Debt

Certain debt instruments of the Company and its subsidiaries, including those discussed later, contain restrictive covenants and cross-default provisions. In order to borrow under the respective credit agreements, the Company and its subsidiaries must be in compliance with the applicable covenants and certain other conditions, all of which the Company and its subsidiaries, as applicable, were in compliance with at December 31, 2012. In the event the Company and its 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 credit facilities of the Company and its subsidiaries:



Company	Facility		Facility Limit			Amount Outstanding at December 31, 2012			Amount Outstanding at December 31, 2011			Letters of Credit at December 31, 2012			Expiration Date
			(In millions)
MDU Resources Group, Inc.	Commercial paper/Revolving credit agreement	(a)	$	125.0		$	76.0	(b)	$	—	(b)	$	—		10/4/17
Cascade Natural Gas Corporation	Revolving credit agreement		$	50.0	(c)	$	2.0		$	—		$	—		12/27/13
Intermountain Gas Company	Revolving credit agreement		$	65.0	(d)	$	26.2		$	8.1		$	—		8/11/13
Centennial Energy Holdings, Inc.	Commercial paper/Revolving credit agreement	(e)	$	500.0		$	217.0	(b)	$	—	(b)	$	20.2	(f)	6/8/17

(a) The $125 million commercial paper program is supported by a revolving credit agreement with various banks totaling $125 million (provisions allow for increased borrowings, at the option of the Company on stated conditions, up to a maximum of $150 million). There were no amounts outstanding under the credit agreement.

(b) Amount outstanding under commercial paper program.

(d) Certain provisions allow for increased borrowings, up to a maximum of $80 million.

(e) The $500 million commercial paper program is supported by a revolving credit agreement with various banks totaling $500 million (provisions allow for increased borrowings, at the option of Centennial on stated conditions, up to a maximum of $650 million). There were no amounts outstanding under the credit agreement.

(f) The outstanding letters of credit, as discussed in Note 19, reduce amounts available under the credit agreement.

The Company's and Centennial's 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, the Company and Centennial do not issue commercial paper in an aggregate amount exceeding the available capacity under their credit agreements.

The following includes information related to the preceding table.

Short-term borrowings

Cascade Natural Gas Corporation The weighted average interest rate for borrowings outstanding at December 31, 2012, was 3.3 percent.

Cascade's 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. Cascade's credit agreement also contains cross-default provisions. These provisions state that if Cascade 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, Cascade will be in default under the credit agreement. Certain of Cascade's financing agreements and Cascade's practices limit the amount of subsidiary indebtedness.

Intermountain Gas Company The weighted average interest rate for borrowings outstanding at December 31, 2012, was 2.3 percent. These borrowings were classified as short-term borrowings because the revolving credit agreement expires within one year. The borrowings outstanding as of December 31, 2011, were classified as long-term debt as they were intended to be refinanced on a long-term basis through continued borrowings.

The credit agreement contains customary covenants and provisions, including covenants of Intermountain 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.

Intermountain's credit agreement contains cross-default provisions. These provisions state that if (A) Intermountain fails to make any payment with respect to any indebtedness or guarantee in excess of a specified amount, (B) any other event occurs that would permit the holders of indebtedness or the beneficiaries of guarantees to become payable, or (C) certain conditions result in an early termination date under any swap contract that is in excess of $10 million, then Intermountain shall be in default under the revolving credit agreement.

Long-term debt

MDU Resources Group, Inc. On October 4, 2012, the Company amended the revolving credit agreement to increase the borrowing limit to $125.0 million and extend the termination date to October 4, 2017. The Company'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 the Company not to permit, as of the end of any fiscal quarter, (A) the ratio of funded debt to total capitalization (determined on a consolidated basis) to be greater than 65 percent or (B) the ratio of funded debt to capitalization (determined with respect to the Company alone, excluding its subsidiaries) 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.

There are no credit facilities that contain cross-default provisions between the Company and any of its subsidiaries.

