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Long-Term Debt and Related Matters (Narrative - United States) (Details) $ / shares in Units, $ in Thousands |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Nov. 07, 2016 USD ($) | Jun. 29, 2016 USD ($) | Dec. 31, 2016 USD ($) $ / shares | Sep. 30, 2016 $ / shares | [2] | Jun. 30, 2016 $ / shares | [3] | Mar. 31, 2016 $ / shares | Dec. 31, 2015 USD ($) $ / shares | Sep. 30, 2015 $ / shares | [5] | Jun. 30, 2015 $ / shares | Mar. 31, 2015 $ / shares | Dec. 31, 2016 USD ($) $ / shares | Dec. 31, 2015 USD ($) $ / shares | Dec. 31, 2014 $ / shares
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loan payable in quarterly installments through January 1, 2020 with an interest rate of 3.92% at December 31, 2016 |  |  | $ 30,000 |  |  |  |  | $ 0 |  |  |  |  | $ 30,000 | $ 0 |
Dividends paid per common share | $ / shares |  |  | $ 0 | [1] | $ 0.04 | $ 0.04 | $ 0.04 | $ 0.04 | [4] | $ 0.04 | $ 0.04 | $ 0.04 | $ 0.12 | $ 0.16 | $ 0.13
Line of Credit Facility, Amount Outstanding |  |  | $ 127,073 |  |  |  |  | $ 165,000 |  |  |  |  | $ 127,073 | $ 165,000 |
Letter of Credit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Amount Outstanding |  |  | $ 425 |  |  |  |  | $ 526 |  |  |  |  | $ 425 | $ 526 |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 195,000 | $ 275,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Interest Rate Description | The Second Amendment provides for the elimination of the three lowest tiers of the pricing grid that had previously been defined in the First Amendment. Upon execution of the Second Amendment through the quarter ended March 31, 2018, the Company will be locked into the highest tier of the pricing grid which provides for pricing of the prime rate plus 225 basis points on base rate loans and the applicable LIBOR rate plus 325 basis points on euro rate loans. For each quarter after March 31, 2018 and through the maturity date of the credit facility, the Company's position on the pricing grid will be governed by a Minimum Net Leverage ratio which is the ratio of Consolidated Indebtedness less cash on hand in excess of $15,000 to EBITDA. If, after March 31, 2018 the Minimum Net Leverage ratio positions the Company on the lowest tier of the pricing grid, pricing will be the prime rate plus 150 basis points on base rate loans or the applicable LIBOR rate plus 250 basis points on euro rate loans. |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Restrictive Covenants | The Second Amendment further provides for modifications to the financial covenants as defined in the Amended and Restated Credit Agreement. The Second Amendment calls for the elimination of the Maximum Leverage Ratio covenant through the quarter ended June 30, 2018. After that period, the Maximum Gross Leverage Ratio covenant will be reinstated to require a maximum ratio of 4.25 Consolidated Indebtedness to 1.00 Gross Leverage for the quarter ended September 30, 2018, and 3.75 to 1.00 for all periods thereafter until the maturity date of the credit facility. The Second Amendment also includes a Minimum Last Twelve Months EBITDA covenant ("Minimum EBITDA"). For the quarter ending December 31, 2016 through the quarter ending June 30, 2017, the Minimum EBITDA must be at least $18,500. For each quarter thereafter, through the quarter ended June 30, 2018, the Minimum EBITDA requirement will increase by various increments. At June 30, 2018, the Minimum EBITDA requirement will be $31,000. After the quarter ended June 30, 2018, the Minimum EBITDA covenant will be eliminated through the maturity of the credit agreement. The Second Amendment also includes a Minimum Fixed Charge Coverage Ratio covenant. The covenant represents the ratio of the Company's fixed charges to the last twelve months of EBITDA, and is required to be a minimum of 1.00 to 1.00 through the quarter ended December 31, 2017 and 1.25 to 1.00 for each quarter thereafter through the maturity of the credit facility. The final financial covenant included in the Second Amendment is a Minimum Liquidity covenant which calls for a minimum of $25,000 in undrawn availability on the revolving credit loan at all times through the quarter ended June 30, 2018.The Second Amendment includes several changes to certain non-financial covenants as defined in the Credit Agreement. Through the maturity date of the loan, the Company is now prohibited from making any future acquisitions. The limitation on permitted annual distributions of dividends or redemptions of the Company's stock has been decreased from $4,000 to $1,700. The aggregate limitation on loans to and investments in non-loan parties was decreased from $10,000 to $5,000. Furthermore, the limitation on asset sales has been decreased from $25,000 annually with a carryover of up to $15,000 from the prior year to $25,000 in the aggregate through the maturity date of the credit facility. |  |  |  |  |  |  |  |  |  |  |  |  |  |
Leverage ratio in effect for the seventh quarter of a credit agreement | 4.25 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Leverage ratio in effect for the eighth quarter and remainder of a credit agreement | 3.75 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum dividends, distributions, or redemptions allowed | $ 1,700 | 4,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Loans and advances limit | 5,000 | 10,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum asset sales allowed | $ 25,000 | 25,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Carryover of asset sales allowed |  | $ 15,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Dividend Restrictions | The limitation on permitted annual distributions of dividends or redemptions of the Company's stock has been decreased from $4,000 to $1,700. |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Covenant Compliance |  |  |  |  |  |  |  |  |  |  |  |  | At December 31, 2016, the Company was in compliance with the covenants in the Second Amendment. |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
EBITDA required | $ 18,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |
EBITDA required for seventh quarter | $ 31,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed charge coverage ratio | 1.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed charge coverage ratio after fifth quarter | 1.25 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Liquidity covenant | $ 25,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] | Euro-rate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 3.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] | Base Rate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 2.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] | Base Rate [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] | Base Rate [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 2.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company [Member] | Term loan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loan payable in quarterly installments through January 1, 2020 with an interest rate of 3.92% at December 31, 2016 | $ 30,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Maturity Date | Jan. 01, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | Fourth quarter 2016 includes deferred U.S. income taxes and foreign withholding taxes of $7,932 on unremitted foreign earnings and a valuation allowance of $29,719 against deferred tax assets.
[2] | Third quarter 2016 includes $6,946
[3] | Second quarter 2016 includes $128,938 impairment of assets related to the Chemtec, Protective Coatings, IOS and Rail Technologies product groups.
[4] | Fourth quarter 2015 includes $2,279 pre-tax gain on sale of Tucson, AZ concrete tie facility.
[5] | Third quarter 2015 includes $80,337 impairment of goodwill related to the IOS and Chemtec reporting units.

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