Preferred Stock (Details Textual) $ / shares in Units, $ in Thousands, $ in Millions													3 Months Ended		9 Months Ended
	Aug. 26, 2019 USD ($)	Aug. 13, 2019 USD ($)	Aug. 13, 2019 CAD ($)	May 20, 2019 USD ($)	Apr. 15, 2019 USD ($)	Apr. 15, 2019 CAD ($)	Mar. 01, 2019 USD ($)	Feb. 25, 2019 USD ($) $ / shares shares	Feb. 25, 2019 CAD ($)	Nov. 26, 2018 USD ($)	Aug. 29, 2018 USD ($)	May 25, 2018 USD ($)	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 shares
Preferred Stock, Shares Issued | shares													350,000		350,000		350,000
Dividends, Preferred Stock, Paid-in-kind | $													$ 6,657	$ 6,193	$ 19,627	$ 11,023
Redeemable Preferred Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion | shares													11,726,909		11,726,909
Dividends, Preferred Stock, Paid-in-kind | $	$ 6,657			$ 6,541			$ 6,430			$ 6,317	$ 6,211	$ 4,832
Subsidiary redeemable preferred stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion | shares													309,097		309,097
Subsidiary Preferred Stock, Issuers Redemption Period								3 years	3 years
Dividends, Preferred Stock, Paid-in-kind		$ 5,000	$ 6.6		$ 1,900	$ 2.5
SemCAMS Midstream [Member] | Subsidiary redeemable preferred stock [Member]
Preferred Stock, Shares Issued | shares								300,000
Proceeds from Issuance of Redeemable Preferred Stock								$ 223,800	$ 293.7
Payments of Stock Issuance Costs								$ 4,800	$ 6.3
Canada, Dollars | SemCAMS Midstream [Member] | Subsidiary redeemable preferred stock [Member]
Shares Issued, Price Per Share								$ 1,000
Preferred stock per share annualized dividend								87.50
Preferred Stock, Redemption Price Per Share								1,100
United States of America, Dollars | SemCAMS Midstream [Member] | Subsidiary redeemable preferred stock [Member]
Shares Issued, Price Per Share								755
Preferred Stock, Redemption Price Per Share								$ 831