| **New Accounting Pronouncements**                                                 | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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| **New Accounting Pronouncements and Changes in Accounting Principles [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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| New Accounting Pronouncements                                                     | New Accounting Pronouncements Revenue recognition – In May 2014, the  Financial Accounting Standards Board (FASB) issued new revenue recognition guidance to provide a single, comprehensive revenue recognition model for all contracts with customers.  Under the new guidance, an entity will recognize revenue to depict the transfer of promised goods or services to customers at an amount that the entity expects to be entitled to in exchange for those goods or services.  A five step model has been introduced for an entity to apply when recognizing revenue.  The new guidance also includes enhanced disclosure requirements and is effective January 1, 2018, with early adoption permitted for January 1, 2017.  Entities have the option to apply the new guidance under a retrospective approach to each prior reporting period presented, or a modified retrospective approach with the cumulative effect of initially applying the new guidance recognized at the date of initial application within the Consolidated Statement of Changes in Stockholder's Equity.  We plan to adopt the new guidance effective January 1, 2018 and do not expect the adoption to have a material impact on our financial statements.Variable interest entities (VIEs) – In February 2015, the FASB issued accounting guidance on the consolidation of VIEs.  The new guidance revises previous guidance by establishing an analysis for determining whether a limited partnership or similar entity is a VIE and whether outsourced decision-maker fees are considered variable interests.  In addition, the new guidance revises how a reporting entity evaluates economics and related parties when assessing who should consolidate a VIE.  The guidance was effective January 1, 2016 and did not have a material impact on our financial statements.Presentation of debt issuance costs – In April 2015, the FASB issued accounting guidance which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability.  Prior to the issuance of the new guidance, debt issuance costs were required to be presented in the balance sheet as an asset.  The guidance was effective January 1, 2016 and was applied retrospectively.  The adoption did not have a material impact on our financial statements.Recognition and measurement of financial assets and financial liabilities – In January 2016, the FASB issued accounting guidance that affects the accounting for equity investments, financial liabilities accounted for under the fair value option and the presentation and disclosure requirements for financial instruments. Under the new guidance, all equity investments in unconsolidated entities (other than those accounted for using the equity method of accounting) will generally be measured at fair value through earnings. There will no longer be an available-for-sale classification for equity securities with readily determinable fair values. For financial liabilities when the fair value option has been elected, changes in fair value due to instrument-specific credit risk will be recognized separately in other comprehensive income. In addition, the FASB clarified guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities. The new guidance is effective January 1, 2018, with the cumulative effect adjustment from initially applying the new guidance recognized in the Consolidated Statement of Financial Position as of the beginning of the year of adoption.  We do not expect the adoption to have a material impact on our financial statements.Lease accounting – In February 2016, the FASB issued accounting guidance that revises the accounting for leases.  Under the new guidance, lessees are required to recognize a right-of-use asset and a lease liability for all leases.  The new guidance will continue to classify leases as either financing or operating, with classification affecting the pattern of expense recognition.  The accounting applied by a lessor under the new guidance will be substantially equivalent to current lease accounting guidance.  The new guidance is effective January 1, 2019 with early adoption permitted.  The new standard is required to be applied with a modified retrospective approach to each prior reporting period presented and provides for certain practical expedients.  We are in the process of evaluating the effect of the new guidance on our financial statements.Measurement of credit losses on financial instruments – In June 2016, the FASB issued accounting guidance to introduce a new model for recognizing credit losses on financial instruments based on an estimate of current expected credit losses.  The new guidance will apply to loans, accounts receivable, trade receivables, other financial assets measured at amortized cost, loan commitments and other off-balance sheet credit exposures.  The new guidance will also apply to debt securities and other financial assets measured at fair value through other comprehensive income.  The new guidance is effective January 1, 2020, with early adoption permitted beginning January 1, 2019.  We are in the process of evaluating the effect of the new guidance on our financial statements.Classification for certain cash receipts and cash payments – In August 2016, the FASB issued accounting guidance related to the presentation and classification of certain transactions in the statement of cash flows where diversity in practice exists.  The guidance is effective January 1, 2018 with early adoption permitted.  We do not expect the adoption to have a material impact on our financial statements. |

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| - Definition
Tabular disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.
+ References
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