Chugach Electric Association 10-Q 10 May 19 2019 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information	3 Months Ended
	Mar. 31, 2019shares
Document And Entity Information [Abstract]
Entity Registrant Name	CHUGACH ELECTRIC ASSOCIATION INC
Entity Filer Category	Non-accelerated Filer
Entity Central Index Key	0000878004
Amendment Flag	false
Document Type	10-Q
Document Fiscal Period Focus	Q1
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding	0
Entity Emerging Growth Company	false
Entity Small Business	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Utility plant:
Electric plant in service	$ 1,226,720,773	$ 1,216,663,092
Construction work in progress	19,200,960	17,272,307
Total utility plant	1,245,921,733	1,233,935,399
Less accumulated depreciation	(540,007,359)	(529,099,451)
Net utility plant	705,914,374	704,835,948
Other property and investments, at cost:
Nonutility property	76,889	76,889
Operating lease right-of-use assets	934,371	0
Investments in associated organizations	8,155,733	8,570,046
Special funds	1,998,108	1,890,221
Restricted cash equivalents	108,000	108,000
Total other property and investments	11,273,101	10,645,156
Current assets:
Cash and cash equivalents	4,569,216	6,106,995
Special deposits	54,300	54,300
Restricted cash equivalents	1,221,872	1,213,974
Marketable securities	5,218,539	6,316,583
Accounts receivable, net	27,113,373	31,165,249
Materials and supplies	16,326,983	16,223,477
Fuel stock	9,721,782	11,952,086
Prepayments	3,935,723	2,227,117
Other current assets	349,529	241,279
Total current assets	68,511,317	75,501,060
Other non-current assets:
Deferred charges, net	38,120,452	37,668,424
Total other non-current assets	38,120,452	37,668,424
Total assets	823,819,244	828,650,588
Equities and margins:
Memberships	1,753,742	1,748,172
Patronage capital	175,198,092	177,823,597
Other	15,035,783	14,952,925
Total equities and margins	191,987,617	194,524,694
Long-term obligations, excluding current installments:
Bonds payable	374,999,997	398,416,664
Notes payable	33,174,000	33,972,000
Less unamortized debt issuance costs	(2,397,413)	(2,425,247)
Operating lease liabilities	750,388	0
Total long-term obligations	406,526,972	429,963,417
Current liabilities:
Current installments of long-term obligations	26,792,650	26,608,667
Commercial paper	85,000,000	61,000,000
Accounts payable	10,401,055	9,538,749
Consumer deposits	4,498,910	4,845,611
Fuel cost over-recovery	2,409,898	3,388,295
Accrued interest	974,090	5,671,840
Salaries, wages and benefits	8,099,813	7,863,112
Fuel	5,762,034	5,844,856
Other current liabilities	16,856,164	10,085,556
Total current liabilities	160,794,614	134,846,686
Other non-current liabilities:
Deferred compensation	1,451,796	1,359,878
Other liabilities, non-current	630,342	580,841
Deferred liabilities	801,643	764,834
Patronage capital payable	1,931,295	3,393,253
Cost of removal obligation / asset retirement obligation	59,694,965	63,216,985
Total other non-current liabilities	64,510,041	69,315,791
Total liabilities, equities and margins	$ 823,819,244	$ 828,650,588

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Consolidated Statements Of Operations [Abstract]
Operating revenues	$ 55,827,238	$ 56,057,278
Operating expenses:
Fuel	14,738,549	18,487,590
Production	4,858,811	4,423,919
Purchased power	6,893,011	4,082,888
Transmission	2,388,069	1,988,004
Distribution	3,556,619	3,735,960
Consumer accounts	1,713,559	1,865,709
Administrative, general and other	6,325,858	5,544,969
Depreciation and amortization	7,826,369	7,343,077
Total operating expenses	48,300,845	47,472,116
Interest expense:
Long-term debt and other	5,556,614	5,614,735
Charged to construction	(100,958)	(57,363)
Interest expense, net	5,455,656	5,557,372
Net operating margins	2,070,737	3,027,790
Nonoperating margins:
Interest income	169,152	159,583
Allowance for funds used during construction	45,557	23,873
Capital credits, patronage dividends and other	100,131	(83,286)
Total nonoperating margins	314,840	100,170
Assignable margins	$ 2,385,577	$ 3,127,960

Consolidated Statements Of Chan

Consolidated Statements Of Changes In Equities And Margins - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Balance	$ 194,524,694
Assignable margins	2,385,577	$ 3,127,960
Balance	191,987,617	192,432,153
Memberships [Member]
Balance	1,748,172	1,719,154
Memberships and donations received	5,570	5,605
Balance	1,753,742	1,724,759
Other Equities And Margins [Member]
Balance	14,952,925	14,653,253
Unclaimed capital credits retired	(1,577)	(2,570)
Memberships and donations received	84,435	76
Balance	15,035,783	14,650,759
Patronage Capital [Member]
Balance	177,823,597	172,928,887
Assignable margins	2,385,577	3,127,960
Retirement/net transfer of capital credits	5,011,082	212
Balance	$ 175,198,092	$ 176,056,635

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flow - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Assignable margins	$ 2,385,577	$ 3,127,960
Adjustments to reconcile assignable margins to net cash provided by operating activities:
Depreciation and amortization	7,826,369	7,343,077
Amortization and depreciation cleared to operating expenses	1,806,639	1,262,244
Allowance for funds used during construction	(45,557)	(23,873)
Write off of inventory, deferred charges and projects	395,724	26,443
Other	(96,544)	82,710
(Increase) decrease in assets:
Accounts receivable, net	2,283,765	6,416,498
Fuel cost under-recovery	0	211,817
Materials and supplies	(103,950)	(862,658)
Fuel stock	2,230,304	253,645
Prepayments	(1,708,606)	(17,290)
Other assets	(108,250)	(106,967)
Deferred charges	(1,974,444)	(771,655)
Increase (decrease) in liabilities:
Accounts payable	234,512	(766,388)
Consumer deposits	(346,701)	(56,808)
Fuel cost over-recovery	(978,397)	0
Accrued interest	(4,697,750)	(4,950,872)
Salaries, wages and benefits	236,701	339,040
Fuel	(82,822)	(236,196)
Other current liabilities	(311,991)	(272,951)
Deferred liabilities	(15,271)	(815)
Net cash provided by operating activities	6,929,308	10,996,961
Cash flows from investing activities:
Return of capital from investment in associated organizations	414,313	413,897
Investment in special funds	(7,377)	(3,139)
Investment in marketable securities and investments-other	(14,004)	0
Proceeds from the sale of marketable securities	1,200,000	250,556
Extension and replacement of plant	(10,891,794)	(3,963,731)
Net cash used in investing activities	(9,298,862)	(3,302,417)
Cash flows from financing activities:
Payments for debt issue costs	(31,609)	0
Net increase (decrease) in short-term obligations	24,000,000	12,000,000
Repayments of long-term obligations	(24,214,667)	(24,214,667)
Memberships and donations received	88,428	3,111
Retirement of patronage capital and estate payments	(111,082)	(212)
Proceeds from consumer advances for construction	1,108,603	1,078,462
Net cash provided by (used in) financing activities	839,673	(11,133,306)
Net change in cash, cash equivalents, and restricted cash equivalents	(1,529,881)	(3,438,762)
Cash, cash equivalents, and restricted cash equivalents at beginning of period	7,428,969	7,201,759
Cash, cash equivalents, and restricted cash equivalents at end of period	5,899,088	3,762,997
Supplemental disclosure of non-cash investing and financing activities:
Cost of removal obligation	(3,522,020)	577,754
Extension and replacement of plant included in accounts payable	2,518,520	581,314
Patronage capital retired/net transferred and included in other current liabilities	8,361,958	2,000,000
Supplemental disclosure of cash flow information - interest expense paid, net of amounts capitalized	$ 9,867,631	$ 10,380,240

Presentation Of Financial Infor

Presentation Of Financial Information	3 Months Ended
	Mar. 31, 2019
Presentation Of Financial Information [Abstract]
Presentation Of Financial Information	1. PRESENTATION OF FINANCIAL INFORMATION  The accompanying unaudited interim financial statements include the accounts of Chugach Electric Association, Inc. (“Chugach”) and have been prepared in accordance with generally accepted accounting principles for interim financial information. Accordingly, they do not include all of the information and footnotes required by United States of America generally accepted accounting principles (“U.S. GAAP”) for complete financial statements. They should be read in conjunction with Chugach’s audited financial statements for the year ended December 31, 2018, filed as part of Chugach’s annual report on Form 10-K. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. The results of operations for interim periods are not necessarily indicative of the results that may be expected for an entire year or any other period. 

