EQUITY (Notes)	9 Months Ended
Sep. 30, 2018
Equity [Abstract]
EQUITY	EQUITY Noncontrolling Interests - As a result of the Merger Transaction in 2017, we and our subsidiaries owned 100 percent of ONEOK Partners at September 30, 2018, and December 31, 2017. At December 31, 2017, the caption “Noncontrolling interests” on our Consolidated Balance Sheet reflects only the 20 percent of WTLPG that we did not own. On July 31, 2018, we acquired the remaining 20 percent interest in WTLPG for $195 million with cash on hand. We are now the sole owner of the West Texas LPG pipeline system. Equity Issuances - In January 2018, we completed an underwritten public offering of 21.9 million shares of our common stock at a public offering price of $54.50 per share, generating net proceeds of $1.2 billion. We used the net proceeds from this offering to fund capital expenditures and for general corporate purposes, which included repaying a portion of our outstanding indebtedness. In July 2017, we established an “at-the-market” equity program for the offer and sale from time to time of our common stock up to an aggregate amount of $1 billion. The program allows us to offer and sell our common stock at prices we deem appropriate through a sales agent. Sales of our common stock may be made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between us and the sales agent. We are under no obligation to offer and sell common stock under the program. During the nine months ended September 30, 2018, no shares were sold through our “at-the-market” equity program. During the year ended December 31, 2017, we sold 8.4 million shares of common stock through our “at-the-market” equity program that resulted in net proceeds of $448.3 million. The net proceeds from these issuances were used for general corporate purposes, including repayment of outstanding indebtedness and to fund capital expenditures. Dividends - Holders of our common stock share equally in any dividend declared by our board of directors, subject to the rights of the holders of outstanding preferred stock. Dividends paid on our common stock in February 2018, May 2018 and August 2018 were $0.77, $0.795 and $0.825 per share, respectively. A dividend of $0.855 per share was declared for shareholders of record at the close of business on November 5, 2018, payable November 14, 2018. The Series E Preferred Stock pays quarterly dividends on each share of Series E Preferred Stock, when, as and if declared by our Board of Directors, at a rate of 5.5 percent per year. We paid dividends for the Series E Preferred Stock of $0.3 million each in February 2018, May 2018 and August 2018. Dividends totaling $0.3 million were declared for the Series E Preferred Stock and are payable November 14, 2018. Cash Distributions - Prior to the consummation of the Merger Transaction, we received distributions from ONEOK Partners on our common and Class B units and our 2 percent general partner interest, which included our incentive distribution rights. As a result of the Merger Transaction in 2017, we are entitled to receive all available ONEOK Partners cash. Our incentive distribution rights effectively terminated at the closing of the Merger Transaction.

EQUITY

Noncontrolling Interests - As a result of the Merger Transaction in 2017, we and our subsidiaries owned 100 percent of ONEOK Partners at September 30, 2018, and December 31, 2017. At December 31, 2017, the caption “Noncontrolling interests” on our Consolidated Balance Sheet reflects only the 20 percent of WTLPG that we did not own. On July 31, 2018, we acquired the remaining 20 percent interest in WTLPG for $195 million with cash on hand. We are now the sole owner of the West Texas LPG pipeline system.

Equity Issuances - In January 2018, we completed an underwritten public offering of 21.9 million shares of our common stock at a public offering price of $54.50 per share, generating net proceeds of $1.2 billion. We used the net proceeds from this offering to fund capital expenditures and for general corporate purposes, which included repaying a portion of our outstanding indebtedness.

In July 2017, we established an “at-the-market” equity program for the offer and sale from time to time of our common stock up to an aggregate amount of $1 billion. The program allows us to offer and sell our common stock at prices we deem appropriate through a sales agent. Sales of our common stock may be made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between us and the sales agent. We are under no obligation to offer and sell common stock under the program. During the nine months ended September 30, 2018, no shares were sold through our “at-the-market” equity program.

During the year ended December 31, 2017, we sold 8.4 million shares of common stock through our “at-the-market” equity program that resulted in net proceeds of $448.3 million. The net proceeds from these issuances were used for general corporate purposes, including repayment of outstanding indebtedness and to fund capital expenditures.

Dividends - Holders of our common stock share equally in any dividend declared by our board of directors, subject to the rights of the holders of outstanding preferred stock. Dividends paid on our common stock in February 2018, May 2018 and August 2018 were $0.77, $0.795 and $0.825 per share, respectively. A dividend of $0.855 per share was declared for shareholders of record at the close of business on November 5, 2018, payable November 14, 2018.

The Series E Preferred Stock pays quarterly dividends on each share of Series E Preferred Stock, when, as and if declared by our Board of Directors, at a rate of 5.5 percent per year. We paid dividends for the Series E Preferred Stock of $0.3 million each in February 2018, May 2018 and August 2018. Dividends totaling $0.3 million were declared for the Series E Preferred Stock and are payable November 14, 2018.

Cash Distributions - Prior to the consummation of the Merger Transaction, we received distributions from ONEOK Partners on our common and Class B units and our 2 percent general partner interest, which included our incentive distribution rights.

As a result of the Merger Transaction in 2017, we are entitled to receive all available ONEOK Partners cash. Our incentive distribution rights effectively terminated at the closing of the Merger Transaction.