Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2016
Accounting Policies [Abstract]
Use of Estimates [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions about future events. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities, and reported amounts of revenues and expenses. Such estimates include the valuation of accounts receivable, inventories, goodwill, intangible assets, and other long-lived assets; legal contingencies; guarantee obligations; indemnifications; assumptions used in retirement, medical, and workers' compensation benefits; stock-based compensation; fair value measurements; income taxes; and vendor and customer rebates, among others. These estimates and assumptions are based on management's best estimates and judgment. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment, which management believes to be reasonable under the circumstances. We adjust such estimates and assumptions when facts and circumstances dictate. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in these estimates resulting from continuing changes in the economic environment will be reflected in the consolidated financial statements in future periods.
Vendor Rebates and Allowances [Policy Text Block]	Rebates and allowances received from our vendors are recognized as a reduction of "Materials, labor, and other operating expenses (excluding depreciation)" when the product is sold, unless the rebates and allowances are linked to a specific incremental cost to sell a vendor's product. Amounts received from vendors that are linked to specific selling and distribution expenses are recognized as a reduction of "Selling and distribution expenses" in the period the expense is incurred. We also provide rebates to our customers and our customers' customers based on the volume of their purchases. We provide the rebates to increase the sell-through of our products. The rebates are recorded as a decrease in "Sales."
Leases [Policy Text Block]	For purposes of determining straight-line rent expense, the lease term is calculated from the date we first take possession of the facility, including any periods of free rent and any renewal option periods we are reasonably assured of exercising.
Fair Value [Policy Text Block]	Fair Value Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The fair value hierarchy under GAAP gives the highest priority to quoted market prices (Level 1) and the lowest priority to unobservable inputs (Level 3). In general, and where applicable, we use quoted prices in active markets for identical assets or liabilities to determine fair value (Level 1). If quoted prices in active markets for identical assets or liabilities are not available to determine fair value, we use quoted prices for similar assets and liabilities or inputs that are observable either directly or indirectly (Level 2). If quoted prices for identical or similar assets are not available or are unobservable, we may use internally developed valuation models, whose inputs include bid prices, and third-party valuations utilizing underlying asset assumptions (Level 3).
Financial Instruments [Policy Text Block]	Financial Instruments Our financial instruments are cash and cash equivalents, restricted cash, accounts receivable, accounts payable, long-term debt, and interest rate swaps. Our cash and restricted cash is recorded at cost, which approximates fair value, and our cash equivalents are money market funds measured at fair value. As of September 30, 2016, and December 31, 2015, we held $98.4 million and $170.2 million, respectively, in money market funds that are measured at fair value on a recurring basis using Level 1 inputs. The recorded values of accounts receivable and accounts payable approximate fair values based on their short-term nature. At September 30, 2016 and December 31, 2015, the book value of our fixed-rate debt was $465.5 million and $300.0 million, respectively, and the fair value was estimated to be $474.6 million and $309.0 million, respectively. The difference between the book value and the fair value is derived from the difference between the period-end market interest rate and the stated rate of our fixed-rate, long-term debt. We estimated the fair value of our fixed-rate debt using quoted market prices of our debt in inactive markets (Level 2 inputs). The interest rate on our term loans and revolving credit facility are based on market rates such as the London Interbank Offered Rate (LIBOR) or a base rate. Because the interest rate on the term loans and revolving credit facility are based on current market rates, we believe that the estimated fair value of the outstanding balance on our term loans and revolving credit facility approximates book value. As discussed below, we also have interest rate swaps to mitigate our variable interest rate exposure, the fair value of which is measured based on Level 2 inputs.
Derivatives, Interest Rate Swaps [Policy Text Block]	The interest rate swap agreements were not designated as cash flow hedges, and as a result, all changes in the fair value are recognized in "Change in fair value of interest rate swaps" in the Consolidated Statements of Operations rather than through other comprehensive income. At September 30, 2016, we recorded a long-term asset of $44 thousand recorded in "Other assets" on our Consolidated Balance Sheets and a long-term liability of $809 thousand recorded in "Other long-term liabilities" on our Consolidated Balance Sheets, each representing the fair value of the interest rate swap agreements. The swaps were valued based on observable inputs for similar assets and liabilities and other observable inputs for interest rates and yield curves (Level 2 inputs).
