New accounting standards (Policies)	6 Months Ended
Jun. 28, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New accounting standards	New 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. The new guidance 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. In July 2015, the FASB deferred the effective date of the new guidance. The guidance is effective prospectively for annual periods beginning after December 15, 2017 and interim periods within those years; early application is permitted for annual periods beginning after December 15, 2016. The Company is currently evaluating this guidance to determine the impact on the Company’s results of operations, cash flows and financial position. In April 2015, FASB issued guidance for the reporting of debt issuance costs within the balance sheet. Under the new guidance, debt issuance costs are to be presented in the balance sheet as a direct deduction from the associated debt liability, consistent with the presentation of a debt discount. Currently, debt issuance costs are presented as a deferred charge (i.e., an asset) on the balance sheet. In addition to providing uniform treatment for debt issuance costs and debt discounts, the guidance is consistent with other FASB guidance, which states that debt issuance costs are similar to debt discounts because they reduce the proceeds of borrowing (thereby increasing the effective interest rate) and cannot be an asset because they provide no future economic benefit. The new guidance is effective for fiscal years beginning after December 15, 2015 with early adoption permitted, and is required to be applied on a retrospective basis. The Company does not believe that the adoption of this guidance will have a material impact on the Company’s financial position. From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that are adopted by the Company as of the specified effective date or, in some cases where early adoption is permitted, in advance of the specified effective date. The Company has assessed the recently issued standards that are not yet effective and, unless otherwise discussed above, believes these standards will not have a material impact on the Company’s results of operations, cash flows or financial position.

New 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. The new guidance 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. In July 2015, the FASB deferred the effective date of the new guidance. The guidance is effective prospectively for annual periods beginning after December 15, 2017 and interim periods within those years; early application is permitted for annual periods beginning after December 15, 2016. The Company is currently evaluating this guidance to determine the impact on the Company’s results of operations, cash flows and financial position.

In April 2015, FASB issued guidance for the reporting of debt issuance costs within the balance sheet. Under the new guidance, debt issuance costs are to be presented in the balance sheet as a direct deduction from the associated debt liability, consistent with the presentation of a debt discount. Currently, debt issuance costs are presented as a deferred charge (i.e., an asset) on the balance sheet. In addition to providing uniform treatment for debt issuance costs and debt discounts, the guidance is consistent with other FASB guidance, which states that debt issuance costs are similar to debt discounts because they reduce the proceeds of borrowing (thereby increasing the effective interest rate) and cannot be an asset because they provide no future economic benefit. The new guidance is effective for fiscal years beginning after December 15, 2015 with early adoption permitted, and is required to be applied on a retrospective basis. The Company does not believe that the adoption of this guidance will have a material impact on the Company’s financial position.

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that are adopted by the Company as of the specified effective date or, in some cases where early adoption is permitted, in advance of the specified effective date. The Company has assessed the recently issued standards that are not yet effective and, unless otherwise discussed above, believes these standards will not have a material impact on the Company’s results of operations, cash flows or financial position.