			Fourth			Year ended
		Quarter			Quarter			Quarter			Quarter			March 31,
		(unaudited)			(unaudited)			(unaudited)			(unaudited)
	Fiscal 2015
	Revenue, net	$	55,377		$	10,590		$	39,219		$	(6,867	)	$	98,319
	Earnings (loss) before income taxes		(27,864	)		(36,180	)		(275,258	)		(43,010	)		(382,312	)
	Net earnings (loss) and comprehensive income (loss)		(18,972	)		(28,832	)		(259,623	)		(43,229	)		(350,656	)
	Earnings (loss) per unit		(0.52	)		(0.78	)		(6.85	)		(1.12	)		(9.34	)
	Fiscal 2014
	Fiscal 2014
	Revenue, net	$	57,189		$	36,863		$	25,847		$	87,497		$	207,396
	Earnings (loss) before income taxes		7,667			(7,797	)		(19,718	)		635			(19,213	)
	Net earnings (loss) and comprehensive income (loss)		7,967			(7,845	)		(13,409	)		4,330			(8,957	)
	Earnings (loss) per unit		0.23			(0.22	)		(0.37	)		0.12			(0.25	)

Description_of_Business_Detail

Description of Business (Details) (USD $)	12 Months Ended	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Jun. 30, 2015	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Members' equity
Common units outstanding	37,988,724		35,745,060	34,492,245	34,492,245
Managing member's interest (as a percent)	1.80%
Sponsor Holdings
Members' equity
Common units outstanding	20,488,525
Managing member's interest (as a percent)	1.80%
Ownership interest (as a percent)	54.76%
Public owners
Members' equity
Common units outstanding	17,500,199
Ownership interest (as a percent)	45.24%
Line of Credit \| Credit Agreement \| Revolving credit facilities
Members' equity
Maximum borrowing capacity	400
Maintenance of a fixed charge coverage ratio	1.1
Borrowing base becoming unavailable for borrowing due to change in fixed charge coverage ratio	15.00%
Line of Credit \| Credit Agreement \| Revolving credit facilities \| Maximum \| Forecast
Members' equity
Maintenance of a fixed charge coverage ratio		1.1

Significant_Accounting_Policie3

Significant Accounting Policies (Details)	12 Months Ended
	Mar. 31, 2015
	item
Revenue recognition
Number of revenue recognition criteria	4
Pipelines and measurement
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	5.00%
Wells
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	5.00%
Facilities \| Minimum
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	5.00%
Facilities \| Maximum
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	22.00%
Computer hardware and software
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	30.00%
Office furniture and fixtures
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	20.00%
Other
Property, plant and equipment
Depreciation rate declining balance method (as a percent)	10.00%

Significant_Accounting_Policie4

Significant Accounting Policies (Details 2) (Unit-based Awards)	12 Months Ended
	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common units permitted to be received by the unit award holder on the vesting date	1
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period over which units vest	2 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period over which units vest	3 years

Property_Plant_and_Equipment_D

Property, Plant and Equipment (Details) (USD $)	12 Months Ended
Property, Plant and Equipment (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Property, plant and equipment
Cost	$1,065,807,000	$1,125,175,000
Accumulated Depreciation	-245,340,000	-216,901,000
Net Book Value	820,467,000	908,274,000
Depreciation and amortization (Notes 4, 5 and 16)	117,323,000	41,286,000	50,409,000
Sundance Project \| Minimum \| Forecast
Property, plant and equipment
Working gas storage capacity	55,000
Sundance Project \| Maximum \| Forecast
Property, plant and equipment
Working gas storage capacity	70,000
U.S.
Property, plant and equipment
Number of facilities which sold cushion			1
Canada
Property, plant and equipment
Number of facilities which sold cushion			1
Cushion
Property, plant and equipment
Cost	356,655,000	421,404,000
Net Book Value	356,655,000	421,404,000
Loss on sale of cushion			14,900,000
Pipelines and measurement
Property, plant and equipment
Cost	296,669,000	296,671,000
Accumulated Depreciation	-102,885,000	-92,687,000
Net Book Value	193,784,000	203,984,000
Wells
Property, plant and equipment
Cost	127,297,000	126,694,000
Accumulated Depreciation	-45,004,000	-40,700,000
Net Book Value	82,293,000	85,994,000
Facilities
Property, plant and equipment
Cost	276,892,000	272,645,000
Accumulated Depreciation	-92,473,000	-79,028,000
Net Book Value	184,419,000	193,617,000
Cost of assets under capital lease	14,200,000	14,200,000
Accumulated depreciation of assets under capital lease	6,600,000	4,500,000
Cost of major overhauls of engines and compressors	2,400,000	300,000
Accumulated depreciation for major overhauls of engines and compressors	100,000
Computer hardware and software
Property, plant and equipment
Cost	4,293,000	4,225,000
Accumulated Depreciation	-3,440,000	-3,087,000
Net Book Value	853,000	1,138,000
Construction in progress, including projects under development
Property, plant and equipment
Cost	1,486,000	1,063,000
Net Book Value	1,486,000	1,063,000
Office furniture, equipment and other
Property, plant and equipment
Cost	2,515,000	2,473,000
Accumulated Depreciation	-1,538,000	-1,399,000
Net Book Value	$977,000	$1,074,000

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
		item	item	item
		segment
Goodwill and Other Intangible Assets
Number of reporting units		4
Number of reportable segments		1	1	1
Impairment charge of long-lived assets		$0
Goodwill [Roll Forward]
Balance at the beginning of the period		245,604
Impairment charges	-245,600	-245,604
Balance at the end of the period			245,604
AECO Hub Facility
Goodwill [Roll Forward]
Balance at the beginning of the period		228,004
Impairment charges		-228,004
Wild Goose Facility
Goodwill [Roll Forward]
Balance at the end of the period		0
Salt Plains Facility
Goodwill [Roll Forward]
Balance at the end of the period		0
NGPL Leased Capacity
Goodwill [Roll Forward]
Balance at the beginning of the period		17,600
Impairment charges		($17,600)

