DEBT AND FINANCING ARRANGEMENTS (Tables)

9 Months Ended

Sep. 30, 2018

Details on Long Term Debt

Details on long-term debt at September 30, 2018, September 30, 2017 and December 31, 2017 are shown below:

($ millions)	September 30,				December 31,
	2018		2017		2017
Unitil Corporation:
6.33% Senior Notes, Due May 1, 2022	$	20.0	$	20.0	$	20.0
3.70% Senior Notes, Due August 1, 2026		30.0		30.0		30.0
Unitil Energy First Mortgage Bonds:
5.24% Senior Secured Notes, Due March 2, 2020		10.0		15.0		15.0
8.49% Senior Secured Notes, Due October 14, 2024		7.5		9.0		7.5
6.96% Senior Secured Notes, Due September 1, 2028		20.0		20.0		20.0
8.00% Senior Secured Notes, Due May 1, 2031		15.0		15.0		15.0
6.32% Senior Secured Notes, Due September 15, 2036		15.0		15.0		15.0
Fitchburg:
6.75% Senior Notes, Due November 30, 2023		7.6		9.5		7.6
6.79% Senior Notes, Due October 15, 2025		10.0		10.0		10.0
3.52% Senior Notes, Due November 1, 2027		10.0		—		10.0
7.37% Notes, Due January 15, 2029		12.0		12.0		12.0
5.90% Notes, Due December 15, 2030		15.0		15.0		15.0
7.98% Notes, Due June 1, 2031		14.0		14.0		14.0
4.32% Senior Notes, Due November 1, 2047		15.0		—		15.0
Northern Utilities:
6.95% Senior Notes, Due December 3, 2018		10.0		20.0		10.0
5.29% Senior Notes, Due March 2, 2020		16.6		25.0		25.0
3.52% Senior Notes, Due November 1, 2027		20.0		—		20.0
7.72% Senior Notes, Due December 3, 2038		50.0		50.0		50.0
4.42% Senior Notes, Due October 15, 2044		50.0		50.0		50.0
4.32% Senior Notes, Due November 1, 2047		30.0		—		30.0
Granite State Senior Notes:
7.15% Senior Notes, Due December 15, 2018		3.3		6.7		3.3
3.72% Senior Notes, Due November 1, 2027		15.0		—		15.0
Total Long-Term Debt		396.0		336.2		409.4
Less: Unamortized Debt Issuance Costs		3.1		2.8		3.3
Total Long-Term Debt, net of Unamortized Debt Issuance Costs		392.9		333.4		406.1
Less: Current Portion		31.8		29.8		29.8
Total Long-term Debt, Less Current Portion	$	361.1	$	303.6	$	376.3

Fair Value of Long Term Debt

($ millions)	September 30,				December 31,
	2018		2017		2017
Estimated Fair Value of Long-Term Debt	$	418.7	$	383.0	$	457.1

Borrowing Limits Amounts Outstanding and Amounts Available under Credit Facility

The following table details the borrowing limits, amounts outstanding and amounts available under the Credit Facility as of September 30, 2018, September 30, 2017 and December 31, 2017:

	Credit Facility ($ millions)
	September 30,				December 31,
	2018		2017		2017
Limit	$	120.0	$	120.0	$	120.0
Short-Term Borrowings Outstanding		69.1		111.9		38.3
Letters of Credit Outstanding		—		1.1		—
Available	$	50.9	$	7.0	$	81.7