Recently issued accounting standards	12 Months Ended
Dec. 31, 2017
Accounting Policies [Abstract]
Recently issued accounting standards	Recently issued accounting standards In May 2014, the Financial Accounting Standards Board ("FASB"), in a joint effort with the International Accounting Standards Board ("IASB"), issued new accounting guidance to clarify the principles for recognizing revenue. This new guidance, collectively with related guidance provided by the FASB, is designed to enhance the comparability of revenue recognition practices across entities, industries, jurisdictions and capital markets, and will affect any entity that enters into contracts with customers or enters into contracts for the transfer of nonfinancial assets, unless those contracts are within the scope of other standards. The new guidance establishes principles for reporting information to users of financial statements about the nature, amount, timing, and uncertainty of revenue and cash flows arising from an entity's contracts with customers. The core principle of the new guidance is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. The new guidance is effective for annual periods beginning after December 15, 2017 and interim periods within those years. The Company adopted the new standard on January 1, 2018 using the modified retrospective method of adoption, which involves recognizing the cumulative effect of adopting this guidance as an adjustment to the Company's opening balance of retained earnings on the adoption date. The adoption of this guidance did not have a material impact on the Company's consolidated results of operations, cash flows and financial position. In February 2016, the FASB issued guidance that will change the requirements for accounting for leases. Under the new guidance, lessees (including lessees under leases classified as finance leases, which are to be classified based on criteria similar to that applicable to capital leases under current guidance, and leases classified as operating leases) will recognize a right-to-use asset and a lease liability on the balance sheet, initially measured as the present value of lease payments under the lease. Under current guidance, operating leases are not recognized on the balance sheet. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted. The new standard must be adopted using a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements; the guidance provides certain practical expedients. The Company is currently evaluating this guidance to determine its impact on the Company’s results of operations, cash flows and financial position. In March 2016, the FASB issued new guidance designed to simplify several aspects of the accounting for share-based payment transactions, including, among other things, guidance related to accounting for income taxes, modification of the criteria for classification of awards as either equity awards or liability awards where an employer withholds shares from an employee's share-based award for tax withholding purposes, and classification on the statement of cash flows of cash payments to a tax authority by an employer that withholds shares from an employee's award for tax withholding purposes. The Company adopted this guidance as of January 1, 2017. The Company has applied the new guidance requiring recognition of excess tax deficiencies and tax benefits in the consolidated statement of income, rather than in additional paid-in-capital, as previously required. The adoption of the new standard increased net income and cash flows from operating activities by $6.6 million and increased diluted earnings per share by $0.14 for the year ended December 31, 2017. The Company will continue to estimate forfeitures of share-based awards at the time of grant, rather than recognize actual forfeitures as they occur, as permitted under the new guidance. In August 2016, the FASB issued new guidance with regard to eight specific issues pertaining to the classification of certain cash receipts and cash payments within the statement of cash flows. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. The Company adopted this guidance on January 1, 2018. The adoption of the guidance did not have a material impact on its cash flows. In October 2016, the FASB issued new guidance requiring companies to recognize the income tax effects of intra-entity sales and transfers of assets, other than inventory, in the income statement as income tax expense (or benefit) in the period in which the transfer occurs. Previously, recognition was prohibited until the assets were sold to an outside party or otherwise utilized. The guidance is effective for annual periods beginning after December 15, 2017. The guidance should be applied on a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the annual period of adoption. The Company adopted this guidance on January 1, 2018. The adoption of the guidance did not have a material effect on its consolidated financial statements. In January 2017, the FASB issued new guidance to clarify the definition of a “business,” with the objective of assisting entities in evaluating whether a transaction should be accounted for as an acquisition (or disposal) of assets or as an acquisition of a business. The definition of a business affects many areas of accounting, including acquisitions, disposals, goodwill and consolidation. The guidance generally defines a business as an integrated set of activities and assets (collectively referred to as a “set”) that is capable of being conducted and managed for the purpose of providing a return to investors or other owners, members, or participants. The guidance further provides that, to be considered a business, a set must meet specified requirements. However, the guidance also states that, if substantially all of the fair value of gross assets acquired (subject to specified exceptions) is concentrated in a single identifiable asset or group of similar identifiable assets, the set is not considered a business and no further analysis is required. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. The guidance permits early adoption, and the Company adopted this guidance during the fourth quarter 2017. The adoption of the guidance did not have a material effect on its consolidated financial statements. In January 2017, the FASB issued guidance to simplify the quantitative test for goodwill impairment. Under current guidance, if a reporting unit’s carrying value exceeds its fair value, the entity must determine the implied value of goodwill. This determination is made by deducting the fair value of a reporting unit’s identifiable assets and liabilities from the fair value of the reporting unit as a whole as if the reporting unit had just been acquired. Under the new guidance, a determination of the implied value of goodwill will no longer be required; a goodwill impairment will be equal to the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. The revised guidance is effective for fiscal years, and any interim goodwill impairment tests within those fiscal years, beginning after December 15, 2019. Early adoption is permitted for any impairment tests performed after January 1, 2017. The Company is evaluating the impact of the adoption of this guidance, but currently does not anticipate the guidance will have a material impact on its consolidated financial position or results of operations. In March 2017, the FASB issued guidance for employers that sponsor defined benefit pension or other postretirement benefit plans. The guidance requires that these employers disaggregate specified components of net periodic pension cost and net periodic postretirement benefit cost (collectively, "net benefit cost"). Specifically, the guidance generally requires employers to present in the income statement the service cost component of net benefit cost in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017 and generally is required to be applied retrospectively. The Company adopted this guidance on January 1, 2018. The adoption of the guidance did not have a material impact on the consolidated financial statements. In August 2017, the FASB issued guidance with the objective of improving the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements. The new guidance provides for changes to current designation and measurement guidance for qualifying hedging relationships and to the method of presenting hedge results. In addition, the new guidance includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. The new guidance is effective for reporting periods beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations and financial position. In February 2018, the FASB issued an amendment to the guidance on comprehensive income. The amendment permits a company to reclassify the income tax effects of the Tax Cuts and Jobs Act ("the TCJA") on items within accumulated other comprehensive income to retained earnings. The amendment also requires certain new disclosures about these stranded tax effects. The guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted for reporting periods for which financial statements have not yet been issued. The new guidance can be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the 2017 Act is recognized. The Company is currently evaluating the impact this guidance will have on its consolidated financial statements. From time to time, new accounting guidance is issued by the FASB or other standard setting bodies that is adopted by the Company as of the specified effective date or, when permitted by the guidance and as determined by the Company, as of an earlier date. The Company has assessed recently issued guidance that is not yet effective and believes the new guidance will not have a material impact on the Company’s results of operations, cash flows or financial position.