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2015
Other intangible assets
Customer contracts and relationships, beginning of the year	$163,073	165,080
Additions	2,007
Less accumulated amortization	-117,888	-141,521
Customer contracts and relationships, end of the year	47,192	23,559
Pipeline rights of way	18,270	18,270
Total	$65,462	41,829
Minimum
Other intangible assets
Term of contracts		1 year
Maximum
Other intangible assets
Term of contracts		9 years

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Goodwill and Other Intangible Assets
Amortization expense	$23,633	$10,543	$11,311
Estimated future amortization expense
31-Mar-16	5,977
31-Mar-17	7,513
31-Mar-18	3,558
31-Mar-19	3,341
March 31, 2020 and thereafter	$3,170

Deferred_Financing_Costs_Detai

Deferred Financing Costs (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Deferred financing costs
Deferred financing costs, beginning of the year	$20,078	$25,377
Additions	13	11,696
Write-off due to extinguishment of debt		-16,995
Deferred financing costs, end of the year	20,091	20,078	25,377
Accumulated amortization, beginning of the year	-5,438	-10,957
Amortization recognized as interest (see Note 17)	-3,652	-3,354	-3,411
Write-off due to extinguishment of debt		8,873
Accumulated amortization, end of the year	-9,090	-5,438	-10,957
Net book value	11,001	14,640
Life in years, minimum	2 years	3 years
Life in years, maximum	4 years	5 years
Amortization expense
Amortization expense	$3,652	$3,354	$3,411

Debt_Details

Debt (Details) (USD $)	3 Months Ended	12 Months Ended			1 Months Ended
	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014
	Mar. 31, 2014	item	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014
Debt
Long-term debt	$575,000,000	$575,000,000	$575,000,000		$575,000,000
Revolving credit facilities	119,500,000	193,500,000	119,500,000		119,500,000
Total	694,500,000	768,500,000	694,500,000		694,500,000
Long-term debt, less current portion	575,000,000	575,000,000	575,000,000		575,000,000
Loss on extinguishment of debt	-36,700,000		-36,697,000	-599,000
Minimum fixed charge coverage ratio required to make restricted payments		1.75
Actual fixed charge coverage ratio		1.3
Letters of credit issued		5,800,000
Number of independent assets or operations other than investments in subsidiaries		0
Restricted assets		0
Debt redemption / repurchase			672,361,000
Credit Agreement \| Line of Credit \| Revolving credit facilities
Debt
Revolving credit facilities	119,500,000	193,500,000	119,500,000		119,500,000
Maximum borrowing capacity		400,000,000
Borrowing base collateral		294,400,000
Weighted average interest rate (as a percent)	3.56%	3.98%	3.56%		3.56%
Letters of credit issued	4,800,000	5,800,000	4,800,000		4,800,000
Amount included in aggregate borrowing base under the Credit Facilities due to a first-priority lien on fixed assets granted to the lenders		150,000,000
Minimum amount of release from the first-priority lien for reduction in fixed assets amount on a dollar-for-dollar basis		50,000,000
Minimum fixed charge coverage ratio required to be maintained when excess availability under both facilities is less than 15% of the aggregate amount of availability		1.1
Credit Agreement \| U.S. revolving credit facility \| Revolving credit facilities
Debt
Maximum borrowing capacity		200,000,000
Amount by which maximum borrowing capacity may be expanded in additional commitments		100,000,000
Minimum fixed charge coverage ratio required to be maintained when excess availability under both facilities is less than 15% of the aggregate amount of availability		1.1
Period of consecutive time that excess availability exceeds 15% to release quarterly testing of the 1.1 to 1.0 fixed charge coverage ratio		30 days
Credit Agreement \| Canadian revolving credit facility \| Revolving credit facilities
Debt
Maximum borrowing capacity		200,000,000
Amount by which maximum borrowing capacity may be expanded in additional commitments		100,000,000
Minimum fixed charge coverage ratio required to be maintained when excess availability under both facilities is less than 15% of the aggregate amount of availability		1.1
Period of consecutive time that excess availability exceeds 15% to release quarterly testing of the 1.1 to 1.0 fixed charge coverage ratio		30 days
Maximum
Debt
Fixed charge coverage ratio required to incur additional debt obligations		2
Maximum \| Credit Agreement \| U.S. revolving credit facility \| Revolving credit facilities
Debt
Level of available Credit Facilities under both the U.S. revolving facility and the Canadian revolving credit facility at the end of each fiscal quarter when the maintenance of a fixed charge coverage ratio of 1.1 to 1.0 is not required		15.00%
Maximum \| Credit Agreement \| Canadian revolving credit facility \| Revolving credit facilities
Debt
Level of available Credit Facilities under both the U.S. revolving facility and the Canadian revolving credit facility at the end of each fiscal quarter when the maintenance of a fixed charge coverage ratio of 1.1 to 1.0 is not required		15.00%
Senior Notes \| 6.50 % Senior Notes due 2019
Debt
Long-term debt	575,000,000	575,000,000	575,000,000		575,000,000
Net proceeds from issuance of debt					563,300,000
Interest rate (as a percent)	6.50%	6.50%	6.50%		6.50%
Estimated fair market value of debt		432,700,000
Redemption price as a percentage of principal amount upon occurrence of change of control		101.00%
Amount included in the general basket of restricted payments		75,000,000
Percentage of aggregate principal amount of notes that holders can request for accelerated payment in case of an event of default		25.00%
Period upon occurrence of change of control used to determine redemption of debt		90 days
Senior Notes \| 8.875% Senior Notes due 2018
Debt
Long-term debt				643,800,000
Interest rate (as a percent)	8.88%		8.88%	8.88%	8.88%
Payment of call premium					28,600,000
Write-off of unamortized deferred financing costs					8,100,000
Loss on extinguishment of debt					-36,700,000
Debt redemption / repurchase					$643,800,000
Prior to October 1, 2016 \| Senior Notes \| 6.50 % Senior Notes due 2019
Debt
Redemption price as a percentage of principal amount		106.50%
Prior to October 1, 2016 \| Senior Notes \| Maximum \| 6.50 % Senior Notes due 2019
Debt
Percentage of aggregate principal amount that may be redeemed		35.00%
Twelve-month period beginning on October 1, 2016 \| Senior Notes \| 6.50 % Senior Notes due 2019
Debt
Redemption price as a percentage of principal amount		103.25%
Twelve-month period beginning on October 1, 2017 and at par beginning on October 1, 2018 \| Senior Notes \| 6.50 % Senior Notes due 2019
Debt
Redemption price as a percentage of principal amount		101.63%