Description Of Business

Description Of Business	3 Months Ended
	Mar. 31, 2019
Description Of Business [Abstract]
Description Of Business	2. DESCRIPTION OF BUSINESS  Chugach is one of the largest electric utilities in Alaska. Chugach is engaged in the generation, transmission and distribution of electricity in the Anchorage and upper Kenai Peninsula areas. Chugach is on an interconnected regional electrical system referred to as the Alaska Railbelt, a 400 -mile-long area stretching from the coastline of the southern Kenai Peninsula to the interior of the state, including Alaska's largest cities, Anchorage and Fairbanks.  Chugach’s retail and wholesale members are the consumers of the electricity sold. Chugach supplies much of the power requirements of the City of Seward (“Seward”), as a wholesale customer. Occasionally, Chugach sells available generation, in excess of its own needs, to Matanuska Electric Association, Inc. (“MEA”), Homer Electric Association, Inc. (“HEA”), Golden Valley Electric Association, Inc. (“GVEA”) and Anchorage Municipal Light & Power (“ML&P”).  Chugach was organized as an Alaska electric cooperative in 1948 and operates on a not ‑for ‑profit basis and, accordingly, seeks only to generate revenues sufficient to pay operating and maintenance costs, the cost of purchased power, capital expenditures, depreciation, and principal and interest on all indebtedness and to provide for reserves. Chugach is subject to the regulatory authority of the Regulatory Commission of Alaska (“RCA”).  Chugach has three Collective Bargaining Agreements (“CBA’s”) with the International Brotherhood of Electrical Workers (“IBEW”), representing approximately 70% of its workforce. Chugach also has an agreement with the Hotel Employees and Restaurant Employees (“HERE”). All three IBEW CBA’s are effective th rough June 30, 2021 . The three CBA’s provide for wage increases in all years and include health and welfare premium cost sharing provisions. The HERE contract is effective through June 30, 2021, and provides for wage, pension contribution, and health and welfare contribution increases in all years.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
Significant Accounting Policies [Abstract]
Significant Accounting Policies	3. SIGNIFICANT ACCOUNTING POLICIES  a. Management Estimates  In preparing the financial statements in conformity with U.S. GAAP, the management of Chugach is required to make estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the balance sheet and revenues and expenses for the reporting period. Estimates include allowance for doubtful accounts, workers’ compensation liability, deferred charges and liabilities, unbilled revenue, estimated useful life of utility plant, cost of removal and asset retirement obligation (“ARO”), and remaining proved Beluga River Unit (“BRU”) reserves. Actual results could differ from those estimates.  b. Regulation  The accounting records of Chugach conform to the Uniform System of Accounts as prescribed by the Federal Energy Regulatory Commission (“FERC”). Chugach meets the criteria, and accordingly, follows the accounting and reporting requirements of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 980, “Topic 980 - Regulated Operations.” FASB ASC 980 provides for the recognition of regulatory assets and liabilities as allowed by regulators for costs or credits that are reflected in current rates or are considered probable of being included in future rates. Chugach’s regulated rates are established to recover all of the specific costs of providing electric service. In each rate filing, rates are set at levels to recover all of the specific allowable costs and those rates are then collected from retail and wholesale customers. The regulatory assets or liabilities are then reduced as the cost or credit is reflected in earnings and our rates.  c. Income Taxes  Chugach is exempt from federal income taxes under the provisions of Section 501(c)(12) of the Internal Revenue Code and for the three month periods ended March 31, 2019 and 2018 was in compliance with that provision.  Chugach applies a more-likely-than-not recognition threshold for all tax uncertainties. FASB ASC 740, “Topic 740 – Income Taxes,” only allows the recognition of those tax benefits that have a greater than 50% likelihood of being sustained upon examination by the taxing authorities. Chugach’s management reviewed Chugach’s tax positions and determined there were no outstanding or retroactive tax positions that were not highly certain of being sustained upon examination by the taxing authorities.  d. Cash, Cash Equivalents, and Restricted Cash Equivalents  The following table provides a reconciliation of cash, cash equivalents, and restricted cash equivalents reported within the Consolidated Balance Sheet that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows.     March 31, 2019 December 31, 2018  Cash and cash equivalents $ 4,569,216 $ 6,106,995  Restricted cash equivalents 1,221,872 1,213,974  Restricted cash equivalents included in other property and investments 108,000 108,000  Total cash, cash equivalents and restricted cash equivalents shown in the consolidated statements of cash flows $ 5,899,088 $ 7,428,969  Restricted cash equivalents include funds on deposit for future workers’ compensation claims.  e. Marketable Securities  Chugach’s marketable securities consist of bond mutual funds, corporate bonds, and certificates of deposit with a maturity less than 12 months, classified as trading securities, reported at fair value with gains and losses in earnings. Interest and dividend income is included in nonoperating margins – interest income, and was $62.9 thousand and $84.7 thousand at March 31, 2019 and 2018, respectively. Net gains and losses on marketable securities are included in nonoperating margins – capital credits, patronage dividends and other, and are summarized as follows:     Three months ended March 31, 2019 Three months ended March 31, 2018  Net gains (losses) recognized during the period on trading securities $ 87,952 $ 79,413  Less: Net gains (losses) recognized during the period on trading securities sold during the period 0 (495)  Unrealized gains (losses) recognized during the reporting period on trading securities still held at the reporting date $ 87,952 $ 79,908  f. Accounts Receivable  Included in accounts receivable are amounts invoiced to ML&P for their proportionate share of current Southcentral Power Project (“SPP”) costs, which amounted to $1. 2 million and $ 1.4 million at March 31, 2019 and December 31, 2018, respectively.  g. Fuel Stock  Fuel Stock is the weighted average cost of fuel injected into Cook Inlet Natural Gas Storage, LLC (“CINGSA”). Chugach’s fuel balance in storage amounted to $9.7 million and $12.0 million at March 31, 2019, and December 31, 2018, respectively.  h. Investments in Associated Organizations Chugach’s investments in associated organizations are considered equity securities without readily determinable fair values, and as such are measured at cost minus impairment, if any. There were no impairments of these investments recognized during the three months ended March 31, 2019 or 2018.

Revenue From Contracts With Cus

Revenue From Contracts With Customers	3 Months Ended
	Mar. 31, 2019
Revenue From Contracts With Customers [Abstract]
Revenue From Contracts With Customers	4. REVENUE FROM CONTRACTS WITH CUSTOMERS  a. Nature of goods and services  The following is a description of the contracts and customer classes from which Chugach generates revenue.  i. Energy Sales  Energy sales revenues are Chugach’s primary source of revenue, representing approximately 97.5% and 95.5% of total operating revenue during the three months ended March 31, 2019 and 2018, respectively. Energy sales revenues are recognized upon delivery of electricity, based on billing rates authorized by the RCA, which are applied to customers’ usage of electricity. Chugach’s rates are established, in part, on test period sales levels that reflect actual operating results. Chugach's tariffs include provisions for the recovery of gas costs according to gas supply contracts and costs associated with the BRU operations, as well as purchased power costs.  Expenses associated with electric services include fuel purchased from others and produced from Chugach’s interest in the BRU, both of which are used to generate electricity, as well as power purchased from others. Chugach is authorized by the RCA to recover fuel and purchased power costs through the fuel and purchased power adjustment process, which is adjusted quarterly to reflect increases and decreases of such costs . The amount of fuel and purchased power revenue recognized is equal to actual fuel and purchased power costs. We recognize differences between projected recoverable fuel and purchased power costs and amounts actually recovered through rates. The fuel cost under/over recovery on our balance sheet represents the net accumulation of any under- or over-collection of fuel and purchased power costs. Fuel cost under-recovery will appear as an asset on our balance sheet and will be collected from our members in subsequent periods. Conversely, fuel cost over-recovery will appear as a liability on our balance sheet and will be refunded to our members in subsequent periods.   Customer Class Nature, timing of satisfaction of performance obligations, and significant payment terms  Retail Retail energy customers can have up to four components of monthly billing included in revenue – energy, fuel and purchased power, demand and customer charge. The energy rate and fuel and purchased power surcharge are applied by kilowatt hour (kWh) usage. The demand charge is applied by kilowatt (kW). The customer charge is a monthly amount applied by meter. Wholesale Classified as firm energy sales. Four components of monthly billing are included in revenue – energy, fuel and purchased power, demand and customer charge. The energy rate and fuel and purchased power surcharge are applied by kWh usage. The demand charge is applied by kW. The customer charge is a monthly amount applied by meter. Economy Classified as non-firm energy sales. Three components of monthly billing are included in revenue – fuel, operations and maintenance, and margin. The actual fuel costs are billed per thousand cubic feet (Mcf) used. The operations and maintenance and margin rates are applied by megawatt hour (MWh) usage.  Payment on energy sales invoices to all customer classes above are due within 15 to 30 days.  Chugach calculates unbilled revenue, for residential and commercial customers, at the end of each month to ensure the recognition of a full month of revenue. Chugach accrued $7,996,257 and $9,176,639 of unbilled retail revenue at March 31, 2019 and 2018, respectively, which is included in accounts receivable on the balance sheet. Revenue derived from wholesale and economy customers is recorded from metered locations on a calendar month basis, so no estimation is required.  The collectability of our energy sales is very high with typically 0.10% written off as bad debt expense, adjusted annually.  There were no costs associated with obtaining any of these contracts, therefore no asset was recognized or recorded associated with obtaining any contract.  ii. Wheeling  Wheeling represented 1.4% and 3.6% of our revenue during the three months ended March 31 , 2019 and 2018, respectively. Wheeling was recorded through the wheeling of energy across Chugach’s transmission lines at rates set by utility tariff and approved by the RCA . The rates are applied to MWh of energy wheeled. The collectability of wheeling is very high, with no adjustment required.  iii. Other Miscellaneous Services  Other miscellaneous services consist of various agreements including dispatch service and gas transfer agreements, pole rentals and microwave bandwidth. Revenue from these agreements is billed monthly and represented 1.1% and 0.9% of our total operating revenue during the three months ended March 31, 2019 and 2018, respectively. The revenue recognized from these agreements is recorded as the service is provided over a period of time. The collectability of these agreements is very high, with no adjustment required.  b. Disaggregation of Revenue  The table below details the revenue recognized by customer class and disaggregates base revenue from fuel and purchased power revenue recognized in the Consolidated Statement of Operations for the first quarter of 2019 and 2018 (in millions).     Base Rate Sales Revenue Fuel and Purchased Power Revenue Total Revenue  2019 2018 % Variance 2019 2018 % Variance 2019 2018 % Variance  Retail $ 33.1 $ 32.3 2.5 % $ 19.9 $ 19.9 0.0 % $ 53.0 $ 52.2 1.5 %  Wholesale $ 0.5 $ 0.5 0.0 % $ 0.9 $ 0.8 12.5 % $ 1.4 $ 1.3 7.7 %  Economy $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 %  Total Energy Sales $ 33.6 $ 32.8 2.4 % $ 20.8 $ 20.7 0.5 % $ 54.4 $ 53.5 1.7 %  Wheeling $ 0.0 $ 0.0 0.0 % $ 0.8 $ 2.0 (60.0 %) $ 0.8 $ 2.0 (60.0 %)  Gas Sales $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 %  Other $ 0.6 $ 0.5 20.0 % $ 0.0 $ 0.0 0.0 % $ 0.6 $ 0.5 20.0 %  Total Miscellaneous $ 0.6 $ 0.5 20.0 % $ 0.8 $ 2.0 (60.0 %) $ 1.4 $ 2.5 (44.0 %)  Total Revenue $ 34.2 $ 33.3 2.7 % $ 21.6 $ 22.7 (4.8 %) $ 55.8 $ 56.0 (0.4 %)  c. Contract Balances  There were no contract assets at March 31, 2019, or at December 31, 2018. The table below provides information about contract receivables and contract liabilities.     March 31, 2019 December 31, 2018  Contract receivables, included in accounts receivable $ 24,944,577 $ 27,179,031  Contract liabilities 3,919,328 5,196,426  Contract receivables represent amounts receivable from retail, wholesale, economy and wheeling.  Contract liabilities consist of credit balances and fuel cost over-recovery. Credit balances are reported as consumer deposits and represent the prepaid accounts of retail customers and are recognized in revenue as the customer uses electric service. Fuel cost over-recovery represents the over-collection of fuel and purchased power costs through the fuel and purchased power adjustment process, which will be refunded to customers through lower rates in the following quarter.  Significant changes in contract liabilities balances are as follows:     March 31, 2019 December 31, 2018  Contract liabilities at beginning of period $ 5,196,426 $ 1,581,481  Cash received, excluding amounts recognized as revenue during the period 3,393,362 5,196,426  Revenue recognized that was included in the contract liability balance at the beginning of the period (4,670,460) (1,581,481)  Contract liabilities at end of period $ 3,919,328 $ 5,196,426  d. Transaction Price Allocated to Remaining Performance Obligations  The table below includes estimated revenue to be recognized during the remainder of 2019 related to performance obligations that are unsatisfied (or partially unsatisfied) at March 31, 2019.     2019  Credit balances $ 1,509,430  Fuel cost over-recovery 2,409,898  Credit balances are primarily associated with Chugach’s LevelPay program. The program calculates the monthly amount to be collected from customers annually. It is anticipated the balance will be recognized in revenue within the following year as customers consume electricity.  Chugach’s fuel cost over- and under- recovery are adjusted quarterly, therefore, amounts over or under collected will be collected or refunded in the following quarter.

