Long-Term Debt and Related Matters (Narrative - United Kingdom) (Details) £ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016 GBP (£)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding		$ 127,073	$ 165,000
NatWest Bank [Member] | Base Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.50%
NatWest Bank [Member] | Foreign Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	£ 1,500	1,852
Line of Credit Facility, Collateral	This credit facility supports the United Kingdom's working capital requirements and is collateralized by substantially all of the assets of its United Kingdom operations.
Line of Credit Facility, Description	A subsidiary of the Company has a credit facility with NatWest Bank for its United Kingdom operations that includes an overdraft availability of £1,500 pounds sterling (approximately $1,852 at December 31, 2016). This credit facility supports the United Kingdom's working capital requirements and is collateralized by substantially all of the assets of its United Kingdom operations
Line of Credit Facility, Interest Rate Description	. The interest rate on this facility is the financial institution's base rate plus 2.50%.
Line of Credit Facility, Covenant Terms	The United Kingdom loan agreements contain certain financial covenants that require the subsidiary to maintain senior interest and cash flow coverage ratios. The subsidiary was in compliance with these financial covenants at December 31, 2016 and 2015.
Line of Credit Facility, Amount Outstanding		0
Line of Credit Facility, Current Borrowing Capacity		1,650	$ 2,194
NatWest Bank Outstanding Guarantees [Member] | Foreign Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding		$ 202