XML 38 R27.htm IDEA: XBRL DOCUMENT v3.24.2.u1
Subsequent event
6 Months Ended
Jun. 30, 2024
Subsequent Events [Abstract]  
Subsequent event Subsequent event
On July 11, 2024, Montana-Dakota issued $125.0 million of senior notes under a note purchase agreement with maturity dates ranging from July 11, 2039 to July 11, 2054, at a weighted average interest rate of 5.96 percent. The agreement contains customary covenants and provisions, including a covenant of Montana-Dakota not to permit, at any time, the ratio of total debt to total capitalization to be greater than 65 percent.