Regulatory Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2019
Regulatory Matters [Abstract]
Regulatory Matters	5. REGULATORY MATTERS  Simplified Rate Filing  Chugach is a participant in the Simplified Rate Filing (“SRF”) process for adjustments to base demand and energy rates for Chugach retail customers and wholesale customer, Seward. SRF is an expedited base rate adjustment process available to electric cooperatives in the State of Alaska, with filings made either on a quarterly or semi-annual basis. Chugach is a participant on a quarterly filing schedule basis. Chugach is required to submit filings to the RCA for approval before any rate changes can be implemented. While there is no limitation on decreases, base rate increases under SRF are limited to 8% in a 12-month period and 20% in a 36-month period.  Chugach submitted quarterly SRF filings which resulted in a system demand and energy rate increase of 2.7% effective November 1, 2018; an increase of 0.7% effective February 1, 2019; and an increase of 0.8% effective May 1, 2019.  Operation and Regulation of the Alaska Railbelt Electric and Transmission System  In June 2016, the RCA opened a docket to “evaluate the reliability and security standards and practices of Alaska Electric Utilities.” In 2017, Chugach and several other Alaska Railbelt utilities entered into a contract with GDS Associates, Inc. (“GDS”). GDS’s role was to facilitate discussion between all six Alaska Railbelt utilities and various stakeholders with an end goal of submitting to the RCA a Railbelt Reliability Council (“RRC”), including a governance structure, that will be responsible for adoption and enforcement of uniform reliability standards and integrated transmission resource planning and evaluation on transition to a single regional load balancing area. GDS presented to the RCA during two technical conferences in January and March of 2018. Chugach and the other utilities provided GDS’s final recommendation of the RRC to the RCA in May 2018. During fourth quarter of 2018, the utilities reviewed and adapted the memorandum of understanding with GDS (“GDS MOU”) with the RCA. The utilities are currently in discussions with non-utility stakeholders to include their input in the RRC formation process. In parallel, the utilities and an affiliate of A merican Transmission Company ( “ ATC ” ) are in discussions regarding the formation of a transmission-only utility. ATC, GVEA, HEA, ML&P, and Seward Electric System filed with the RCA for a Railbelt-wide Transco Certificate of Public Convenience (“CPCN”) on February 25, 2019. Chugach and MEA were not a party to this filing. Currently our organization’s primary focus is on filing with the RCA for the transfer of the ML&P CPCN to Chugach, and we were unable to complete our due diligence on the Transco filing prior to the filing date. In order to preserve our options, Chugach will intervene in the filing and intends on completing its due diligence of the Transco filing in the second quarter of 2019 to protect its interest in ML&P’s transmission assets provided for in the Asset Purchase Agreement . Chugach cannot determine the materiality of any effect on its results of operations, financial condition, and cash flows until a business model and plan are adopted. The RCA initiated an order on March 15, 2019 requesting comments on proposed legislative language which would authorize the RCA to designate or develop an Electric Reliability Organization (“ERO”). Chugach submitted comments on this proposed legislative language seeking to delay adoption until the RRC Governance Board can be formed.  In June 2016, in response to Docket I-16-002, Railbelt Utility Information Technology and Operations Technology, leadership began meeting to discuss Railbelt Cybersecurity. The Railbelt Utilities Managers group designated the Cybersecurity Working Group to review industry standards and provide a statement of work to develop Railbelt Cybersecurity Standards. On June 21, 2018, Chugach posted a Request for Proposal to hire a consultant to write the standards. A final draft was presented to the Railbelt Utility Managers on February 15, 2019 .  ML&P Acquisition  In December 2017, the Mayor of Anchorage, Alaska, announced plans to place a proposition on the April 3, 2018 municipal ballot allowing the voters to authorize the sale of ML&P to Chugach. The proposition was approved by Anchorage voters 65.08% to 34.92% per the certified election results. Chugach and the Municipality of Anchorage (“MOA”) negotiated final sales agreements and associated documents. The sale of ML&P was approved by the Anchorage Assembly on December 4, 2018 and the Chugach Board of Directors gave its final approval on December 19, 2018. The agreements and associated documents were executed on December 28, 2018. Pursuant to these agreements and associated documents, on April 1, 2019, Chugach submitted the Joint Request for Necessary Approvals for Acquisition of Anchorage Municipal Light and Power, and the Petition for Approvals Needed to Acquire Anchorage Municipal Light and Power and Application to Amend Certificate of Public Convenience and Necessity No. 8 to the RCA. The RCA accepted the filing as complete on April 18, 2019, and the procedural conference was held on April 22, 2019. On May 8, 2019, the RCA issued an order indicating that a final order in the case will be issued by November 19, 2019. In addition, the RCA granted the petitions to intervene filed by MEA; Providence Health and Services (“Providence”); GVEA; the Federal Executive Agencies (“FEA”); and HEA / Alaska Electric and Energy Cooperative, Inc. For more information, see “ITEM 1 – FINANCIAL STATEMENTS – Note 10 – ML&P ACQUISITION.” 

