Retirement Plans (Defined Contribution Plans) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	$ 262	$ 629	$ 1,734	$ 2,369
UNITED STATES
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	152	413	1,289	1,842
CANADA
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	46	54	164	167
UNITED KINGDOM
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	$ 64	$ 162	$ 281	$ 360