MDU Energy Capital, LLC The ability to request additional borrowings under the master shelf agreement expired; however, there is debt outstanding that is reflected in the following table. The master shelf agreement contains customary covenants and provisions, including covenants of MDU Energy Capital not to permit (A) the ratio of its total debt (on a consolidated basis) to adjusted total capitalization to be greater than 70 percent, or (B) the ratio of subsidiary debt to subsidiary capitalization to be greater than 65 percent, or (C) the ratio of Intermountain’s total debt (determined on a consolidated basis) to total capitalization to be greater than 65 percent. The agreement also includes a covenant requiring the ratio of MDU Energy Capital earnings before interest and taxes to interest expense (on a consolidated basis), for the 12-month period ended each fiscal quarter, to be greater than 1.5 to 1. In addition, payment obligations under the master shelf agreement may be accelerated upon the occurrence of an event of default (as described in the agreement).

MDU Energy Capital entered into a note purchase agreement on October 22, 2012, and issued $25.0 million of Senior Notes with due dates ranging from October 2022 to October 2042 at a weighted average interest rate of 4.1 percent. MDU Energy Capital contracted to issue an additional $25.0 million of Senior Notes under the agreement on May 15, 2013.

Centennial Energy Holdings, Inc. On June 8, 2012, Centennial entered into an amended and restated revolving credit agreement which replaced the previous revolving credit agreement and extended the termination date to June 8, 2017. Centennial's revolving credit agreement supports its commercial paper program. On June 28, 2012, Centennial increased its commercial paper borrowing limit to $500.0 million. 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 and certain debt outstanding under an expired uncommitted long-term master shelf agreement contain 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 (for the revolving credit agreement) and a covenant of Centennial and certain of its subsidiaries, not to permit, as of the end of any fiscal quarter, the ratio of total debt to total capitalization to be greater than 60 percent (for the master shelf agreement). The master shelf agreement also includes a covenant that does not permit the ratio of Centennial's EBITDA to interest expense, for the 12-month period ended each fiscal quarter, to be less than 1.75 to 1. Other covenants include 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.

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.

Centennial entered into a note purchase agreement on December 20, 2012, and issued $150.0 million of Senior Notes with due dates ranging from December 2019 to December 2027 at a weighted average interest rate of 4.6 percent. Centennial contracted to issue an additional $100.0 million of Senior Notes under the agreement on February 20, 2013.

On January 11, 2013, Centennial entered into a letter of credit agreement for the issuance of up to $29.0 million of letters of credit. This agreement will expire on January 11, 2015.

WBI Energy Transmission The ability to request additional borrowings under the uncommitted long-term private shelf agreement expired in 2011; however, there is debt outstanding that is reflected in the following table. The uncommitted long-term private shelf 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 limitation on priority debt and some restrictions on the sale of certain assets and the making of certain investments.

Long-term Debt Outstanding Long-term debt outstanding at December 31 was as follows:



	2012			2011
	(In thousands)
Senior Notes at a weighted average rate of 5.74%, due on dates ranging from January 17, 2013 to May 15, 2043	$	1,349,160		$	1,287,576
Commercial paper at a weighted average rate of .51%, supported by revolving credit agreements	293,000			—
Medium-Term Notes at a weighted average rate of 7.58%, due on dates ranging from February 4, 2013 to March 16, 2029	59,000			81,000
Other notes at a weighted average rate of 5.24%, due on dates ranging from September 1, 2020 to February 1, 2035	40,090			40,469
Credit agreements at a weighted average rate of 5.22%, due on dates ranging from November 27, 2013 to November 30, 2038	3,768			15,633
Discount	(43		)	—
Total long-term debt	1,744,975			1,424,678
Less current maturities	134,108			139,267
Net long-term debt	$	1,610,867		$	1,285,411

The amounts of scheduled long-term debt maturities for the five years and thereafter following December 31, 2012, aggregate $134.1 million in 2013; $9.3 million in 2014; $266.5 million in 2015; $288.5 million in 2016; $336.4 million in 2017 and $710.2 million thereafter.