Debt

Debt	3 Months Ended
	Mar. 31, 2019
Debt [Abstract]
Debt	6. DEBT  Lines of Credit  Chugach maintains a $50.0 million line of credit with National Rural Utilities Cooperative Finance Corporation (“NRUCFC”). Chugach did not utilize this line of credit in the three months ended March 31, 2019. In addition, Chugach did not utilize this line of credit during 2018 and had no outstanding balance at December 31, 2018. The borrowing rate is calculated using the total rate per annum and may be fixed by NRUCFC. The borrowing rate was 4.00 % at March 31, 2019, and 3.75% at December 31, 2018. The NRUCFC Revolving Line Of Credit Agreement requires that Chugach, for each 12 -month period, for a period of at least five consecutive days, pay down the entire outstanding principal balance. The NRUCFC line of credit was renewed September 29, 2017, and expires September 29, 2022 . This line of credit is immediately available for unconditional borrowing.  Commercial Paper  On June 13, 2016 , Chugach entered into a $150.0 million senior unsecured credit facility (“The Credit Agreement”) which is used to back Chugach’s commercial paper program. The pricing includes an all-in drawn spread of one month London Interbank Offered Rate (“LIBOR”) plus 90.0 basis points, along with a 10.0 basis points facility fee (based on an A/A2/A unsecured debt rating) . The Credit Agreement will expire on June 13, 2021 . The participating banks include NRUCFC, KeyBank National Association, Bank of America, N.A., and CoBank, ACB. The commercial paper can be repriced between one day and 270 days.  Chugach expects to continue issuing commercial paper in 2019, as needed. Chugach had $85.0 million and $61.0 million of commercial paper outstanding at March 31, 2019, and December 31, 2018, respectively.  The following table provides information regarding average commercial paper balances outstanding for the quarter ended March 31, 2019, and 2018 (dollars in millions), as well as corresponding weighted average interest rates:    2019 2018  Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate  $ 61.8 2.78 % $ 45.1 1.93 %  Term Loans  Chugach has a term loan facility with CoBank. Loans made under this facility are evidenced by the 2016 CoBank Note, which is governed by the Amended and Restated Master Loan Agreement dated June 30, 2016 (“CoBank Loan Agreement”), and secured by the Second Amended and Restated Indenture of Trust (“Indenture”). At March 31, 2019, Chugach had $ 36.4 million outstanding with CoBank.  Debt Issuance Costs  The following table outlines debt issuance costs associated with long-term obligations, excluding current installments, at March 31, 2019.    Long-term Obligations Unamortized Debt Issuance Costs  2011 Series A Bonds $ 178,999,997 $ 1,067,463  2012 Series A Bonds 162,000,000 918,122  2017 Series A Bonds 34,000,000 186,281  2016 CoBank Note 33,174,000 193,938  2019 Financing Costs 0 31,609  $ 408,173,997 $ 2,397,413  The following table outlines debt issuance costs associated with long-term obligations, excluding current installments, at December 31, 2018.     Long-term Obligations Unamortized Debt Issuance Costs  2011 Series A Bonds $ 189,666,664 $ 1,096,801  2012 Series A Bonds 172,750,000 938,028  2017 Series A Bonds 36,000,000 188,904  2016 CoBank Note 33,972,000 201,514  $ 432,388,664 $ 2,425,247 

Recent Accounting Pronouncement

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2019
Recent Accounting Pronouncements [Abstract]
Recent Accounting Pronouncements	7. RECENT ACCOUNTING PRONOUNCEMENTS  Issued, and adopted at March 31, 2019:  ASC Update 2016-02 “ Leases (Topic 842)” and Related Updates  In February of 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” ASU 2016-02 amends guidance related to the recognition, measurement, presentation and disclosure of leases for lessors and lessees. Pursuant to the new standard, lessees will be required to identify all leases, including those embedded in contracts, classify leases as finance or operating, recognize all leases on the balance sheet and record corresponding right-of-use assets and lease liabilities. The update requires the recognition of lease assets and liabilities for those leases currently classified as operating leases while also refining the definition of a lease. Operating leases will reflect lease expense on a straight-line basis, while finance leases will result in the separate presentation of interest expense on the lease liability and amortization expense of the right-of-use asset.  In January 2018, the FASB issued ASU 2018-01, “Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842.” ASU 2018-01 amends ASU 2016-02 to provide an optional transition practical expedient allowing entities to not evaluate under Topic 842 existing or expired land easements that were not previously accounted for as leases under the current lease guidance in Topic 840.  In December 2018, the FASB issued ASU 2018-20, “Leases (Topic 842): Narrow-Scope Improvements for Lessors.” ASU 2018-20 amends ASU 2016-02 to address lessor stakeholders concerns regarding the following issues: sales taxes and other similar taxes collected from lessees, certain lessor costs, and recognition of variable payments from contracts with lease and nonlease components.  Topic 842 requires a modified retrospective transition, with the cumulative effect of transition, including initial recognition by lessees of lease assets and liabilities for existing operating leases, as of either the effective date, or the beginning of the earliest period presented. Under the effective date method, the entity’s comparative reporting period is unchanged. Comparative reporting periods are presented in accordance with Topic 840, while periods subsequent to the effective date are presented in accordance with Topic 842. Chugach elected to use the effective date method.  The standard includes certain practical expedients intended to ease the burden of adoption on preparers. Chugach elected each of the following practical expedients:  1) Package of Practical expedients (all or nothing) - An entity may elect not to reassess: a) whether expired or existing contracts contain leases under the new definition of a lease, b) lease classification for expired or existing leases and c) whether previously capitalized initial direct costs would qualify for capitalization under Topic 842. 2) Use of hindsight - An entity may use hindsight in determining the lease term, and in assessing the likelihood that a lease purchase option will be exercised. 3) Land easements - An entity may elect not to reassess whether land easements meet the definition of a lease if they were not accounted for as leases prior to adoption of Topic 842 until they expire, unless they are modified on or after the effective date.  A lessee may elect not to separate the non-lease components of a contract from the lease component to which they relate. This means that the components will be treated as a single lease component. The lessee elects this practical expedient by class of underlying asset – for example: office equipment, automobiles, office space. Chugach elected this practical expedient for all classes of underlying assets.  Chugach elected not to recognize right-of-use assets and lease liabilities that arise from short-term leases (those with a term of less than twelve months) for any class of underlying asset. These updates are effective for fiscal years beginning after December 15, 2018, including the interim periods within those years, with early adoption permitted. Chugach began application of ASU 2016-02 and related updates on January 1, 2019. Adoption did not have a material effect on our results of operations, financial position, and cash flows. See “ Note 8 – LEASES .”  Issued, not yet adopted:  ASC Update 2016-13 “ Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments ”  In June 2016, the FASB issued ASU 2016-13, “Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” ASU 2016-13 revised the criteria for the measurement, recognition, and reporting of credit losses on financial instruments to be recognized when expected. This update is effective for fiscal years beginning after December 15, 2019, including the interim periods within those years, with early adoption permitted for fiscal years beginning after December 15, 2018, including interim periods within those years. Chugach will begin application of ASU 2016-13 on January 1, 2020. Adoption is not expected to have a material effect on its results of operations, financial position, and cash flows.  ASC Update 2018-13 “ Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement”  In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement.” ASU 2018-13 which changes the fair value measurement disclosure requirements of ASC 820. This update is effective for all entities for fiscal years beginning after December 15, 2019, including interim periods therein. Early adoption is permitted for any eliminated or modified disclosures upon issuance of this ASU. Chugach will begin application of ASU 2018-13 on January 1, 2020. Adoption is not expected to have a material effect on its results of operations, financial position, and cash flows.  ASC Update 2018-14 “ Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans”  In August 2018, the FASB issued ASU 2018-14, “Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20): Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans.” ASU 2018-14 Modifies ASC 715-20 to improve disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. The ASU is effective for fiscal years ending after December 15, 2020, for public companies. Early adoption is permitted. Chugach will begin application of ASU 2018-14 on January 1, 2021. Adoption is not expected to have a material effect on its results of operations, financial position, and cash flows.  ASC Update 2018-15 “ Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force)”  In August 2018, the FASB issued ASU 2018-15, “Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract.” ASU 2018-15 aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The ASU is effective for public business entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. Early adoption is permitted. Chugach will begin application of ASU 2018-15 on January 1, 2020. Adoption is not expected to have a material effect on its results of operations, financial position, and cash flows. 

Leases

Leases	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Leases	8. LEASES  Effective January 1, 2019, Chugach began application of Accounting Standards Codification 842, Leases (Topic 842). Adoption of the new standard requires recognition of leases on the balance sheet. Chugach has no financing leases and several operating leases, most of which are various land easements. Chugach identified two operating leases as right-of-use assets for a building and office equipment, with remaining lease terms of one to five years and a weighted average lease term of 4.74 years. Chugach’s operating lease assets are presented as operating lease right-of-use assets on the consolidated balance sheet. The current portion of operating lease liabilities is included in current installments of long-term obligations and the long-term portion is presented as operating lease liabilities on the consolidated balance sheet. A discount rate of 4.6% was used in calculating the right-to-use assets and lease liabilities.  Adoption had no impact on our consolidated statements of operations. The recognition of the right-of-use asset and operating lease liability represents a non-cash investing and financing activity. Total operating lease expense for the three months ended March 31, 2019, was $228,392 , primarily associated with land easements and helicopter services .  Supplemental cash flow information associated with leases:     Three months ended March 31, 2019  Cash paid for amounts included in the measurement of liabilities:  Operating cash flows from operating leases $ 54,000  Right-of-use assets obtained in exchange for lease obligations:  Operating leases $ 934,371  Supplemental balance sheet information associated with leases at March 31 were:     2019  Operating lease right-of-use assets $ 934,371  Operating lease liabilities $ 750,388  Current installments of lease liabilities 183,983  Total operating lease liabilities $ 934,371  Maturities associated with lease liabilities:     March 31, 2019  2019 $ 163,890  2020 216,840  2021 216,000  2022 216,000  2023 216,000  Total lease payments 1,028,730  Less imputed interest 94,359  Present value of lease liabilities $ 934,371  Chugach entered into the Power Purchase Agreement with Fire Island Wind, LLC, (“FIW”) on June 21, 2011. The Fire Island Wind contract contains a lease because the agreement identifies an asset (the wind farm is explicitly specified in the agreement and FIW does not have substantive substitution rights) and Chugach controls the use of the asset (it takes 100% of the output and, to the extent there is wind, can control how and when the wind farm produces power directly using its SCADA system). However, due to the exclusively variable nature of the payments related to Fire Island Wind, no new assets or liabilities have been added to the balance sheet, no changes were made to the cash flow statement, and the variable payments are still classified as purchased power expense on the statement of operations . The amount of the variable payments included in purchased power for the three months ended March 31, 2019, was $1,242,432 .

