CONDENSED CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT (Unaudited) (Parenthetical) In Thousands, unless otherwise specified			9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Amortizing Secured Note, due December 20, 2021 [Member]	Sep. 30, 2014 Amortizing Secured Note, due May 19, 2028 [Member]	Sep. 30, 2014 Amortizing Secured Note, due August 25, 2030 [Member]	Sep. 30, 2014 Amortizing Secured Note, due September 19, 2031 [Member]	Sep. 30, 2014 State Revolving Trust Note, due December 31, 2022 [Member]	Sep. 30, 2014 State Revolving Trust Note, due May 1, 2025 [Member]	Sep. 30, 2014 State Revolving Trust Note, due March 1, 2026 [Member]	Sep. 30, 2014 State Revolving Trust Note, due January 25, 2027 [Member]	Sep. 30, 2014 State Revolving Trust Note, due December 1, 2026 [Member]	Sep. 30, 2014 State Revolving Trust Bond, due August 1, 2021 [Member]	Sep. 30, 2014 0% State Revolving Trust Bond, due August 1, 2021 [Member]	Sep. 30, 2014 State Revolving Trust Note, due July 1, 2028 [Member]	Sep. 30, 2014 State Revolving Trust Note, due January 1, 2028 [Member]	Sep. 30, 2014 State Revolving Trust Note, due August 1, 2031 [Member]	Sep. 30, 2014 Amortizing Secured Note, due April 20, 2029 [Member]	Sep. 30, 2014 Amortizing Secured Note, due January 20, 2030 [Member]	Sep. 30, 2014 Amortizing Secured Note, due January 20, 2030 [Member]	Sep. 30, 2014 State Revolving Trust Note, due July 1, 2031 [Member]	Sep. 30, 2014 State Revolving Trust Note, due November 30, 2030 [Member]	Sep. 30, 2014 First Mortgage Bonds - Series X [Member]	Sep. 30, 2014 First Mortgage Bonds - Series Y [Member]	Sep. 30, 2014 First Mortgage Bonds - Series Z [Member]	Sep. 30, 2014 First Mortgage Bonds - Series AA [Member]	Sep. 30, 2014 First Mortgage Bonds - Series BB [Member]	Sep. 30, 2014 First Mortgage Bonds - Series CC [Member]	Sep. 30, 2014 First Mortgage Bonds - Series EE [Member]	Sep. 30, 2014 First Mortgage Bonds - Series FF [Member]	Sep. 30, 2014 First Mortgage Bonds - Series GG [Member]	Sep. 30, 2014 First Mortgage Bonds - Series HH [Member]	Sep. 30, 2014 First Mortgage Bonds - Series II [Member]	Sep. 30, 2014 First Mortgage Bonds - Series JJ [Member]	Sep. 30, 2014 First Mortgage Bonds - Series NN [Member]	Sep. 30, 2014 First Mortgage Bonds - Series LL [Member]	Sep. 30, 2014 First Mortgage Bonds - Series KK [Member]	Sep. 30, 2014 First Mortgage Bonds - Series MM [Member]	Sep. 30, 2014 First Mortgage Bonds - Series OO [Member]	Sep. 30, 2014 First Mortgage Bonds - Series PP [Member]	Sep. 30, 2014 First Mortgage Bonds - Series QQ [Member]	Sep. 30, 2014 First Mortgage Bonds - Series RR [Member]	Sep. 30, 2014 First Mortgage Bonds - Series SS [Member]	Sep. 30, 2014 First Mortgage Bonds - Series TT [Member]	Sep. 30, 2014 First Mortgage Bonds - Series UU [Member]	Sep. 30, 2014 Convertible Preferred Stock $7.00 Series [Member]	Dec. 31, 2013 Convertible Preferred Stock $7.00 Series [Member]	Sep. 30, 2014 Convertible Preferred Stock $8.00 Series [Member]	Dec. 31, 2013 Convertible Preferred Stock $8.00 Series [Member]	Sep. 30, 2014 Nonredeemable Preferred Stock $7.00 Series [Member]	Dec. 31, 2013 Nonredeemable Preferred Stock $7.00 Series [Member]	Sep. 30, 2014 Nonredeemable Preferred Stock $4.75 Series [Member]	Dec. 31, 2013 Nonredeemable Preferred Stock $4.75 Series [Member]
Common Stock, Shares Authorized	40,000	40,000
Common Stock, Shares Outstanding	16,107	15,963
Preferred Stock, Shares Authorized	130	130
Preferred Stock, Shares Outstanding	24	28																																											10	14	3	3	1	1	10	10
Due date of debt			Dec. 20, 2021	May 19, 2028	Aug. 25, 2030	Sep. 19, 2031	Dec. 31, 2022	May 01, 2025	Mar. 01, 2026	Jan. 25, 2027	Dec. 01, 2026	Aug. 01, 2021	Aug. 01, 2021	Jul. 01, 2028	Jan. 01, 2028	Aug. 01, 2031	Apr. 20, 2029	Jan. 20, 2030	Jan. 20, 2030	Jul. 01, 2031	Nov. 30, 2030	Sep. 01, 2018	Sep. 01, 2018	Sep. 01, 2019	Sep. 01, 2019	Sep. 01, 2021	Sep. 01, 2021	Aug. 01, 2023	Aug. 01, 2024	Aug. 01, 2026	Aug. 01, 2026	Aug. 01, 2024	Aug. 01, 2027	Aug. 01, 2030	Aug. 01, 2028	Aug. 01, 2028	Aug. 01, 2030	Aug. 01, 2031	Aug. 01, 2031	Oct. 01, 2023	Oct. 01, 2038	Oct. 01, 2047	Aug. 01, 2032	Aug. 01, 2032
Interest rate			8.05%	6.25%	6.44%	6.46%	4.22%	3.60%	3.30%	3.49%	4.03%		0.00%	3.64%	3.64%	3.45%	6.59%	7.05%	5.69%	3.75%	3.75%	0.00%		0.00%		0.00%		0.00%		0.00%		0.00%				0.00%	0.00%	0.00%		5.00%	3.80%	4.25%	0.00%
Interest rate - minimum												4.00%											4.25%		5.25%		4.00%		3.00%		4.00%		3.40%	3.00%	5.00%				2.00%					3.00%
Interest rate - maximum												5.00%											4.63%		5.75%		5.00%		5.50%		5.00%		5.00%	4.375%	5.50%				5.00%					3.25%