Obligations_Under_Capital_Leas2

Obligations Under Capital Lease (Details) (USD $)	12 Months Ended
Obligations Under Capital Lease (Details) (USD $)	Mar. 31, 2015
Obligations Under Capital Lease
Estimated future minimum lease payments	$12,200,000
Imputed interest rate (as a percent)	3.08%
Future principal and interest payments of obligations under capital lease
31-Mar-16	1,657,000
31-Mar-17	1,657,000
31-Mar-18	1,657,000
31-Mar-19	1,657,000
31-Mar-20	1,657,000
March 31, 2021 and thereafter	3,917,000
Less: Amount representing interest	-1,276,000
Total	$10,926,000

Accrued_Liabilities_Details

Accrued Liabilities (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Accrued Liabilities
Accrued interest	$21,411	$2,037
Accrued gas purchases	13,917	75,454
Employee-related accruals	2,369	22,315
Other accrued liabilities	9,989	11,312
Total	$47,686	$111,118

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	12 Months Ended
Asset Retirement Obligations (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Asset Retirement Obligations
Estimated undiscounted cash flows required to settle the asset retirement obligations	$58,500,000
Inflation rate used in calculation of undiscounted cash flows required to settle the asset retirement obligations (as a percent)	2.00%
Rate used to discount estimated cash flows (as a percent)	8.00%
Period for payment for settlement of the obligations	42 years
Changes in asset retirement obligations
Balance, beginning of the year	1,975,000	2,007,000
Additions	22,000
Accretion	500,000	107,000	197,000
Effect of foreign exchange translation	-189,000	-139,000
Balance, end of the year	$2,308,000	$1,975,000	$2,007,000

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Components of earnings (loss) before income taxes
Domestic									$6,506	$16,844	($493)
Foreign									-388,818	-36,057	-62,050
EARNINGS (LOSS) BEFORE INCOME TAXES	-43,010	-275,258	-36,180	-27,864	635	-19,718	-7,797	7,667	-382,312	-19,213	-62,543
Total income tax expense (benefit) differed from the amounts computed by applying the tax rate to earnings (loss) before income taxes
Earnings (loss) before taxes	-43,010	-275,258	-36,180	-27,864	635	-19,718	-7,797	7,667	-382,312	-19,213	-62,543
U.S. federal corporate statutory rate (as a percent)									35.00%	35.00%	35.00%
Expected tax benefits									-133,809	-6,725	-21,890
Non-deductible expense related to asset impairment									57,001
Canadian statutory tax rate differences									39,056	3,559	6,145
Adjustments and assessments									2,592	-690	-4,796
Change in valuation allowance									2,314	-1,248	-452
Earnings (loss) of non-taxable entities									-1,925	-6,296	1,377
Non-deductible expenses and other									3,115	1,144	674
Income tax expense (benefit)									($31,656)	($10,256)	($18,942)

Income_Taxes_Details_2

Income Taxes (Details 2) (USD $)	12 Months Ended
Income Taxes (Details 2) (USD $)	Mar. 31, 2015	Mar. 31, 2014
Capital losses
Deferred tax asset resulted from capital losses	$4,223,000	$2,358,000
Deferred income tax assets resulting from non-capital loss carryforwards	18,959,000	18,434,000
Potential interest and penalties associated with uncertain tax positions
Potential interest and penalties associated with uncertain tax positions	100,000
Deferred income tax assets:
Non-capital loss carry forwards	18,959,000	18,434,000
Risk management liabilities	19,919,000	33,386,000
Capital losses	4,223,000	2,358,000
Deferred financing costs	4,006,000	6,890,000
Other	2,774,000	2,403,000
Total	49,881,000	63,471,000
Valuation allowance	-7,173,000	-4,004,000
Total deferred income tax assets	42,708,000	59,467,000
Deferred income tax liabilities:
Property, plant and equipment	99,628,000	114,298,000
Risk management assets	24,202,000	17,049,000
Intangible assets	9,510,000	15,137,000
Partnership deferral income		37,499,000
Other	19,000	535,000
Total deferred income tax liabilities	133,359,000	184,518,000
Net deferred income tax liabilities	90,651,000	125,051,000
Deferred income tax liabilities:
Current	2,334,000	5,678,000
Long-term	88,317,000	119,373,000
Net deferred income tax liabilities	90,651,000	125,051,000
Changes to the Company's unrecognized tax benefits
Balance at beginning of the year	1,735,000	1,160,000
Additions based on tax positions taken in the current year		375,000
(Reductions) additions based on tax positions taken in a prior year	-205,000	200,000
Balance at end of the year	1,530,000	1,735,000
Unrecognized tax benefits that would have an impact on the effective tax rate if subsequently recognized	1,500,000
Unrecognized tax benefits expected to be recognized within the next twelve months	0
Canadian subsidiaries
Capital losses
Accumulated non-capital losses	76,400,000	76,200,000
Deferred income tax assets resulting from non-capital loss carryforwards	19,000,000	18,400,000
Deferred income tax assets:
Non-capital loss carry forwards	19,000,000	18,400,000
Canadian subsidiaries \| Capital losses
Capital losses
Capital losses	33,800,000	18,900,000
Deferred tax asset resulted from capital losses	4,200,000	2,400,000
Amount of capital losses offset by valuation allowance	4,200,000	2,400,000
Amount of tax assets related to losses expiring at the end of 2031	500,000
Deferred income tax assets:
Capital losses	$4,200,000	$2,400,000