Fair Values Of Assets And Liabi

Fair Values Of Assets And Liabilities	3 Months Ended
	Mar. 31, 2019
Fair Values Of Assets And Liabilities [Abstract]
Fair Values Of Assets And Liabilities	9. FAIR VALUES OF ASSETS AND LIABILITIES  Fair Value Hierarchy  In accordance with FASB ASC 820, Chugach groups its financial assets and liabilities measured at fair value in three levels, based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value. These levels are:  Level 1 – Valuation is based upon quoted prices for identical instruments traded in active exchange markets, such as the New York Stock Exchange. Level 1 also includes United States Treasury and federal agency securities, which are traded by dealers or brokers in active markets. Valuations are obtained from readily available pricing sources for market transactions involving identical assets or liabilities.  Level 2 – Valuation is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant assumptions are observable in the market.  Level 3 – Valuation is generated from model-based techniques that use significant assumptions not observable in the market. These unobservable assumptions reflect Chugach’s estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques include use of option pricing models, discounted cash flow models and similar techniques.  The table below presents the balance of Chugach’s marketable securities measured at fair value on a recurring basis at March 31, 2019, and December 31, 201 8. Chugach’s bond mutual funds are measured using quoted prices in active markets. Chugach had no other assets or liabilities measured at fair value on a recurring basis at March 31, 201 9, or at December 31, 201 8.      March 31, 2019 Total Level 1 Level 2 Level 3  Bond mutual funds $ 5,218,539 $ 5,218,539 $ 0 $ 0   December 31, 2018 Total Level 1 Level 2 Level 3  Bond mutual funds $ 6,316,583 $ 6,316,583 $ 0 $ 0  Fair Value of Financial Instruments  Fair value estimates are dependent upon subjective assumptions and involve significant uncertainties resulting in variability in estimates with changes in assumptions. The fair value of cash and cash equivalents, accounts receivable and payable, and other short-term monetary assets and liabilities approximate carrying value due to their short-term nature.  The estimated fair values (in thousands) of long-term obligations included in the financial statements at March 31, 2019, are as follows:       Carrying Value Fair Value Level 2  Long-term obligations (including current installments) $ 434,783 $ 447,278 

ML&P Acquisition

ML&P Acquisition	3 Months Ended
	Mar. 31, 2019
Acquisition [Abstract]
ML&P Acquisition	10. ML&P Acquisition  In December 2017, the Mayor of Anchorage, Alaska, announced plans to place a proposition on the April 3, 2018 municipal ballot allowing the voters to authorize the sale of ML&P to Chugach. The proposition was approved by Anchorage voters 65.08% to 34.92% per the certified election results. Chugach and the MOA negotiated final sales agreements and associated documents. The sale of ML&P was approved by the Anchorage Assembly on December 4, 2018 and the Chugach Board of Directors gave its final approval on December 19, 2018.  On December 28, 2018, Chugach entered into the Asset Purchase and Sale Agreement (“APA”) with the MOA to acquire substantially all of the assets, and certain specified liabilities of ML&P, subject to approval by the RCA. On December 28, 2018, Chugach also entered into an Eklutna Power Purchase Agreement, a Payment in Lieu of Taxes Agreement and a BRU Fuel Agreement (“Ancillary Agreements”) with the MOA.  During the first week of April 2019, pursuant to the APA, Chugach and the MOA jointly submitted applications to amend their respective CPCNs to permit Chugach to provide electric service in ML&P’s legacy service territory. The RCA accepted the filing as complete on April 18, 2019, and a procedural conference was held on April 22, 2019. On May 8, 2019, the RCA issued an order indicating that a final order in the case will be issued by November 19, 2019. In addition, the RCA granted the petitions to intervene filed by MEA; Providence Health and Services (“Providence”); GVEA; the Federal Executive Agencies (“FEA”); and HEA / Alaska Electric and Energy Cooperative, Inc. Additionally, Chugach and MOA will cooperate to obtain an order from the RCA approving the Ancillary Agreements and allowing Chugach to recover the costs associated with the transaction. Following RCA approval, a closing date will be scheduled for the transaction within 120 days. Upon closing, Chugach will transfer the purchase price of $767.8 million less the estimated accrued leave liability and the estimated net book value of designated excluded assets. The APA also includes terms for post-closing purchase price adjustments. The Eklutna Power Purchase Agreement, which will be effective upon closing, provides for the purchase of all or a portion of ML&P’s share of generation from the Eklutna Hydroelectric Project by Chugach from MOA for a period of 35 years at specified fixed prices each year.  The Payment in Lieu of Taxes Agreement (“PILT Agreement”), which will be effective upon closing, provides for Chugach to make annual payments in lieu of taxes to the MOA for a period of 50 years based on current millage rates and the adjusted book value of property for ML&Ps service territory as in existence at the closing as adjusted each year. The PILT Agreement also provides that until December 31, 2033, Chugach shall only collect amounts associated with those annual PILT payments from retail customers in the legacy ML&P territory. Thereafter, the annual PILT payments shall be collected from all Chugach retail customers.  The BRU Fuel Agreement, which will be effective upon closing, provides that through December 31, 2033, Chugach will use gas attributable to production in the portion of the Beluga River Unit acquired from MOA to serve retail customers of Chugach within the legacy ML&P territory at a specified gas transfer price and will use any excess gas to serve other customers of Chugach at the same specified gas transfer price. 

Environmental Matters

Environmental Matters	3 Months Ended
	Mar. 31, 2019
Environmental Matters [Abstract]
Environmental Matters	11. ENVIRONMENTAL MATTERS  Chugach includes costs associated with environmental compliance in both our operating and capital budgets. We accrue for costs associated with environmental remediation obligations when those costs are probable and reasonably estimated. We do not anticipate that environmental related expenditures will have a material effect on our results of operations or financial condition. We cannot, however, predict the nature, extent or cost of new laws or regulations relating to environmental matters.  The three utility owners of the Eklutna Hydro Project (Chugach, ML&P, and MEA) are obligated by a 1991 Fish & Wildlife Agreement to develop and implement measures to protect, mitigate, and enhance the fish and wildlife impacted by the project (PME program). The program is to be approved by the Governor of Alaska with completion of the program no later than October of 2032, 35 years after its purchase. The owners initiated a required consultation process with key government agencies and interest ed parties in March 2019. The a greement requires equal consideration of; 1) efficient and economical power production, 2) energy conservation, 3) protection, mitigation of damage to, and enhancement of fish and wildlife, 4) protection of recreation opportunities, 5) municipal water supplies, 6) preservation of other aspects of environmental quality, 7) other beneficial public uses, 9) and requirement of State law. The hydro project and municipal water system currently utilize 100% of the water inflows.  The Clean Air Act and Environmental Protection Agency (“EPA”) regulations under the Clean Air Act establish ambient air quality standards and limit the emission of many air pollutants. New Clean Air Act regulations impacting electric utilities may result from future events or new regulatory programs. An Executive Order promoting energy independence and economic growth was issued on March 28, 2017, by the President instructing the EPA to review the Clean Power Plan (“CPP”). On August 21, 2018 the EPA proposed the Affordable Clean Energy (“ACE”) rule which would establish emission guidelines for states to develop plans to address GHG emissions from existing coal-fired power plants. The ACE rule would replace the 2015 CPP, which EPA has proposed to repeal because it exceeded EPA authority. The CPP was stayed by the U.S. Supreme Court and has never gone into effect. The comment period for the proposed ACE rule has closed and the EPA is currently reviewing and responding to the comments received. When the final rule is promulgated it is certain to face legal challenge. The proposed ACE rule regulation, in its current form, is not expected to have a material effect on Chugach’s financial condition, results of operations, or cash flows. While Chugach cannot predict the implementation of any additional new law or regulation, or the limitations thereof, it is possible that new laws or regulations could increase capital and operating costs. Chugach has obtained or applied for all Clean Air Act permits currently required for the operation of generating facilities.  Chugach is subject to numerous other environmental statutes including the Clean Water Act, the Resource Conservation and Recovery Act, the Toxic Substances Control Act, the Endangered Species Act, and the Comprehensive Environmental Response, Compensation and Liability Act and to the regulations implementing these statutes. Chugach does not believe that compliance with these statutes and regulations to date has had a material impact on its financial condition, results of operation or cash flows. However, the implementation of any additional new law or regulation, or the limitations thereof, or changes in or new interpretations of laws or regulations could result in significant additional capital or operating expenses. Chugach monitors proposed new regulations and existing regulation changes through industry associations and professional organizations. 