New and recently adopted accounting standards [Policy Text Block]	New and Recently Adopted Accounting Standards In August 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-15, Statement of Cash Flows (Topic 230). This ASU is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. This new standard is effective for annual periods beginning after December 15, 2017, and interim periods within that reporting period. Early adoption is permitted, provided that all of the amendments are adopted in the same period. The guidance requires application using a retrospective transition method. We are evaluating the effect that this guidance will have on our consolidated statements of cash flows. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting. This ASU simplifies several aspects of the accounting for employee share-based payment transactions, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. This new standard is effective for annual periods beginning after December 15, 2016, and interim periods within that reporting period. Early adoption is permitted in any interim or annual period, with adjustments reflected as of the beginning of the fiscal year of adoption. We are evaluating the effect that this guidance will have on our consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU 2016-02, Leases. This amendment requires a lessee to recognize substantially all leases (whether operating or finance leases) on the balance sheet as a right-of-use asset and an associated lease liability. Short-term leases of 12 months or less are excluded from this amendment. For leases defined as finance leases under the new standard, the lessee subsequently recognizes interest expense and amortization of the right-of-use asset, similar to accounting for capital leases under current GAAP. For leases defined as operating leases under the new standard, the lessee subsequently recognizes straight-line lease expense over the life of the lease. This new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. The guidance is to be applied using a modified retrospective transition method with the option to elect a package of practical expedients. The adoption of this ASU will result in a significant increase to our balance sheet for lease liabilities and right-of-use assets, which has not yet been quantified. We are currently evaluating this and the other effects of this ASU on our financial statements. In July 2015, the FASB issued ASU 2015-11, Simplifying the Measurement of Inventory. This ASU requires entities to measure most inventory "at the lower of cost or net realizable value," thereby simplifying the current guidance under which an entity must measure inventory at the lower of cost or market. Although the new standard is not effective until annual and interim reporting periods beginning after December 15, 2016, early adoption is permitted. We do not expect the adoption of this guidance to have a material effect on our financial statements. In May 2015, the FASB issued ASU 2015-07, Fair Value Measurement (Topic 820): Disclosures of Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent). This ASU removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value per share practical expedient. This ASU also removes the requirement to make certain disclosures for all investments that are eligible to be measured at fair value using the net asset value per share practical expedient. Although we adopted the new standard on January 1, 2016, there was no effect on our interim reporting periods. The adoption of this standard will affect certain pension asset disclosures in our annual reporting period and will have no impact on our results of operations, financial position, or cash flows. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. This ASU requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in GAAP when it becomes effective. At its July 9, 2015, meeting, the FASB decided to delay the effective date of the revenue recognition standard by one year. The new standard is now effective for annual and interim reporting periods beginning after December 15, 2017. However, reporting entities may choose to adopt the standard as of the original effective date. The standard permits the use of either the retrospective or cumulative effect transition method. We are evaluating the effect that this guidance will have on our consolidated financial statements and related disclosures. We have not yet selected a transition method nor have we determined the effect of the standard on our financial statements. There were no other accounting standards recently issued that had or are expected to have a material impact on our consolidated financial statements and associated disclosures.
Compensation Related Costs [Policy Text Block]	We recognize stock awards with only service conditions on a straight-line basis over the requisite service period.

Disclosure of accounting policy for leasing arrangements (both lessor and lessee). This disclosure may address (1) lease classification (that is, operating versus capital), (2) how the term of a lease is determined (for example, the circumstances in which a renewal option is considered part of the lease term), (3) how rental revenue or expense is recognized for a lease that contains rent escalations, (4) an entity's accounting treatment for deferred rent, including that which arises from lease incentives, rent abatements, rent holidays, or tenant allowances (5) an entity's accounting treatment for contingent rental payments and (6) an entity's policy for reviewing, at least annually, the residual values of sales-type and direct-finance leases. The disclosure also may indicate how the entity accounts for its capital leases, leveraged leases or sale-leaseback transactions.