Recently issued accounting standards

In May 2014, the Financial Accounting Standards Board ("FASB"), in a joint effort with the International Accounting Standards Board ("IASB"), issued new accounting guidance to clarify the principles for recognizing revenue. This new guidance, collectively with related guidance provided by the FASB, is designed to enhance the comparability of revenue recognition practices across entities, industries, jurisdictions and capital markets, and will affect any entity that enters into contracts with customers or enters into contracts for the transfer of nonfinancial assets, unless those contracts are within the scope of other standards. The new guidance establishes principles for reporting information to users of financial statements about the nature, amount, timing, and uncertainty of revenue and cash flows arising from an entity's contracts with customers. The core principle of the new guidance is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. The new guidance is effective for annual periods beginning after December 15, 2017 and interim periods within those years. The Company adopted the new standard on January 1, 2018 using the modified retrospective method of adoption, which involves recognizing the cumulative effect of adopting this guidance as an adjustment to the Company's opening balance of retained earnings on the adoption date. The adoption of this guidance did not have a material impact on the Company's consolidated results of operations, cash flows and financial position.

In February 2016, the FASB issued guidance that will change the requirements for accounting for leases. Under the new guidance, lessees (including lessees under leases classified as finance leases, which are to be classified based on criteria similar to that applicable to capital leases under current guidance, and leases classified as operating leases) will recognize a right-to-use asset and a lease liability on the balance sheet, initially measured as the present value of lease payments under the lease. Under current guidance, operating leases are not recognized on the balance sheet. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted. The new standard must be adopted using a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements; the guidance provides certain practical expedients. The Company is currently evaluating this guidance to determine its impact on the Company’s results of operations, cash flows and financial position.

In March 2016, the FASB issued new guidance designed to simplify several aspects of the accounting for share-based payment transactions, including, among other things, guidance related to accounting for income taxes, modification of the criteria for classification of awards as either equity awards or liability awards where an employer withholds shares from an employee's share-based award for tax withholding purposes, and classification on the statement of cash flows of cash payments to a tax authority by an employer that withholds shares from an employee's award for tax withholding purposes. The Company adopted this guidance as of January 1, 2017. The Company has applied the new guidance requiring recognition of excess tax deficiencies and tax benefits in the consolidated statement of income, rather than in additional paid-in-capital, as previously required. The adoption of the new standard increased net income and cash flows from operating activities by $6.6 million and increased diluted earnings per share by $0.14 for the year ended December 31, 2017. The Company will continue to estimate forfeitures of share-based awards at the time of grant, rather than recognize actual forfeitures as they occur, as permitted under the new guidance.