Risk_Management_Activities_and2

Risk Management Activities and Financial Instruments (Details) (USD $)	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
	item	item	Mar. 31, 2013
Risk management activities and financial instruments
Doubtful account expense recognized on trade receivable deemed to be uncollectible	$0	$400,000
Number of significant counterparties	1
Percentage of total revenue from one counterparty	54.00%	56.00%	28.00%
Revolving credit facilities	193,500,000	119,500,000
Number of interest rate swap or swaption agreements	0	0
Minimum \| Natural gas retail contracts
Risk management activities and financial instruments
Period of energy contracts to customers in retail markets	1 year	1 year
Maximum \| Natural gas retail contracts
Risk management activities and financial instruments
Period of energy contracts to customers in retail markets	5 years	5 years
Exchange traded futures and options
Risk management activities and financial instruments
Exchange traded derivative instruments as a percentage of commodity risk management assets	69.00%
Commodity Derivatives
Risk management activities and financial instruments
Aggregate overall exposure limit of unmatched volumes of proprietary current natural gas inventory (in million cubic feet)	8,000
Volume of current natural gas inventory offset with financial contracts (in million cubic feet)	47,200	18,400
Percentage of the total inventory of natural gas offset with financial contracts	98.60%
Commodity Derivatives \| Natural gas retail contracts
Risk management activities and financial instruments
Reduction in value of energy contracts due to credit exposure	1,700,000
Commodity Derivatives \| Forward contracts
Risk management activities and financial instruments
Volume of current natural gas inventory offset with financial contracts (in million cubic feet)	1,500	-1,400
Commodity Derivatives \| Futures
Risk management activities and financial instruments
Volume of current natural gas inventory offset with financial contracts (in million cubic feet)	46,000	20,100
Commodity Derivatives \| Swaps
Risk management activities and financial instruments
Volume of current natural gas inventory offset with financial contracts (in million cubic feet)	-300	-300
Currency Derivatives \| Currency swap
Risk management activities and financial instruments
Notional value of currency swaps	19,600,000	13,000,000
Revolving credit facilities \| Line of Credit \| Credit Agreement
Risk management activities and financial instruments
Maximum borrowing capacity	400,000,000
Revolving credit facilities	193,500,000	119,500,000
Revolving credit facilities \| U.S. revolving credit facility \| Credit Agreement
Risk management activities and financial instruments
Maximum borrowing capacity	200,000,000
Revolving credit facilities \| Canadian revolving credit facility \| Credit Agreement
Risk management activities and financial instruments
Maximum borrowing capacity	$200,000,000

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair value of risk management assets and liabilities
Short-term risk management assets	$41,600	$20,949
Long-term risk management assets	30,928	4,806
Short-term risk management liabilities	-25,560	-19,105
Long-term risk management liabilities	-20,833	-12,209
Total	26,135	-5,559
Not designated as hedge
Fair value of risk management assets and liabilities
Short-term risk management assets	41,600	20,949
Long-term risk management assets	30,928	4,806
Short-term risk management liabilities	-25,560	-19,105
Long-term risk management liabilities	-20,833	-12,209
Total	26,135	-5,559
Commodity Derivatives
Fair value of risk management assets and liabilities
Total	22,967
Commodity Derivatives \| Not designated as hedge
Fair value of risk management assets and liabilities
Short-term risk management assets	39,392	18,939
Long-term risk management assets	29,647	4,260
Short-term risk management liabilities	-25,560	-18,945
Long-term risk management liabilities	-20,512	-12,209
Total	22,967	-7,955
Currency Derivatives
Fair value of risk management assets and liabilities
Total	3,168
Currency Derivatives \| Not designated as hedge
Fair value of risk management assets and liabilities
Short-term risk management assets	2,208	2,010
Long-term risk management assets	1,281	546
Short-term risk management liabilities		-160
Long-term risk management liabilities	-321
Total	$3,168	$2,396

Fair_Value_Measurements_Detail1

Fair Value Measurements (Details 2) (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Assets
Gross Amounts Recognized	$153,552	$116,026
Gross Amounts Offset in the Balance Sheet	-81,024	-90,271
Net Amounts Presented in the Balance Sheet	72,528	25,755
Margin Deposits not Offset in the Balance Sheet	-50,070	-17,657
Net Amounts	22,458	8,098
Liabilities
Gross Amounts Recognized	127,417	121,585
Gross Amounts Offset in the Balance Sheets	-81,024	-90,271
Net Amounts Presented in the Balance Sheets	46,393	31,314
Margin Deposits not Offset in the Balance Sheets	-39,659	-21,865
Net Amounts	6,734	9,449
Net - Amounts Presented in the Balance Sheets	26,135	-5,559
Net - Margin Deposits not Offset in the Balance Sheets	-10,411	4,208
Net	15,724	-1,351
Commodity Derivatives
Assets
Gross Amounts Recognized	148,385	113,175
Gross Amounts Offset in the Balance Sheet	-79,346	-89,976
Net Amounts Presented in the Balance Sheet	69,039	23,199
Margin Deposits not Offset in the Balance Sheet	-50,070	-15,101
Net Amounts	18,969	8,098
Liabilities
Gross Amounts Recognized	125,418	121,130
Gross Amounts Offset in the Balance Sheets	-79,346	-89,976
Net Amounts Presented in the Balance Sheets	46,072	31,154
Margin Deposits not Offset in the Balance Sheets	-39,338	-21,705
Net Amounts	6,734	9,449
Net - Amounts Presented in the Balance Sheets	22,967
Currency Derivatives
Assets
Gross Amounts Recognized	5,167	2,851
Gross Amounts Offset in the Balance Sheet	-1,678	-295
Net Amounts Presented in the Balance Sheet	3,489	2,556
Margin Deposits not Offset in the Balance Sheet		-2,556
Net Amounts	3,489
Liabilities
Gross Amounts Recognized	1,999	455
Gross Amounts Offset in the Balance Sheets	-1,678	-295
Net Amounts Presented in the Balance Sheets	321	160
Margin Deposits not Offset in the Balance Sheets	-321	-160
Net - Amounts Presented in the Balance Sheets	$3,168

