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Debt | 3 Months Ended
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Mar. 31, 2018
Debt and Other Disclosures [Abstract] |
Debt Disclosure | Other Debt During the three months ended March 31, 2018, we made principal payments of $15.0 million on our senior secured non-recourse notes issued by Northwind Holdings, LLC. At March 31, 2018, letters of credit totaling $2.1 million had been issued from the credit facility, but there were no borrowed amounts outstanding.
Income Tax Disclosure | Income Tax On December 22, 2017, the U.S. Federal government enacted the TCJA, which reduces the federal corporate tax rate from 35 percent to 21 percent effective January 1, 2018. We are applying the guidance in Staff Accounting Bulletin (SAB) 118 when accounting for the enactment-date effects of TCJA. At March 31, 2018, our estimates recorded at December 31, 2017 for the tax effects of TCJA are not final. We will continue to refine our calculations as additional analysis is completed and record the final amounts during the one year measurement period after the enactment date as allowed by SAB 118. Tax rate estimates recorded at December 31, 2017 and March 31, 2018 may be impacted by changes in accounting and tax interpretations of the TCJA legislation.

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- Definition The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 + Details
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- Definition The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -URI http://asc.fasb.org/topic&trid=2144680 + Details
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