Common Stock	6 Months Ended
Jun. 30, 2016
Text Block [Abstract]
Common Stock	Note 5 – Common Stock On March 10, 2015, the Company filed with the Securities Exchange Commission (“SEC”) an automatic shelf registration statement on Form S-3 (File No. 333-202633), which became effective upon filing, for the offer and sale of up to $100,000,000 of the Company’s common stock from time to time in at-the-market offerings under the prospectus included therein and in accordance with the Sales Agency Agreement, dated March 10, 2015, between the Company and BNY Mellon Capital Markets, LLC (the “Equity Shelf Program”). During the three and six months ended June 30, 2016, the Company sold no shares through the continuous equity offering program. Since the start of the program in March 2015, the Company has sold an aggregate of 645,225 shares of common stock under this program resulting in proceeds to the Company of $35,167,584, net of $355,228 in agent commissions. As of June 30, 2016, the Company had up to $64,477,188 of common stock available for sale under the program. Net proceeds from the sale of shares of common stock under the Equity Shelf Program are intended for general corporate purposes, including the acquisition of property for the construction, completion, extension or improvement of pipeline systems and facilities located in and around the communities Southwest serves. In addition, during the six months ended June 30, 2016, the Company issued approximately 99,000 shares of common stock through the Stock Incentive Plan, Restricted Stock/Unit Plan, and Management Incentive Plan.

Note 5 – Common Stock

On March 10, 2015, the Company filed with the Securities Exchange Commission (“SEC”) an automatic shelf registration statement on Form S-3 (File No. 333-202633), which became effective upon filing, for the offer and sale of up to $100,000,000 of the Company’s common stock from time to time in at-the-market offerings under the prospectus included therein and in accordance with the Sales Agency Agreement, dated March 10, 2015, between the Company and BNY Mellon Capital Markets, LLC (the “Equity Shelf Program”). During the three and six months ended June 30, 2016, the Company sold no shares through the continuous equity offering program. Since the start of the program in March 2015, the Company has sold an aggregate of 645,225 shares of common stock under this program resulting in proceeds to the Company of $35,167,584, net of $355,228 in agent commissions. As of June 30, 2016, the Company had up to $64,477,188 of common stock available for sale under the program. Net proceeds from the sale of shares of common stock under the Equity Shelf Program are intended for general corporate purposes, including the acquisition of property for the construction, completion, extension or improvement of pipeline systems and facilities located in and around the communities Southwest serves.

In addition, during the six months ended June 30, 2016, the Company issued approximately 99,000 shares of common stock through the Stock Incentive Plan, Restricted Stock/Unit Plan, and Management Incentive Plan.