Fair_Value_Measurements_Detail2

Fair Value Measurements (Details 3) (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Expected realization of derivative instruments into earnings
Fiscal year ending March 31, 2016	$16,040
Fiscal year ending March 31, 2017 and beyond	10,095
Total	26,135	-5,559
Commodity Derivatives
Expected realization of derivative instruments into earnings
Fiscal year ending March 31, 2016	13,832
Fiscal year ending March 31, 2017 and beyond	9,135
Total	22,967
Currency Derivatives
Expected realization of derivative instruments into earnings
Fiscal year ending March 31, 2016	2,208
Fiscal year ending March 31, 2017 and beyond	960
Total	$3,168

Fair_Value_Measurements_Detail3

Fair Value Measurements (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Net realized and unrealized optimization gains and losses from the settlement of risk management contracts
Unrealized	$31,694	($8,732)	($89,851)
Not designated as hedge
Net realized and unrealized optimization gains and losses from the settlement of risk management contracts
Total	74,940	-84,333	-47,170
Commodity Derivatives \| Not designated as hedge
Net realized and unrealized optimization gains and losses from the settlement of risk management contracts
Realized	40,787	-78,778	41,304
Unrealized	30,922	-10,662	-90,641
Currency Derivatives \| Not designated as hedge
Net realized and unrealized optimization gains and losses from the settlement of risk management contracts
Realized	2,459	3,177	1,377
Unrealized	$772	$1,930	$790

Fair_Value_Measurements_Detail4

Fair Value Measurements (Details 5) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Assets
Total assets	$72,528	$25,755
Liabilities
Transfer out of Level 2	0	0	0
Transfer out of Level 2	0	0	0
Non-financial assets	0	0
Non-financial liabilities	0	0
Commodity Derivatives
Assets
Total assets	69,039	23,199
Currency Derivatives
Assets
Total assets	3,489	2,556
Recurring and Non Recurring \| Level 2
Assets
Total assets	72,528	25,755
Liabilities
Long-term debt	432,688	570,700
Total liabilities	479,081	602,014
Recurring and Non Recurring \| Level 2 \| Commodity Derivatives
Assets
Total assets	69,039	23,199
Liabilities
Total liabilities	46,072	31,154
Recurring and Non Recurring \| Level 2 \| Currency Derivatives
Assets
Total assets	3,489	2,556
Liabilities
Total liabilities	321	160
Recurring and Non Recurring \| Total
Assets
Total assets	72,528	25,755
Liabilities
Long-term debt	432,688	570,700
Total liabilities	479,081	602,014
Recurring and Non Recurring \| Total \| Commodity Derivatives
Assets
Total assets	69,039	23,199
Liabilities
Total liabilities	46,072	31,154
Recurring and Non Recurring \| Total \| Currency Derivatives
Assets
Total assets	3,489	2,556
Liabilities
Total liabilities	$321	$160

