Certain debt instruments of the Company's subsidiaries, including those discussed later, contain restrictive and financial covenants and cross-default provisions. In order to borrow under the debt agreements, the subsidiary companies must be in compliance with the applicable covenants and certain other conditions, all of which the subsidiaries, as applicable, were in compliance with at December 31, 2019. In the event the subsidiaries do not comply with the applicable covenants and other conditions, alternative sources of funding may need to be pursued.

The following table summarizes the outstanding revolving credit facilities of the Company's subsidiaries:



Company	Facility		Facility Limit			Amount Outstanding at December 31, 2019			Amount Outstanding at December 31, 2018			Letters of Credit at December 31, 2019			Expiration Date
			(In millions)
Montana-Dakota Utilities Co.	Commercial paper/Revolving credit agreement	(a)	$	175.0		$	118.6	(b)	$	48.5		$	—		12/19/24
Cascade Natural Gas Corporation	Revolving credit agreement		$	100.0	(c)	$	64.6		$	53.8		$	2.2	(d)	6/7/24
Intermountain Gas Company	Revolving credit agreement		$	85.0	(e)	$	24.5		$	56.3		$	1.4	(d)	6/7/24
Centennial Energy Holdings, Inc.	Commercial paper/Revolving credit agreement	(f)	$	600.0		$	104.3	(b)	$	289.6	(b)	$	—		12/19/24

The respective commercial paper programs are supported by revolving credit agreements. While the amount of commercial paper outstanding does not reduce available capacity under the respective revolving credit agreements, Montana-Dakota and Centennial do not issue commercial paper in an aggregate amount exceeding the available capacity under their credit agreements. The commercial paper borrowings may vary during the period, largely the result of fluctuations in working capital requirements due to the seasonality of certain operations of the Company's subsidiaries.



	Weighted Average Interest Rate at December 31, 2019		2019		2018
			(In thousands)
Senior Notes due on dates ranging from October 22, 2022 to November 18, 2059	4.45	%	$	1,850,000	$	1,381,000
Commercial paper supported by revolving credit agreements	2.04	%	222,900		338,100
Term Loan Agreement due on September 3, 2032	2.00	%	9,100		209,800
Credit agreements due on June 7, 2024	4.40	%	89,050		110,100
Medium-Term Notes due on dates ranging from September 1, 2020 to March 16, 2029	6.68	%	50,000		50,000
Other notes due on dates ranging from July 15, 2021 to November 30, 2038	4.48	%	29,117		25,229
Less unamortized debt issuance costs			7,010		5,207
Less discount			50		327
Total long-term debt			2,243,107		2,108,695
Less current maturities			16,540		251,854
Net long-term debt			$	2,226,567	$	1,856,841

Montana-Dakota On January 1, 2019, the Company's revolving credit agreement and commercial paper program became Montana-Dakota's revolving credit agreement and commercial paper program as a result of the Holding Company Reorganization. The outstanding balance of the revolving credit agreement was also transferred to Montana-Dakota. All of the related terms and covenants of the credit agreements remained the same. For more information on the reorganization, see Note 1.

On December 19, 2019, Montana-Dakota amended and restated its revolving credit agreement extending the maturity date to December 19, 2024. Montana-Dakota's revolving credit agreement supports its commercial paper program. Commercial paper borrowings under this agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued commercial paper borrowings.

The credit agreement contains customary covenants and provisions, including covenants of Montana-Dakota not to permit, as of the end of any fiscal quarter, the ratio of funded debt to total capitalization (determined on a consolidated basis) to be greater than 65 percent. Other covenants include limitations on the sale of certain assets and on the making of certain loans and investments.

On July 24, 2019, Montana-Dakota entered into a $200.0 million note purchase agreement with maturity dates ranging from October 17, 2039 to November 18, 2059, at a weighted average interest rate of 3.95 percent. The agreement contains customary covenants and provisions, including a covenant of Montana-Dakota not to permit, at any time, the ratio of total debt to total capitalization to be greater than 65 percent.