Commitments And Contingencies

Commitments And Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments And Contingencies [Abstract]
Commitments And Contingencies	12. COMMITMENTS AND CONTINGENCIES  Contingencies  Chugach is a participant in various legal actions, rate disputes, personnel matters and claims both for and against Chugach’s interests. Management believes the outcome of any such matters will not materially impact Chugach’s financial condition, results of operations or liquidity. Chugach establishes reserves when a particular contingency is probable and calculable. Chugach has not accrued for any contingency at March 31, 2019, as it does not consider any contingency to be probable nor calculable. Chugach faces contingencies that are reasonably possible to occur; however, they cannot currently be estimated.  Concentrations  Approximately 70% of our employees are members of the IBEW. Chugach has three CBA’s with the IBEW. We also have a CBA with the HERE. All three IBEW CBA’s and the HERE CBA have been renewed through June 30, 20 21 .  Commitments  Fuel Supply Contracts  Chugach has fuel supply contracts with various producers at market terms. Chugach entered into a gas contract with Hilcorp effective January 1, 2015 , to provide gas through March 31, 2018 (the “Hilcorp Agreement”). After two amendments to the Hilcorp Agreement, Chugach’s needs are filled 100% through March 31, 2023 . The total amount of gas under this agreement is estimated to be 60 Bcf. All of the production is expected to come from Cook Inlet, Alaska. The terms of the Hilcorp Agreement require Chugach to manage the natural gas transportation over the connecting pipeline systems. Chugach has gas transportation agreements with ENSTAR and Harvest Pipeline.  BRU Operations  Chugach and other owners, ML&P and Hilcorp, are operating under an existing Joint Operating Agreement. Hilcorp is the operator for BRU. The owners are considering updating the existing Joint Operating Agreement to better match the new owners’ interests.  Patronage Capital  Pursuant to agreements reached with HEA and MEA, patronage capital allocated or retired to HEA or MEA is classified as patronage capital payable on Chugach’s Balance Sheet. In March 2019, our Board authorized capital credit retirements in the amount of $4.9 million. At March 31, 2019, patronage capital payable to MEA and HEA was $ 6.1 million and $3.9 million, respectively. At December 31, 2018, patronage capital payable to MEA and HEA was $ 1.5 million and $3.9 million, respectively.  Legal Proceedings  Chugach has certain litigation matters and pending claims that arise in the ordinary course of Chugach’s business. In the opinion of management, none of these matters, individually or in the aggregate, is or are likely to have a material adverse effect on Chugach’s results of operations, financial condition or cash flows.

Significant Accounting Polici_2

Significant Accounting Policies (Policy)	3 Months Ended
	Mar. 31, 2019
Significant Accounting Policies [Abstract]
Management Estimates	a. Management Estimates  In preparing the financial statements in conformity with U.S. GAAP, the management of Chugach is required to make estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the balance sheet and revenues and expenses for the reporting period. Estimates include allowance for doubtful accounts, workers’ compensation liability, deferred charges and liabilities, unbilled revenue, estimated useful life of utility plant, cost of removal and asset retirement obligation (“ARO”), and remaining proved Beluga River Unit (“BRU”) reserves. Actual results could differ from those estimates.
Regulation	b. Regulation  The accounting records of Chugach conform to the Uniform System of Accounts as prescribed by the Federal Energy Regulatory Commission (“FERC”). Chugach meets the criteria, and accordingly, follows the accounting and reporting requirements of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 980, “Topic 980 - Regulated Operations.” FASB ASC 980 provides for the recognition of regulatory assets and liabilities as allowed by regulators for costs or credits that are reflected in current rates or are considered probable of being included in future rates. Chugach’s regulated rates are established to recover all of the specific costs of providing electric service. In each rate filing, rates are set at levels to recover all of the specific allowable costs and those rates are then collected from retail and wholesale customers. The regulatory assets or liabilities are then reduced as the cost or credit is reflected in earnings and our rates.
Income Taxes	c. Income Taxes  Chugach is exempt from federal income taxes under the provisions of Section 501(c)(12) of the Internal Revenue Code and for the three month periods ended March 31, 2019 and 2018 was in compliance with that provision.  Chugach applies a more-likely-than-not recognition threshold for all tax uncertainties. FASB ASC 740, “Topic 740 – Income Taxes,” only allows the recognition of those tax benefits that have a greater than 50% likelihood of being sustained upon examination by the taxing authorities. Chugach’s management reviewed Chugach’s tax positions and determined there were no outstanding or retroactive tax positions that were not highly certain of being sustained upon examination by the taxing authorities.
Cash, Cash Equivalents And Restricted Cash Equivalents	d. Cash, Cash Equivalents, and Restricted Cash Equivalents  The following table provides a reconciliation of cash, cash equivalents, and restricted cash equivalents reported within the Consolidated Balance Sheet that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows.     March 31, 2019 December 31, 2018  Cash and cash equivalents $ 4,569,216 $ 6,106,995  Restricted cash equivalents 1,221,872 1,213,974  Restricted cash equivalents included in other property and investments 108,000 108,000  Total cash, cash equivalents and restricted cash equivalents shown in the consolidated statements of cash flows $ 5,899,088 $ 7,428,969  Restricted cash equivalents include funds on deposit for future workers’ compensation claims.
Marketable Securities	e. Marketable Securities  Chugach’s marketable securities consist of bond mutual funds, corporate bonds, and certificates of deposit with a maturity less than 12 months, classified as trading securities, reported at fair value with gains and losses in earnings. Interest and dividend income is included in nonoperating margins – interest income, and was $62.9 thousand and $84.7 thousand at March 31, 2019 and 2018, respectively. Net gains and losses on marketable securities are included in nonoperating margins – capital credits, patronage dividends and other, and are summarized as follows:     Three months ended March 31, 2019 Three months ended March 31, 2018  Net gains (losses) recognized during the period on trading securities $ 87,952 $ 79,413  Less: Net gains (losses) recognized during the period on trading securities sold during the period 0 (495)  Unrealized gains (losses) recognized during the reporting period on trading securities still held at the reporting date $ 87,952 $ 79,908 
Accounts Receivable	f. Accounts Receivable  Included in accounts receivable are amounts invoiced to ML&P for their proportionate share of current Southcentral Power Project (“SPP”) costs, which amounted to $1. 2 million and $ 1.4 million at March 31, 2019 and December 31, 2018, respectively.
Fuel Stock	g. Fuel Stock  Fuel Stock is the weighted average cost of fuel injected into Cook Inlet Natural Gas Storage, LLC (“CINGSA”). Chugach’s fuel balance in storage amounted to $9.7 million and $12.0 million at March 31, 2019, and December 31, 2018, respectively. 
Investments In Associated Organizations	h. Investments in Associated Organizations Chugach’s investments in associated organizations are considered equity securities without readily determinable fair values, and as such are measured at cost minus impairment, if any. There were no impairments of these investments recognized during the three months ended March 31, 2019 or 2018.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2019
Significant Accounting Policies [Abstract]
Reconciliation Of Cash, Cash Equivalents, And Restricted Cash Equivalents	   March 31, 2019 December 31, 2018  Cash and cash equivalents $ 4,569,216 $ 6,106,995  Restricted cash equivalents 1,221,872 1,213,974  Restricted cash equivalents included in other property and investments 108,000 108,000  Total cash, cash equivalents and restricted cash equivalents shown in the consolidated statements of cash flows $ 5,899,088 $ 7,428,969 
Schedule Of Gains And Losses On Trading Securities	   Three months ended March 31, 2019 Three months ended March 31, 2018  Net gains (losses) recognized during the period on trading securities $ 87,952 $ 79,413  Less: Net gains (losses) recognized during the period on trading securities sold during the period 0 (495)  Unrealized gains (losses) recognized during the reporting period on trading securities still held at the reporting date $ 87,952 $ 79,908 

Revenue From Contracts With C_2

Revenue From Contracts With Customers (Tables)	3 Months Ended
	Mar. 31, 2019
Revenue From Contracts With Customers [Abstract]
Schedule Of Disaggregation Of Revenue	   Base Rate Sales Revenue Fuel and Purchased Power Revenue Total Revenue  2019 2018 % Variance 2019 2018 % Variance 2019 2018 % Variance  Retail $ 33.1 $ 32.3 2.5 % $ 19.9 $ 19.9 0.0 % $ 53.0 $ 52.2 1.5 %  Wholesale $ 0.5 $ 0.5 0.0 % $ 0.9 $ 0.8 12.5 % $ 1.4 $ 1.3 7.7 %  Economy $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 %  Total Energy Sales $ 33.6 $ 32.8 2.4 % $ 20.8 $ 20.7 0.5 % $ 54.4 $ 53.5 1.7 %  Wheeling $ 0.0 $ 0.0 0.0 % $ 0.8 $ 2.0 (60.0 %) $ 0.8 $ 2.0 (60.0 %)  Gas Sales $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 % $ 0.0 $ 0.0 0.0 %  Other $ 0.6 $ 0.5 20.0 % $ 0.0 $ 0.0 0.0 % $ 0.6 $ 0.5 20.0 %  Total Miscellaneous $ 0.6 $ 0.5 20.0 % $ 0.8 $ 2.0 (60.0 %) $ 1.4 $ 2.5 (44.0 %)  Total Revenue $ 34.2 $ 33.3 2.7 % $ 21.6 $ 22.7 (4.8 %) $ 55.8 $ 56.0 (0.4 %) 
Schedule Of Contract Balances	   March 31, 2019 December 31, 2018  Contract receivables, included in accounts receivable $ 24,944,577 $ 27,179,031  Contract liabilities 3,919,328 5,196,426 
Schedule Of Changes In Contract Balances	   March 31, 2019 December 31, 2018  Contract liabilities at beginning of period $ 5,196,426 $ 1,581,481  Cash received, excluding amounts recognized as revenue during the period 3,393,362 5,196,426  Revenue recognized that was included in the contract liability balance at the beginning of the period (4,670,460) (1,581,481)  Contract liabilities at end of period $ 3,919,328 $ 5,196,426 
Schedule Of Remaining Performance Obligation	   2019  Credit balances $ 1,509,430  Fuel cost over-recovery 2,409,898 