Members_Equity_Details

Members' Equity (Details) (USD $)	0 Months Ended	12 Months Ended			0 Months Ended
Members' Equity (Details) (USD $)	Oct. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Apr. 02, 2013	Mar. 31, 2012	Jul. 31, 2013
Members' Equity
Common units issued under DRIP		2,243,664	1,252,815
Non-cash distributions and reinvestments		$19,631,000	$18,270,000
Additional value of common units allowed to be issued	75,000,000
Common units issued under the At-The-Market program		0
Period a member who received impermissible distribution will be liable		3 years
Subordinated units issued				33,804,745		33,804,745
Subordinated units cancelled					-33,804,745
Total units issued		2,243,664	1,252,815
Common units outstanding		37,988,724	35,745,060	34,492,245		34,492,245
Total Units outstanding		37,988,724	35,745,060	68,296,990		68,296,990
Managing member's interest (as a percent)		1.80%
Period after the end of each quarter within which available cash is distributed to unitholders		45 days
Gross distribution made to the holders of common units and the Managing Member		39,700,000	52,300,000
Additional disclosures
Number of equity awards settled during the period		0	0	0
Sponsor Holdings
Members' Equity
Managing member's interest (as a percent)		1.80%
Unit-based Awards Outstanding
Members' Equity
Weighted average price of granted unit-based awards (in dollars per share)		$9.43	$12.68	9.99
Reconciliation of Unit-based Awards Outstanding
Granted (in shares)		914,045	438,036	695,349
Unit-based Awards
Members' Equity
Number of common units that could be delivered under the Plans		3,380,474
Number of common units available for delivery under the Plans		3,303,473	3,319,503
Number of common units permitted to be received by the unit award holder on the vesting date		1
Additional disclosures
Unit-based compensation (recovery) expense		-1,600,000	11,200,000	7,000,000
Cash paid to employees who exercised unit-based awards		10,600,000	2,300,000
Unit-based Awards \| Unit-based Awards Outstanding
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)		1,322,560
Granted (in shares)		914,045
Exercised (in shares)		-740,087
Forfeited (in shares)		-226,235
Distribution equivalent rights (in shares)		143,737
Balance at the end of the year (in shares)		1,414,020
Unit-based Awards \| Nonvested Unit-based Awards
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)		779,622
Granted (in shares)		914,045
Vested (in shares)		-197,149
Forfeited (in shares)		-222,515
Distribution equivalent rights (in shares)		140,017
Balance at the end of the year (in shares)		1,414,020
Additional disclosures
Total unrecognized non-cash compensation cost		5,100,000	5,900,000
Expected period for unrecognized compensation cost to be recognized		3 years
Time-based Unit-based Awards \| Unit-based Awards Outstanding
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)		835,360
Granted (in shares)		914,045
Exercised (in shares)		-501,883
Forfeited (in shares)		-161,597
Distribution equivalent rights (in shares)		113,416
Balance at the end of the year (in shares)		1,199,341
Time-based Unit-based Awards \| Nonvested Unit-based Awards
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)		466,858
Granted (in shares)		914,045
Vested (in shares)		-133,380
Forfeited (in shares)		-159,737
Distribution equivalent rights (in shares)		111,555
Balance at the end of the year (in shares)		1,199,341
Performance-based Unit-based Awards \| Unit-based Awards Outstanding
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)		487,200
Exercised (in shares)		-238,204
Forfeited (in shares)		-64,638
Distribution equivalent rights (in shares)		30,321
Balance at the end of the year (in shares)		214,679
Performance-based Unit-based Awards \| Nonvested Unit-based Awards
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)		312,764
Vested (in shares)		-63,769
Forfeited (in shares)		-62,778
Distribution equivalent rights (in shares)		28,462
Balance at the end of the year (in shares)		214,679
Class D Units
Members' Equity
Distribution as a percentage in excess of the Partnership's Class A unitholder's capital contributions		15.00%
Minimum required distribution to Class A unitholders before the Class D Units are entitled to distributions		331,000,000
Annual distribution increase compounded quarterly (as a percent)		8.00%
Additional disclosures
Unit-based compensation (recovery) expense		500,000
Award vesting on May 6, 2015 \| Class D Units
Members' Equity
Vesting Percentage		20.00%
Award vesting on last day of each fiscal quarter during the period commencing on June 30, 2015 and through March 31, 2019 \| Class D Units
Members' Equity
Vesting Percentage		5.00%
Minimum
Members' Equity
Voting interest required for removal of manager prior to March 31, 2020 (as a percent)		66.67%
Ownership interest of manager and its affiliates that gives them ability to prevent the manager's removal (as a percent)		33.33%
Minimum \| Unit-based Awards
Members' Equity
Period over which units vest		2 years
Maximum
Members' Equity
Common units authorized under DRIP							7,500,000
Maximum \| Unit-based Awards
Members' Equity
Period over which units vest		3 years
Carlyle/Riverstone Funds
Members' Equity
Common units issued under DRIP		2,243,470	1,252,810
Non-cash distributions and reinvestments		19,600,000	18,300,000
New structure \| Carlyle/Riverstone Funds
Members' Equity
Period for which Carlyle Riverstone Funds will be deemed to own Notional Subordinated Units					5 years
Subordinated Units \| Previous structure
Members' Equity
Additional distributions per quarter prior to increasing the quarterly distribution on Niska Partners' common units					12,000,000
Subordinated Units \| Previous structure \| Carlyle/Riverstone Funds
Members' Equity
Subordinated units outstanding					33,800,000
Notional Subordinated Units \| New structure \| Carlyle/Riverstone Funds
Members' Equity
Notional Subordinated Units (in shares)					33,800,000
Minimum Quarterly Distribution \| Subordinated Units \| Previous structure
Members' Equity
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)					0.35
Unitholders \| Previous structure \| Minimum
Members' Equity
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)					0.4025
Unitholders \| Previous structure \| Maximum
Members' Equity
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)					0.525
Common Units
Members' Equity
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)		$0.35
Common Units \| Sponsor Holdings
Members' Equity
Ownership of common and notional subordinated units, excluding managing member interest (as a percent)		53.93%
Common Units \| Minimum Quarterly Distribution \| New structure
Members' Equity
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)					0.35
Distribution in arrears from prior quarters (in dollars per unit)					0
IDR Holder \| Previous structure \| Carlyle/Riverstone Funds \| Minimum
Members' Equity
Marginal Percentage Interest in Cash Distributions					13.00%
IDR Holder \| Previous structure \| Carlyle/Riverstone Funds \| Maximum
Members' Equity
Marginal Percentage Interest in Cash Distributions					48.00%
IDR Holder \| New structure \| Carlyle/Riverstone Funds
Members' Equity
Marginal Percentage Interest in Cash Distributions		48.00%

Members_Equity_Details_2

Members' Equity (Details 2) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Unit-based Awards Outstanding
Members' Equity
Weighted average price of granted unit-based awards (in dollars per share)	$9.43	$12.68	$9.99
Reconciliation of Unit-based Awards Outstanding
Granted (in shares)	914,045	438,036	695,349
Unit-based Awards
Members' Equity
Number of common units that could be delivered under the Plans	3,380,474
Number of common units available for delivery under the Plans	3,303,473	3,319,503
Number of units reserved for outstanding equity settled awards	808,081
Number of unit-based awards classified as a liability	701,285
Number of unit-based awards classified as equity	712,735
Number of unit-based awards classified as a liability that can be settled in cash or units	95,347
Additional disclosures
Unit-based compensation (recovery) expense	($1.60)	$11.20	$7
Cash paid to employees who exercised unit-based awards	10.6	2.3
Unit-based Awards \| Unit-based Awards Outstanding
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)	1,322,560
Granted (in shares)	914,045
Exercised (in shares)	-740,087
Forfeited (in shares)	-226,235
Distribution equivalent rights (in shares)	143,737
Balance at the end of the year (in shares)	1,414,020
Unit-based Awards \| Nonvested Unit-based Awards
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)	779,622
Granted (in shares)	914,045
Vested (in shares)	-197,149
Forfeited (in shares)	-222,515
Distribution equivalent rights (in shares)	140,017
Balance at the end of the year (in shares)	1,414,020
Additional disclosures
Total unrecognized non-cash compensation cost	$5.10	$5.90
Expected period for unrecognized compensation cost to be recognized	3 years
Time-based Unit-based Awards \| Unit-based Awards Outstanding
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)	835,360
Granted (in shares)	914,045
Exercised (in shares)	-501,883
Forfeited (in shares)	-161,597
Distribution equivalent rights (in shares)	113,416
Balance at the end of the year (in shares)	1,199,341
Time-based Unit-based Awards \| Nonvested Unit-based Awards
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)	466,858
Granted (in shares)	914,045
Vested (in shares)	-133,380
Forfeited (in shares)	-159,737
Distribution equivalent rights (in shares)	111,555
Balance at the end of the year (in shares)	1,199,341
Performance-based Unit-based Awards \| Unit-based Awards Outstanding
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)	487,200
Exercised (in shares)	-238,204
Forfeited (in shares)	-64,638
Distribution equivalent rights (in shares)	30,321
Balance at the end of the year (in shares)	214,679
Performance-based Unit-based Awards \| Nonvested Unit-based Awards
Reconciliation of Unit-based Awards Outstanding
Balance at the beginning of the year (in shares)	312,764
Vested (in shares)	-63,769
Forfeited (in shares)	-62,778
Distribution equivalent rights (in shares)	28,462
Balance at the end of the year (in shares)	214,679

