Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities
Net margins including noncontrolling interest	$ 23,822	$ 17,585
Adjustments to reconcile net margins to net cash used in operating activities:
Depreciation, amortization, and depletion	46,672	38,903
Amortization of intangible asset	1,831	1,831
Amortization of NRECA Retirement Security Plan prepayment	1,343	1,343
Amortization of debt issuance costs	527	470
Recognition of deferred membership withdrawal income	(2,500)
Capital credit allocations from cooperatives and income from coal mines over refund distributions	(1,199)	(1,703)
Recognition of deferred revenue	(7,500)
Change in restricted cash and investments	(16)	(23)
Changes in operating assets and liabilities:
Accounts receivable	4,195	10,224
Coal inventory	3,394	6,205
Materials and supplies	1,439	(606)
Accounts payable and accrued expenses	(10,732)	(15,729)
Accrued interest	16,775	14,412
Accrued property taxes	(1,053)	(1,492)
Other deferred credits - TEP transmission settlement	(15,521)
Other	(12,656)	(10,197)
Net cash provided by operating activities	48,821	61,223
Investing activities
Purchases of plant	(32,628)	(40,326)
Changes in deferred charges	1,707	(5,171)
Proceeds from other investments	61	313
Net cash used in investing activities	(30,860)	(45,184)
Financing activities
Changes in Member advances	(5,611)	(438)
Payments of long-term debt	(48,502)	(41,247)
Proceeds from issuance of debt		45,000
Increase in short-term borrowings, net	5,580
Retirement of patronage capital	(3,023)	(2,879)
Other	304	(319)
Net cash provided by (used in) financing activities	(51,252)	117
Net increase (decrease) in cash and cash equivalents	(33,291)	16,156
Cash and cash equivalents - beginning	165,893	144,587
Cash and cash equivalents - end	132,602	160,743
Supplemental cash flow information:
Cash paid for interest	23,016	24,647
Supplemental disclosure of noncash investing and financing activities:
Change in plant expenditures included in accounts payable	$ (3,916)	$ (2,369)