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2019
Debt [Abstract]
Schedule Of Average Commercial Paper Balances Outstanding And Weighted Average Interest Rates	   2019 2018  Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate  $ 61.8 2.78 % $ 45.1 1.93 % 
Schedule Of Debt Issuance Costs Associated With Long-Term Obligations	The following table outlines debt issuance costs associated with long-term obligations, excluding current installments, at March 31, 2019.    Long-term Obligations Unamortized Debt Issuance Costs  2011 Series A Bonds $ 178,999,997 $ 1,067,463  2012 Series A Bonds 162,000,000 918,122  2017 Series A Bonds 34,000,000 186,281  2016 CoBank Note 33,174,000 193,938  2019 Financing Costs 0 31,609  $ 408,173,997 $ 2,397,413  The following table outlines debt issuance costs associated with long-term obligations, excluding current installments, at December 31, 2018.     Long-term Obligations Unamortized Debt Issuance Costs  2011 Series A Bonds $ 189,666,664 $ 1,096,801  2012 Series A Bonds 172,750,000 938,028  2017 Series A Bonds 36,000,000 188,904  2016 CoBank Note 33,972,000 201,514  $ 432,388,664 $ 2,425,247 

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Supplemental Cash Flow Information	   Three months ended March 31, 2019  Cash paid for amounts included in the measurement of liabilities:  Operating cash flows from operating leases $ 54,000  Right-of-use assets obtained in exchange for lease obligations:  Operating leases $ 934,371 
Supplemental Balance Sheet Information	   2019  Operating lease right-of-use assets $ 934,371  Operating lease liabilities $ 750,388  Current installments of lease liabilities 183,983  Total operating lease liabilities $ 934,371 
Maturities Associated With Lease Liabilities	   March 31, 2019  2019 $ 163,890  2020 216,840  2021 216,000  2022 216,000  2023 216,000  Total lease payments 1,028,730  Less imputed interest 94,359  Present value of lease liabilities $ 934,371 

Fair Values Of Assets And Lia_2

Fair Values Of Assets And Liabilities (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Values Of Assets And Liabilities [Abstract]
Schedule Of Marketable Securities	   March 31, 2019 Total Level 1 Level 2 Level 3  Bond mutual funds $ 5,218,539 $ 5,218,539 $ 0 $ 0   December 31, 2018 Total Level 1 Level 2 Level 3  Bond mutual funds $ 6,316,583 $ 6,316,583 $ 0 $ 0 
Schedule Of Estimated Fair Value Of Long-Term Obligations Included In Financial Statements	   Carrying Value Fair Value Level 2  Long-term obligations (including current installments) $ 434,783 $ 447,278 

Description Of Business (Detail

Description Of Business (Details)	3 Months Ended
	Mar. 31, 2019miagreement
Description Of Business [Line Items]
Electrification area | mi	400
Hotel Employees And Restaurant Employees [Member]
Description Of Business [Line Items]
Number of collective bargaining agreements	1
Expiration date of collective bargaining agreements	Jun. 30, 2021
International Brotherhood of Electrical Workers [Member]
Description Of Business [Line Items]
Number of collective bargaining agreements	3
Percentage of employees belonging to unions	70.00%
Expiration date of collective bargaining agreements	Jun. 30, 2021

Significant Accounting Polici_4

Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Interest income	$ 62,900	$ 84,700
Accounts receivable, net	27,113,373		$ 31,165,249
Fuel stock	9,721,782		11,952,086
Impairment on investments	0	$ 0
ML&P For Fuel And South Central Power Project Costs [Member]
Significant Accounting Policies [Line Items]
Accounts receivable, net	$ 1,200,000		$ 1,400,000

Significant Accounting Polici_5

Significant Accounting Policies (Reconciliation Of Cash, Cash Equivalents, And Restricted Cash Equivalents) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Significant Accounting Policies [Abstract]
Cash and cash equivalents	$ 4,569,216	$ 6,106,995
Restricted cash equivalents	1,221,872	1,213,974
Restricted cash equivalents included in other property and investments	108,000	108,000
Total cash, cash equivalents and restricted cash equivalents shown in the consolidated statements of cash flows	$ 5,899,088	$ 7,428,969	$ 3,762,997	$ 7,201,759

Significant Accounting Polici_6

Significant Accounting Policies (Schedule Of Gains And Losses On Trading Securities) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Significant Accounting Policies [Abstract]
Net gains (losses) recognized during the period on trading securities	$ 87,952	$ 79,413
Less: Net gains (losses) recognized during the period on trading securities sold during the period	0	(495)
Unrealized gains (losses) recognized during the reporting period on trading securities still held at the reporting date	$ 87,952	$ 79,908

Revenue From Contracts With C_3

Revenue From Contracts With Customers (Narrative) (Details)	3 Months Ended
	Mar. 31, 2019USD ($)item	Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)
Disaggregation of Revenue [Line Items]
Contract assets | $	$ 0		$ 0
Contract cost | $	0
Energy Sales [Member]
Disaggregation of Revenue [Line Items]
Unbilled revenue | $	$ 7,996,257	$ 9,176,639
Energy Sales [Member] | Minimum [Member]
Disaggregation of Revenue [Line Items]
Payment terms	15 days
Energy Sales [Member] | Maximum [Member]
Disaggregation of Revenue [Line Items]
Payment terms	30 days
Energy Sales [Member] | Sales Revenue [Member] | Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	97.50%	95.50%
Energy Sales [Member] | Sales Revenue [Member] | Credit Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	0.10%
Retail [Member]
Disaggregation of Revenue [Line Items]
Number of components of monthly billing | item	4
Wholesale [Member]
Disaggregation of Revenue [Line Items]
Number of components of monthly billing | item	4
Economy [Member]
Disaggregation of Revenue [Line Items]
Number of components of monthly billing | item	3
Wheeling [Member] | Sales Revenue [Member] | Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	1.40%	3.60%
Other Miscellaneous [Member] | Sales Revenue [Member] | Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	1.10%	0.90%

Revenue From Contracts With C_4

Revenue From Contracts With Customers (Schedule Of Disaggregation Of Revenue) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 55,827,238	$ 56,057,278
Variance percent	(0.40%)
Energy Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 54,400,000	53,500,000
Variance percent	1.70%
Retail [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 53,000,000	52,200,000
Variance percent	1.50%
Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 1,400,000	1,300,000
Variance percent	7.70%
Economy [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Miscellaneous Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 1,400,000	2,500,000
Variance percent	(44.00%)
Wheeling [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 800,000	2,000,000
Variance percent	(60.00%)
Gas Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Other Miscellaneous [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 600,000	500,000
Variance percent	20.00%
Base Rate Sales Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 34,200,000	33,300,000
Variance percent	2.70%
Base Rate Sales Revenue [Member] | Energy Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 33,600,000	32,800,000
Variance percent	2.40%
Base Rate Sales Revenue [Member] | Retail [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 33,100,000	32,300,000
Variance percent	2.50%
Base Rate Sales Revenue [Member] | Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 500,000	500,000
Variance percent	0.00%
Base Rate Sales Revenue [Member] | Economy [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Base Rate Sales Revenue [Member] | Miscellaneous Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 600,000	500,000
Variance percent	20.00%
Base Rate Sales Revenue [Member] | Wheeling [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Base Rate Sales Revenue [Member] | Gas Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Base Rate Sales Revenue [Member] | Other Miscellaneous [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 600,000	500,000
Variance percent	20.00%
Fuel And Purchased Power Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 21,600,000	22,700,000
Variance percent	(4.80%)
Fuel And Purchased Power Revenue [Member] | Energy Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 20,800,000	20,700,000
Variance percent	0.50%
Fuel And Purchased Power Revenue [Member] | Retail [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 19,900,000	19,900,000
Variance percent	0.00%
Fuel And Purchased Power Revenue [Member] | Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 900,000	800,000
Variance percent	12.50%
Fuel And Purchased Power Revenue [Member] | Economy [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Fuel And Purchased Power Revenue [Member] | Miscellaneous Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 800,000	2,000,000
Variance percent	(60.00%)
Fuel And Purchased Power Revenue [Member] | Wheeling [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 800,000	2,000,000
Variance percent	(60.00%)
Fuel And Purchased Power Revenue [Member] | Gas Sales [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	0
Variance percent	0.00%
Fuel And Purchased Power Revenue [Member] | Other Miscellaneous [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0
Variance percent	0.00%

Revenue From Contracts With C_5

Revenue From Contracts With Customers (Schedule Of Contract Balances) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue From Contracts With Customers [Abstract]
Contract receivables, included in accounts receivable	$ 24,944,577	$ 27,179,031
Contract liabilities	$ 3,919,328	$ 5,196,426	$ 1,581,481

Revenue From Contracts With C_6

Revenue From Contracts With Customers (Schedule Of Changes In Contract Balances) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Revenue From Contracts With Customers [Abstract]
Contract liabilities at beginning of period	$ 5,196,426	$ 1,581,481
Cash received, excluding amounts recognized as revenue during the period	3,393,362	5,196,426
Revenue recognized that was included in the contract liability balance at the beginning of the period	(4,670,460)	(1,581,481)
Contract liabilities at end of period	$ 3,919,328	$ 5,196,426