Members_Equity_Details_3

Members' Equity (Details 3) (USD $)	3 Months Ended								12 Months Ended			0 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Apr. 02, 2013
Numerator:
NET EARNINGS (LOSS) AND COMPREHENSIVE INCOME (LOSS)	($43,229)	($259,623)	($28,832)	($18,972)	$4,330	($13,409)	($7,845)	$7,967	($350,656)	($8,957)	($43,601)
Less: Managing Member's interest									6,352	171	863
Net earnings (loss) attributable to common and subordinated unit holders									($344,304)	($8,786)	($42,738)
Basic:
Weighted average units outstanding (in shares)									36,882,713	34,941,036	68,296,990
Diluted:
Weighted average units outstanding (in shares)									36,882,713	34,941,036	68,296,990
Earnings (loss) per unit allocated to common and subordinated unitholders
Earnings (loss) per unit allocated to common unitholders - basic and diluted (in dollars per unit)									($9.34)	($0.25)	($0.63)
Earnings (loss) per unit allocated to subordinated unitholders - basic and diluted (in dollars per unit)											-0.63
Weighted average number of equity awards to be settled									451,001	0	0
IDR Holder \| Carlyle/Riverstone Funds \| New structure
Incentive distribution rights
Marginal Percentage Interest in Cash Distributions									48.00%
IDR Holder \| Minimum \| Carlyle/Riverstone Funds \| Previous structure
Incentive distribution rights
Marginal Percentage Interest in Cash Distributions												13.00%
IDR Holder \| Maximum \| Carlyle/Riverstone Funds \| Previous structure
Incentive distribution rights
Marginal Percentage Interest in Cash Distributions												48.00%
Unitholders \| Minimum \| Previous structure
Incentive distribution rights
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)												0.4025
Unitholders \| Maximum \| Previous structure
Incentive distribution rights
Total Quarterly Distribution per Unit Target Amount (in dollars per unit)												0.525

Revenues_Details

Revenues (Details) (USD $)	3 Months Ended					12 Months Ended
Revenues (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Fee-based Revenue
Long-term contract revenue						$80,781,000	$83,940,000	$108,615,000
Short-term contract revenue						11,559,000	51,416,000	54,710,000
Total						92,340,000	135,356,000	163,325,000
One-time contract termination payment				26,000,000		26,000,000
Optimization Revenue
Realized optimization revenue, net						38,085,000	85,372,000	89,525,000
Unrealized risk management gains (losses) (Notes 12 and 13)						31,694,000	-8,732,000	-89,874,000
Write-downs of inventory	-21,600,000	-31,700,000	-10,500,000		-4,600,000	-63,800,000	-4,600,000	-22,281,000
Total						$5,979,000	$72,040,000	($22,630,000)

Depreciation_and_Amortization_1

Depreciation and Amortization (Details) (USD $)	3 Months Ended			12 Months Ended
Depreciation and Amortization (Details) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Depreciation and Amortization
Depreciation				$93,190,000	$30,636,000	$38,901,000
Amortization of intangible assets				23,633,000	10,543,000	11,311,000
Accretion of asset retirement obligations				500,000	107,000	197,000
Total				117,323,000	41,286,000	50,409,000
Depreciation related to migration of cushion at two of the Company's facilities	$31,100,000	$5,700,000	$27,900,000	$64,700,000		$9,300,000

Depreciation_and_Amortization_2

Depreciation and Amortization (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$23,633	$10,543	$11,311
Prior storage service agreement
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$11,700

Interest_Details

Interest (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Interest
Gross interest	$47,684	$62,961	$66,527
Amortization of deferred financing costs	3,652	3,354	3,411
Capitalized interest			-2,928
Total	$51,336	$66,315	$67,010

Related_Party_Transactions_Det

Related Party Transactions (Details) (USD $)	12 Months Ended
Related Party Transactions (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Related Party Transactions
Amount owing to related parties		$0
Amount owing from related parties		0
Common units issued under DRIP	2,243,664	1,252,815
Non-cash distributions and reinvestments	19,631,000	18,270,000
Affiliated entities
Related Party Transactions
Management fees charged for administrative services rendered		200,000	200,000
Carlyle/Riverstone Funds
Related Party Transactions
Common units issued under DRIP	2,243,470	1,252,810
Non-cash distributions and reinvestments	19,600,000	18,300,000
Holdco
Related Party Transactions
Amount owing from related parties	$6,100,000

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Loss Contingencies
Loss contingency accrual	$6.10
Amount owing from related parties		0
Holdco
Loss Contingencies
Amount owing from related parties	6.1
Foreign Tax Authority \| Canadian Tax Authorities
Loss Contingencies
Estimated tax assessment, minimum	6.1
Estimated tax assessment, maximum	$10.60

