Debt: (Tables)

12 Months Ended

Dec. 31, 2016

Debt:

Schedule of maturities for long-term debt and capital lease obligations

		(dollars in thousands)
		2017		2018		2019		2020		2021
FFB	$	183,259	$	151,297	$	156,376	$	171,441	$	176,620
FMBs		1,010		1,010		351,010		1,010		1,010
PCBs(1)		122,620		56,028		37,352		188,226		36,000
CFC		937		984		1,035		391		–
CoBank		2,600		–		–		–		–
		310,426		209,319		545,773		361,068		213,630
Capital Leases		6,435		4,905		5,462		6,082		6,772
Total	$	316,861	$	214,224	$	551,235	$	367,150	$	220,402

(1) In addition to regularly scheduled principal payments on the bonds, this includes amounts that would be due if the standby letters of credit supporting the Series 2009 and Series 2010 bonds were drawn upon and became payable in accordance with their terms, such as would occur if the credit facility the letters of credit were issued under was not renewed or extended at its expiration date. These amounts equal $56 million in 2018, $37 million in 2019 and $152 million in 2020. We anticipate extending these credit facilities before their expiration. The nominal maturities of the Series 2009 and Series 2010 pollution control bonds range from 2030 through 2038.

Schedule of principal amount of long-term debt and the associated unamortized debt issuance costs and debt discounts

	2016				2015
		Principal		Unamortized Debt Issuance Costs and Debt Discounts		Principal		Unamortized Debt Issuance Costs and Debt Discounts
		(dollars in thousands)
FFB	$	4,259,723	$	55,754	$	3,777,540	$	56,851
FMBs		3,058,083		36,717		2,809,093		32,002
PCBs		980,770		8,789		980,770		9,135
CFC		3,347		–		4,238		–
CoBank		2,600		–		3,386		–
	$	8,304,523	$	101,260	$	7,575,027	$	97,988