Revenue From Contracts With C_7

Revenue From Contracts With Customers (Schedule Of Remaining Performance Obligation) (Details)	Mar. 31, 2019USD ($)
Credit Balances [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 1,509,430
Fuel Cost Over-Recovery [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 2,409,898

Regulatory Matters (Details)

Regulatory Matters (Details) - entity	May 09, 2019	Apr. 30, 2019	Mar. 31, 2019	Jan. 31, 2019	Dec. 31, 2018
Other Commitments [Line Items]
Approved percentage increase (decrease) in rates				2.70%
Number of utilities participating in RRC			6
Percentage of voters in favor of acquisition					65.08%
Percentage of voters against acquisition					34.92%
Rate Increases Within 12 Months [Member]
Other Commitments [Line Items]
Rate increase threshold			8.00%
Rate Increases Within 36 Months [Member]
Other Commitments [Line Items]
Rate increase threshold			20.00%
Forecast [Member]
Other Commitments [Line Items]
Approved percentage increase (decrease) in rates		0.70%
Subsequent Event [Member]
Other Commitments [Line Items]
Approved percentage increase (decrease) in rates	0.80%
ML&P Acquisition [Member]
Other Commitments [Line Items]
Percentage of voters in favor of acquisition					65.08%
Percentage of voters against acquisition					34.92%

Debt (Narrative) (Details)

Debt (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Commercial paper	$ 85,000,000	$ 61,000,000
Balance outstanding	$ 408,173,997	432,388,664
Commercial Paper [Member] | Minimum [Member]
Debt Instrument [Line Items]
Commercial paper repricing term	1 day
Commercial Paper [Member] | Maximum [Member]
Debt Instrument [Line Items]
Commercial paper repricing term	270 days
Revolving Line Of Credit [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 50,000,000
Line of credit, outstanding balance		$ 0
Line of credit, borrowing rate description	The borrowing rate is calculated using the total rate per annum and may be fixed by NRUCFC.
Line of credit, borrowing rate	4.00%	3.75%
Period of time the line of credit needs to be paid down for five consecutive days	12 months
Number of consecutive days debt needs to be paid down to $0 during a twelve month period	5 days
Line of credit, expiration date	Sep. 29, 2022
Credit Agreement [Member] | Unsecured Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 150,000,000
Line of credit, borrowing rate description	one month London Interbank Offered Rate ("LIBOR") plus 90.0 basis points, along with a 10.0 basis points facility fee (based on an A/A2/A unsecured debt rating)
Line of credit, commencement date	Jun. 13, 2016
Line of credit, expiration date	Jun. 13, 2021
Facility fee	0.10%
Credit Agreement [Member] | Unsecured Credit Facility [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Variable rate	0.90%
2011 Series A Bonds [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Balance outstanding	$ 178,999,997	$ 189,666,664
2012 Series A Bonds [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Balance outstanding	162,000,000	172,750,000
2016 CoBank Note [Member]
Debt Instrument [Line Items]
Balance outstanding	36,400,000
2016 CoBank Note [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Balance outstanding	33,174,000	33,972,000
2017 Series A Bonds [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Balance outstanding	$ 34,000,000	$ 36,000,000

Debt (Schedule Of Average Comme

Debt (Schedule Of Average Commercial Paper Balances Outstanding And Weighted Average Interest Rates) (Details) - Commercial Paper [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Short-term Debt [Line Items]
Average Balance	$ 61.8	$ 45.1
Weighted Average Interest Rate	2.78%	1.93%

Debt (Schedule Of Debt Issuance

Debt (Schedule Of Debt Issuance Costs Associated With Long-Term Obligations) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Obligations	$ 408,173,997	$ 432,388,664
Less unamortized debt issuance costs	2,397,413	2,425,247
2011 Series A Bonds [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Obligations	178,999,997	189,666,664
Less unamortized debt issuance costs	1,067,463	1,096,801
2012 Series A Bonds [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Obligations	162,000,000	172,750,000
Less unamortized debt issuance costs	918,122	938,028
2017 Series A Bonds [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Obligations	34,000,000	36,000,000
Less unamortized debt issuance costs	186,281	188,904
2016 CoBank Note [Member]
Debt Instrument [Line Items]
Long-term Obligations	36,400,000
2016 CoBank Note [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Obligations	33,174,000	33,972,000
Less unamortized debt issuance costs	193,938	$ 201,514
2019 Financing Costs [Member]
Debt Instrument [Line Items]
Long-term Obligations	0
Less unamortized debt issuance costs	$ 31,609

Leases (Narrative) (Details)

Leases (Narrative) (Details)	3 Months Ended
	Mar. 31, 2019USD ($)agreement
Lessee, Lease, Description [Line Items]
Number of leases | agreement	2
Weighted average remaining lease term	4 years 8 months 27 days
Discount rate	4.60%
Operating lease cost	$ 228,392
Percent of control of leased asset	100.00%
Variable payments	$ 1,242,432
Maximum [Member]
Lessee, Lease, Description [Line Items]
Lease term	5 years
Minimum [Member]
Lessee, Lease, Description [Line Items]
Lease term	1 year
Accounting Standards Update 2016-02 [Member]
Lessee, Lease, Description [Line Items]
Impact of adoption	$ 0

Leases (Supplemental Cash Flow

Leases (Supplemental Cash Flow Information) (Details)	3 Months Ended
	Mar. 31, 2019USD ($)
Leases [Abstract]
Operating cash flows from operating leases	$ 54,000
Operating leases	$ 934,371

Leases (Supplemental Balance Sh

Leases (Supplemental Balance Sheet Information) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease right-of-use assets	$ 934,371	$ 0
Operating lease liabilities	750,388	$ 0
Current installments of lease liabilities	183,983
Total operating lease liabilities	$ 934,371

Leases (Maturities Associated W

Leases (Maturities Associated With Lease Liabilities) (Details)	Mar. 31, 2019USD ($)
Leases [Abstract]
2019	$ 163,890
2020	216,840
2021	216,000
2022	216,000
2023	216,000
Total lease payments	1,028,730
Less imputed interest	94,359
Present value of lease liabilities	$ 934,371

Fair Values Of Assets And Lia_3

Fair Values Of Assets And Liabilities (Narrative) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, liabilities	$ 0	$ 0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, liabilities	0	0
Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, assets	0	0
Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, assets	$ 0	$ 0

Fair Values Of Assets And Lia_4

Fair Values Of Assets And Liabilities (Schedule Of Marketable Securities) (Details) - Bond Mutual Funds [Member] - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 5,218,539	$ 6,316,583
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	5,218,539	6,316,583
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 0	$ 0

Fair Values Of Assets And Lia_5

Fair Values Of Assets And Liabilities (Schedule Of Estimated Fair Value Of Long-Term Obligations Included In Financial Statements) (Details) $ in Thousands	Mar. 31, 2019USD ($)
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term obligations (including current installments)	$ 434,783
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term obligations (including current installments)	$ 447,278

ML&P Acquisition (Details)

ML&P Acquisition (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Percentage of voters in favor of acquisition		65.08%
Percentage of voters against acquisition		34.92%
Eklutna Power Purchase Agreement [Member]
Business Acquisition [Line Items]
Term of purchase commitment	35 years
ML&P Acquisition [Member]
Business Acquisition [Line Items]
Percentage of voters in favor of acquisition		65.08%
Percentage of voters against acquisition		34.92%
Term to set closing date after approval	120 days
Cash consideration	$ 767.8
Payment in lieu of taxes, agreement period	50 years

Environmental Matters (Details)

Environmental Matters (Details)	3 Months Ended
	Mar. 31, 2019
Environmental Matters [Abstract]
Term to complete environmental program	35 years
Percentage of water inflows utilized	100.00%

Commitments And Contingencies (

Commitments And Contingencies (Narrative) (Details)	3 Months Ended
	Mar. 31, 2019USD ($)agreementMcf	Dec. 31, 2018USD ($)
Other Commitments [Line Items]
Contingency accruals	$ 0
Patronage capital, capital credit retirements authorized	4,900,000
Matanuska Electric Association, Inc. [Member]
Other Commitments [Line Items]
Patronage capital payable, current	6,100,000
Patronage capital payable		$ 1,500,000
Homer Electric Association, Inc. [Member]
Other Commitments [Line Items]
Patronage capital payable	$ 3,900,000	$ 3,900,000
Hilcorp Alaska - Cook Inlet [Member]
Other Commitments [Line Items]
Commencement date of long term contract for purchase of gas supply	Jan. 1, 2015
Expiration date of long term contract for purchase of gas supply	Mar. 31, 2018
Estimated amount of gas under contract | Mcf	60,000,000
Percentage Of Met Natural Gas Needs	100.00%
Number of contract extensions | agreement	2
Initial extension date of long term contract for purchase of gas supply	Mar. 31, 2023
International Brotherhood of Electrical Workers [Member]
Other Commitments [Line Items]
Percentage of employees belonging to unions	70.00%
Number of collective bargaining agreements | agreement	3
Expiration date of collective bargaining agreements	Jun. 30, 2021
Hotel Employees And Restaurant Employees [Member]
Other Commitments [Line Items]
Number of collective bargaining agreements | agreement	1
Expiration date of collective bargaining agreements	Jun. 30, 2021