Income Taxes - Deferred Tax Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Retirement benefits	$ 8,236	$ 9,621
Allowance for doubtful accounts	1,925	2,367
Insurance and litigation reserves	707	787
Postretirement benefits	1,623	1,863
Supplemental retirement benefits	3,670	3,220
Performance incentives	5,197	4,777
Equity-based compensation	2,088	1,823
Insurance settlement	7,755	8,100
Operating loss carryforward	7,343	7,815
Uncertain tax positions	(101)	2,785
Restructuring	217	1,897
Other	2,834	2,402
Deferred Tax Assets, Gross, Total	41,494	47,457
Valuation allowance	(6,344)	(6,259)
Total deferred income tax assets, net	35,150	41,198
Depreciation	5,709	5,924
Europe Pension and Other	1,055	1,107
Amortization and other	16,012	14,318
Total deferred income tax liabilities	$ 22,776	$ 21,349