Cascade On June 7, 2019, Cascade amended its revolving credit agreement to increase the borrowing capacity to $100.0 million and extend the maturity date to June 7, 2024. Any borrowings under the revolving credit agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued borrowings.

The credit agreement contains customary covenants and provisions, including a covenant of Cascade not to permit, at any time, the ratio of total debt to total capitalization to be greater than 65 percent. Other covenants include restrictions on the sale of certain assets, limitations on indebtedness and the making of certain investments.

On June 13, 2019, Cascade issued $75.0 million of senior notes with maturity dates ranging from June 13, 2029 to June 13, 2049, at a weighted average interest rate of 3.93 percent. The agreement contains customary covenants and provisions, including a covenant of Cascade not to permit, at any time, the ratio of total debt to total capitalization to be greater than 65 percent.

Intermountain On June 7, 2019, Intermountain amended its revolving credit agreement to extend the maturity date to June 7, 2024. Any borrowings under the revolving credit agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued borrowings.

The credit agreement contains customary covenants and provisions, including a covenant of Intermountain not to permit, at any time, the ratio of total debt to total capitalization to be greater than 65 percent. Other covenants include restrictions on the sale of certain assets, limitations on indebtedness and the making of certain investments.

On June 13, 2019, Intermountain issued $50.0 million of senior notes with maturity dates ranging from June 13, 2029 to June 13, 2049, at a weighted average interest rate of 3.92 percent. The agreement contains customary covenants and provisions, including a covenant of Intermountain not to permit, at any time, the ratio of total debt to total capitalization to be greater than 65 percent.

Centennial On December 19, 2019, Centennial amended and restated its revolving credit agreement to increase the borrowing capacity to $600.0 million and extend the maturity date to December 19, 2024. Centennial's revolving credit agreement supports its commercial paper program. Commercial paper borrowings under this agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued commercial paper borrowings.

Centennial's revolving credit agreement contains customary covenants and provisions, including a covenant of Centennial, not to permit, as of the end of any fiscal quarter, the ratio of total consolidated debt to total consolidated capitalization to be greater than 65 percent. Other covenants include restricted payments, restrictions on the sale of certain assets, limitations on subsidiary indebtedness, minimum consolidated net worth, limitations on priority debt and the making of certain loans and investments.

On April 4, 2019, Centennial issued $150.0 million of senior notes with maturity dates ranging from April 4, 2029 to April 4, 2034, at a weighted average interest rate of 4.60 percent. The agreement contains customary covenants and provisions, including a covenant of Centennial not to permit, at any time, the ratio of total debt to total capitalization to be greater than 60 percent.

Certain of Centennial's financing agreements contain cross-default provisions. These provisions state that if Centennial or any subsidiary of Centennial fails to make any payment with respect to any indebtedness or contingent obligation, in excess of a specified amount, under any agreement that causes such indebtedness to be due prior to its stated maturity or the contingent obligation to become payable, the applicable agreements will be in default.

WBI Energy Transmission On July 26, 2019, WBI Energy Transmission amended its uncommitted note purchase and private shelf agreement to increase capacity to $300.0 million and extend the issuance period to May 16, 2022. On December 16, 2019, WBI Energy Transmission issued $45.0 million of senior notes under the private shelf agreement with a maturity date of December 16, 2034, at an interest rate of 4.17 percent. WBI Energy Transmission had $170.0 million of notes outstanding at December 31, 2019, which reduced the remaining capacity under this uncommitted private shelf agreement to $130.0 million. This agreement contains customary covenants and provisions, including a covenant of WBI Energy Transmission not to permit, as of the end of any fiscal quarter, the ratio of total debt to total capitalization to be greater than 55 percent. Other covenants include a limitation on priority debt and restrictions on the sale of certain assets and the making of certain investments.