Income Taxes	9 Months Ended
Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES: The Company's effective income tax rate for the three months ended September 30, 2016 was 25.7%, compared with 36.8% for the three months ended September 30, 2015. The Company's effective income tax rate for the nine months ended September 30, 2016 was 29.2% compared with 37.2% for the nine months ended September 30, 2015. The Company's provision for income taxes for the three and nine months ended September 30, 2016 included an income tax benefit of $7.8 million and $21.4 million, respectively, associated with the United States Short Line Tax Credit. In December 2015, the United States Short Line Tax Credit (which had previously expired on December 31, 2014), was extended for fiscal years 2015 and 2016. As the extension was passed in December 2015 for the full 2015 fiscal year, the United States Short Line Tax Credit associated with results for the three and nine months ended September 30, 2015 was recorded in the fourth quarter of 2015. The United States Short Line Tax Credit is an income tax track maintenance credit for Class II and Class III railroads to reduce their federal income tax based on qualified railroad track maintenance expenditures. Qualified expenditures include amounts incurred for maintaining track, including roadbed, bridges and related track structures owned or leased by a Class II or Class III railroad. The credit is equal to 50% of the qualified expenditures, subject to an annual limitation of $3,500 multiplied by the number of miles of railroad track owned or leased by the Class II or Class III railroad as of the end of its tax year. The Company's provision for income taxes for the three and nine months ended September 30, 2016 also included a $4.3 million income tax benefit as a result of the Company remeasuring its deferred income tax assets and liabilities in the U.K. based on the newly enacted change to the corporate income tax rate by the U.K. government that will apply when the temporary differences are expected to be realized or settled. The Company's provision for income taxes for the nine months ended September 30, 2016 also included a valuation allowance of A$2.6 million (or $2.0 million at the average exchange rate in March of 2016) associated with the impairment of GWA's now idle rolling-stock maintenance facility (see Note 2, Changes in Operations) that was formerly used in connection with the Southern Iron rail haulage agreement. In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes, which requires that deferred tax liabilities and assets be classified as non-current in a classified statement of financial position. For public entities, the amendments in this guidance are effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Earlier application is permitted as of the beginning of an interim or annual reporting period. The Company early adopted the provisions of this ASU as of January 1, 2016 and applied it retrospectively to all periods presented. The December 31, 2015 consolidated balance sheet was adjusted to reflect a reduction of current deferred income tax assets of $69.2 million, an increase in non-current deferred income tax assets of $0.2 million and a reduction in non-current deferred income tax liabilities of $69.0 million. There was no other impact on the consolidated financial statements from the adoption of this guidance.

INCOME TAXES:

The Company's effective income tax rate for the three months ended September 30, 2016 was 25.7%, compared with 36.8% for the three months ended September 30, 2015. The Company's effective income tax rate for the nine months ended September 30, 2016 was 29.2% compared with 37.2% for the nine months ended September 30, 2015. The Company's provision for income taxes for the three and nine months ended September 30, 2016 included an income tax benefit of $7.8 million and $21.4 million, respectively, associated with the United States Short Line Tax Credit. In December 2015, the United States Short Line Tax Credit (which had previously expired on December 31, 2014), was extended for fiscal years 2015 and 2016. As the extension was passed in December 2015 for the full 2015 fiscal year, the United States Short Line Tax Credit associated with results for the three and nine months ended September 30, 2015 was recorded in the fourth quarter of 2015.

The United States Short Line Tax Credit is an income tax track maintenance credit for Class II and Class III railroads to reduce their federal income tax based on qualified railroad track maintenance expenditures. Qualified expenditures include amounts incurred for maintaining track, including roadbed, bridges and related track structures owned or leased by a Class II or Class III railroad. The credit is equal to 50% of the qualified expenditures, subject to an annual limitation of $3,500 multiplied by the number of miles of railroad track owned or leased by the Class II or Class III railroad as of the end of its tax year.

The Company's provision for income taxes for the three and nine months ended September 30, 2016 also included a $4.3 million income tax benefit as a result of the Company remeasuring its deferred income tax assets and liabilities in the U.K. based on the newly enacted change to the corporate income tax rate by the U.K. government that will apply when the temporary differences are expected to be realized or settled. The Company's provision for income taxes for the nine months ended September 30, 2016 also included a valuation allowance of A$2.6 million (or $2.0 million at the average exchange rate in March of 2016) associated with the impairment of GWA's now idle rolling-stock maintenance facility (see Note 2, Changes in Operations) that was formerly used in connection with the Southern Iron rail haulage agreement.

In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes, which requires that deferred tax liabilities and assets be classified as non-current in a classified statement of financial position. For public entities, the amendments in this guidance are effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Earlier application is permitted as of the beginning of an interim or annual reporting period. The Company early adopted the provisions of this ASU as of January 1, 2016 and applied it retrospectively to all periods presented. The December 31, 2015 consolidated balance sheet was adjusted to reflect a reduction of current deferred income tax assets of $69.2 million, an increase in non-current deferred income tax assets of $0.2 million and a reduction in non-current deferred income tax liabilities of $69.0 million. There was no other impact on the consolidated financial statements from the adoption of this guidance.