Commitments_and_Contingencies_2

Commitments and Contingencies (Details 2) (USD $)	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
	item	Mar. 31, 2014	Mar. 31, 2013
Commitments and Contingencies
Term for which office lease can be extended	5 years
Future minimum lease payments
2016	$11,302,000
2017	10,798,000
2018	7,840,000
2019	6,557,000
2020	5,285,000
2021 and thereafter	177,560,000
Total minimum lease payments	219,342,000
Total minimum rentals to be received in the future under non-cancelable subleases	1,600,000
Sublease recoveries	700,000
Lease and rental expense, net of sublease recoveries	13,600,000	11,900,000	11,200,000
Contingent rent included in lease and rental expense		400,000	300,000
Unconditional purchase obligations
2016	981,883,000
2017	192,618,000
2018	299,210,000
2019	8,579,000
2020	2,519,000
Total future purchase commitments	1,484,809,000
Forward physical and financial sales for all future periods	1,485,300,000
Issued and outstanding letter of credit to counterparties to support natural gas purchase commitments	5,800,000
Number of Canadian subsidiaries that owe certain interest payable to a non-Canadian affiliate	1
Payment of withholding taxes to Canadian tax authorities on behalf of unitholders in fiscal 2016	$4,100,000

Changes_in_NonCash_Working_Cap2

Changes in Non-Cash Working Capital (Details) (USD $)	12 Months Ended
Changes in Non-Cash Working Capital (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Changes in Non-Cash Working Capital
Margin deposits	$19,342,000	($14,137,000)	($39,174,000)
Trade receivables	3,114,000	-3,383,000	-286,000
Accrued receivables	110,484,000	-44,459,000	-40,203,000
Natural gas inventory	-124,955,000	3,676,000	125,042,000
Prepaid expenses and other current assets	542,000	358,000	-1,527,000
Other assets	-517,000	-807,000	-1,105,000
Trade payables	-212,000	-149,000	645,000
Accrued liabilities	-63,709,000	68,106,000	8,927,000
Deferred revenue	596,000	5,468,000	-10,667,000
Other long-term liabilities	-520,000	360,000	381,000
Total	-55,835,000	15,033,000	42,033,000
Proceeds from sales of cushion			$32,600,000

Supplemental_Cash_Flow_Disclos2

Supplemental Cash Flow Disclosures (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Supplemental Cash Flow Disclosures
Interest paid	$30,083	$63,769	$67,408
Taxes paid (received)	50	73	-722
Interest capitalized			2,928
Non-cash investing activities:
Non-cash increase (decrease) in working capital related to property, plant and equipment	2,203	-2,426	-8,605
Non-cash transfer of natural gas inventory to cushion		15,264
Non-cash financing activities:
Non-cash distributions and reinvestments	$19,631	$18,270

Segment_Disclosures_Details

Segment Disclosures (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	item	item	item
Segment Disclosures
Number of reportable segments									1	1	1
Segment disclosures
Write-downs of inventory	($21,600)	($31,700)	($10,500)		($4,600)				($63,800)	($4,600)	($22,281)
Total revenues	-6,867	39,219	10,590	55,377	87,497	25,847	36,863	57,189	98,319	207,396	140,695
Long-lived assets	876,626				1,237,248				876,626	1,237,248
U.S.
Segment disclosures
Long-lived assets	367,920				397,331				367,920	397,331
U.S. \| Inter-entity
Segment disclosures
Net realized revenues									-4,266
U.S. \| Operating segments
Segment disclosures
Net realized revenues									32,265	58,128	73,905
Net unrealized revenues									20,452	142	-37,139
Write-downs of inventory									-22,600	-500	-3,744
Canada
Segment disclosures
Long-lived assets	508,706				839,917				508,706	839,917
Canada \| Inter-entity
Segment disclosures
Net realized revenues									4,266
Canada \| Operating segments
Segment disclosures
Net realized revenues									98,160	162,600	178,945
Net unrealized revenues									11,242	-8,874	-52,735
Write-downs of inventory									($41,200)	($4,100)	($18,537)

Economic_Dependence_Details

Economic Dependence (Details) (Total gross revenue, Other customers)	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Total gross revenue \| Other customers
Economic Dependence
Concentration risk percentage	10.00%	10.00%	10.00%

Quarterly_Financial_Data_Detai

Quarterly Financial Data (Details) (USD $)	3 Months Ended								12 Months Ended
Quarterly Financial Data (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Quarterly Financial Data
Revenue, net	($6,867,000)	$39,219,000	$10,590,000	$55,377,000	$87,497,000	$25,847,000	$36,863,000	$57,189,000	$98,319,000	$207,396,000	$140,695,000
Earnings (loss) before income taxes	-43,010,000	-275,258,000	-36,180,000	-27,864,000	635,000	-19,718,000	-7,797,000	7,667,000	-382,312,000	-19,213,000	-62,543,000
Net earnings (loss) and comprehensive income (loss)	-43,229,000	-259,623,000	-28,832,000	-18,972,000	4,330,000	-13,409,000	-7,845,000	7,967,000	-350,656,000	-8,957,000	-43,601,000
Earnings (loss) per unit	($1.12)	($6.85)	($0.78)	($0.52)	$0.12	($0.37)	($0.22)	$0.23	($9.34)	($0.25)	($0.63)
One-time contract termination payment				26,000,000					26,000,000
Depreciation related to migration of cushion		31,100,000	5,700,000	27,900,000					64,700,000		9,300,000
Write-downs of inventory (Note 15)	21,600,000	31,700,000	10,500,000		4,600,000				63,800,000	4,600,000	22,281,000
Impairment of goodwill		245,600,000							245,604,000
Loss on extinguishment of debt					($36,700,000)					($36,697,000)	($599,000)