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Subsequent event | 9 Months Ended
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Sep. 30, 2014
Subsequent Events [Abstract] |
Subsequent event | Subsequent Events On September 24, 2014, Knife River provided notice to the plan administrator under one of the multiemployer pension plans to which Knife River is a party that it was withdrawing from the plan effective October 26, 2014. The plan administrator will determine Knife River's withdrawal liability, which the Company currently estimates at approximately $14 million (approximately $8.4 million after tax). Actual withdrawal liability costs may be significantly different. On October 31, 2014, the Company’s board of directors approved a plan to market the Company’s Fidelity assets and potentially exit the oil and natural gas exploration and production business. During the marketing and sales process, Fidelity intends to focus on production and continue to develop its acreage. The Company believes that the potential sale of the Fidelity assets will allow it to focus on growing its utility, pipeline and construction businesses and lower its overall business-risk profile.

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- Definition The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business. + References No definition available. + Details
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