Nature of Operations and Basis of Presentation (Policies)

9 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

Nature of Operations

Nature of Operations. Southwest Gas Corporation and its subsidiaries (the “Company”) consist of two segments: natural gas operations (“Southwest” or the “natural gas operations” segment) and construction services. Southwest is engaged in the business of purchasing, distributing, and transporting natural gas for customers in portions of Arizona, Nevada, and California. Public utility rates, practices, facilities, and service territories of Southwest are subject to regulatory oversight. The timing and amount of rate relief can materially impact results of operations. Natural gas sales are seasonal, peaking during the winter months; therefore, results of operations for interim periods are not necessarily indicative of results for a full year. Natural gas purchases and the timing of related recoveries can materially impact liquidity. NPL Construction Co. (“NPL” or the “construction services” segment), a wholly owned subsidiary, is a full-service underground piping contractor that primarily provides utility companies with trenching and installation, replacement, and maintenance services for energy distribution systems. Typically, NPL revenues are lowest during the first quarter of the year due to unfavorable winter weather conditions. Operating revenues typically improve as more favorable weather conditions occur during the summer and fall months.

Basis of Presentation

Basis of Presentation. The condensed consolidated financial statements included herein have been prepared by the Company, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles (“GAAP”) have been condensed or omitted pursuant to such rules and regulations. The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. In the opinion of management, all adjustments, consisting of normal recurring items and estimates necessary for a fair presentation of results for the interim periods, have been made. It is suggested that these condensed consolidated financial statements be read in conjunction with the consolidated financial statements and the notes thereto included in the 2012 Annual Report to Shareholders, which is incorporated by reference into the 2012 Form 10-K, and the first and second quarter 2013 reports on Form 10-Q.

Prepaids and Other Current Assets

Prepaids and other current assets. Prepaids and other current assets includes gas pipe inventory and operating supplies of $24 million at September 30, 2013 and $25 million at December 31, 2012.

Cash and Cash Equivalents

Cash and Cash Equivalents. For purposes of reporting consolidated cash flows, cash and cash equivalents include cash on hand and financial instruments with a purchase-date maturity of three months or less. Cash and cash equivalents fall within Level 1 (quoted prices for identical financial instruments) of the three-level fair value hierarchy that ranks the inputs used to measure fair value by their reliability. During the nine months ended September 30, 2013, approximately $7.9 million of customer advances, upon contract expiration, were applied as contributions toward utility construction activity and represent a non-cash investing activity.

Intercompany Transactions

Intercompany Transactions. NPL recognizes revenues generated from contracts with Southwest (see Note 3 - Segment Information below). Accounts receivable for these services are presented in the table below (thousands of dollars):

	September 30, 2013		December 31, 2012
Accounts receivable for NPL services	$	11,517	$	8,179

The accounts receivable balance, revenues, and associated profits are included in the condensed consolidated financial statements of the Company and were not eliminated during consolidation in accordance with accounting treatment for rate-regulated entities.

Other Property and Investments

Other Property and Investments. Other property and investments includes (millions of dollars):

	September 30, 2013			December 31, 2012
NPL property and equipment	$	315		$	287
NPL accumulated provision for depreciation and amortization		(157	)		(136	)
Net cash surrender value of COLI policies		88			80
Other property		11			11
Total	$	257		$	242

Other Income (Deductions)

Other Income (Deductions). The following table provides the composition of significant items included in Other income (deductions) on the consolidated statements of income (thousands of dollars):

	Three Months Ended						Nine Months Ended						Twelve Months Ended
	September 30						September 30						September 30
	2013			2012			2013			2012			2013			2012
Change in COLI policies	$	2,500		$	2,200		$	8,100		$	5,500		$	9,200		$	8,100
Interest income		158			280			422			785			561			962
Pipe replacement costs		(42	)		(973	)		(163	)		(2,015	)		(828	)		(3,663	)
Miscellaneous income and (expense)		52			129			(170	)		304			(907	)		577
Total other income (deductions)	$	2,668		$	1,636		$	8,189		$	4,574		$	8,026		$	5,976

Included in the table above is the change in cash surrender values of company-owned life insurance (“COLI”) policies (including net death benefits recognized). These life insurance policies on members of management and other key employees are used by Southwest to indemnify itself against the loss of talent, expertise, and knowledge, as well as to provide indirect funding for certain nonqualified benefit plans. Current tax regulations provide for tax-free treatment of life insurance (death benefit) proceeds. Therefore, changes in the cash surrender value components of COLI policies, as they progress towards the ultimate death benefits, are also recorded without tax consequences. Pipe replacement costs include amounts associated with certain Arizona non-recoverable pipe replacement work. The replacement program work subject to non-recoverability was substantially completed in 2012.

Final and Proposed Income Tax Regulations

Final and Proposed Income Tax Regulations. In September 2013, the United States Department of the Treasury and the Internal Revenue Service (“IRS”) issued final and proposed regulations for the tax treatment of tangible property. The final regulations include standards for determining whether and when a taxpayer must capitalize costs incurred in acquiring, maintaining, or improving tangible property. The final regulations are generally effective for tax years beginning on or after January 1, 2014, and may be adopted in earlier years under certain circumstances. Proposed regulations were also released that revise the rules for dispositions of tangible property and general asset accounts. The proposed regulations addressing dispositions and general asset accounts are also expected (when finalized) to be effective for tax years starting on or after January 1, 2014, and may be adopted in earlier years under certain circumstances. The Company expects the IRS to issue natural gas industry guidance which will facilitate its analysis regarding the regulations’ impact on natural gas distribution networks. Based upon preliminary analysis of the final and proposed regulations, and in anticipation of specific guidance for the natural gas industry, the Company expects the regulations could result in a modest acceleration of tax deductibility, and the deferral of tax payments.