In August 2016, the FASB issued new guidance with regard to eight specific issues pertaining to the classification of certain cash receipts and cash payments within the statement of cash flows. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. The Company adopted this guidance on January 1, 2018. The adoption of the guidance did not have a material impact on its cash flows.

In October 2016, the FASB issued new guidance requiring companies to recognize the income tax effects of intra-entity sales and transfers of assets, other than inventory, in the income statement as income tax expense (or benefit) in the period in which the transfer occurs. Previously, recognition was prohibited until the assets were sold to an outside party or otherwise utilized. The guidance is effective for annual periods beginning after December 15, 2017. The guidance should be applied on a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the annual period of adoption. The Company adopted this guidance on January 1, 2018. The adoption of the guidance did not have a material effect on its consolidated financial statements.

In January 2017, the FASB issued new guidance to clarify the definition of a “business,” with the objective of assisting entities in evaluating whether a transaction should be accounted for as an acquisition (or disposal) of assets or as an acquisition of a business. The definition of a business affects many areas of accounting, including acquisitions, disposals, goodwill and consolidation. The guidance generally defines a business as an integrated set of activities and assets (collectively referred to as a “set”) that is capable of being conducted and managed for the purpose of providing a return to investors or other owners, members, or participants. The guidance further provides that, to be considered a business, a set must meet specified requirements. However, the guidance also states that, if substantially all of the fair value of gross assets acquired (subject to specified exceptions) is concentrated in a single identifiable asset or group of similar identifiable assets, the set is not considered a business and no further analysis is required. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. The guidance permits early adoption, and the Company adopted this guidance during the fourth quarter 2017. The adoption of the guidance did not have a material effect on its consolidated financial statements.

In January 2017, the FASB issued guidance to simplify the quantitative test for goodwill impairment. Under current guidance, if a reporting unit’s carrying value exceeds its fair value, the entity must determine the implied value of goodwill. This determination is made by deducting the fair value of a reporting unit’s identifiable assets and liabilities from the fair value of the reporting unit as a whole as if the reporting unit had just been acquired. Under the new guidance, a determination of the implied value of goodwill will no longer be required; a goodwill impairment will be equal to the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. The revised guidance is effective for fiscal years, and any interim goodwill impairment tests within those fiscal years, beginning after December 15, 2019. Early adoption is permitted for any impairment tests performed after January 1, 2017. The Company is evaluating the impact of the adoption of this guidance, but currently does not anticipate the guidance will have a material impact on its consolidated financial position or results of operations.

In March 2017, the FASB issued guidance for employers that sponsor defined benefit pension or other postretirement benefit plans. The guidance requires that these employers disaggregate specified components of net periodic pension cost and net periodic postretirement benefit cost (collectively, "net benefit cost"). Specifically, the guidance generally requires employers to present in the income statement the service cost component of net benefit cost in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017 and generally is required to be applied retrospectively. The Company adopted this guidance on January 1, 2018. The adoption of the guidance did not have a material impact on the consolidated financial statements.

In August 2017, the FASB issued guidance with the objective of improving the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements. The new guidance provides for changes to current designation and measurement guidance for qualifying hedging relationships and to the method of presenting hedge results. In addition, the new guidance includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. The new guidance is effective for reporting periods beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations and financial position.

In February 2018, the FASB issued an amendment to the guidance on comprehensive income. The amendment permits a company to reclassify the income tax effects of the Tax Cuts and Jobs Act ("the TCJA") on items within accumulated other comprehensive income to retained earnings. The amendment also requires certain new disclosures about these stranded tax effects. The guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted for reporting periods for which financial statements have not yet been issued. The new guidance can be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the 2017 Act is recognized. The Company is currently evaluating the impact this guidance will have on its consolidated financial statements.

From time to time, new accounting guidance is issued by the FASB or other standard setting bodies that is adopted by the Company as of the specified effective date or, when permitted by the guidance and as determined by the Company, as of an earlier date. The Company has assessed recently issued guidance that is not yet effective and believes the new guidance will not have a material impact on the Company’s results of operations, cash flows or financial position.