Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Tax loss carryforwards	$ 27,800
Unrepatriated foreign earnings	1,600
Domestic Tax Authority [Member]
Income Tax Disclosure [Line Items]
Total deferred tax assets	99,481	$ 101,556
Total deferred tax liabilities	54,112	19,025
Net deferred tax asset	45,369	82,531
Non-U.S. [Member]
Income Tax Disclosure [Line Items]
Total deferred tax assets	19,082	20,012
Total deferred tax liabilities	6,774	9,340
Net deferred tax asset	12,308	10,672
Noncurrent Assets [Member] | Domestic Tax Authority [Member]
Income Tax Disclosure [Line Items]
Accounts receivable	1,155	1,392
Inventories	1,193	897
Deferred compensation	7,533	6,714
Depreciation and amortization	2,786	10,323
Postretirement benefits	26,602	26,475
Tax loss carryforwards	1,760	2,682
Tax credit carryforwards	50,624	42,851
Other	7,828	10,222
Deferred tax assets before valuation allowance	99,481	101,556
Less: valuation allowance
Total deferred tax assets	99,481	101,556
Noncurrent Assets [Member] | Non-U.S. [Member]
Income Tax Disclosure [Line Items]
Accounts receivable	1,381	1,304
Inventories	1,868	1,750
Deferred compensation
Depreciation and amortization	5,030	4,882
Postretirement benefits	3,478	4,138
Tax loss carryforwards	26,084	27,134
Tax credit carryforwards	1,186	1,740
Other	2,876	3,503
Deferred tax assets before valuation allowance	41,903	44,451
Less: valuation allowance	(22,821)	(24,439)
Total deferred tax assets	19,082	20,012
Noncurrent Liabilities [Member] | Domestic Tax Authority [Member]
Income Tax Disclosure [Line Items]
Unrepatriated foreign earnings	1,602	1,157
Depreciation and amortization	43,156	10,309
Postretirement benefits
Deferred Gain	7,156	7,559
Branch losses subject to recapture
Other	2,198
Total deferred tax liabilities	54,112	19,025
Noncurrent Liabilities [Member] | Non-U.S. [Member]
Income Tax Disclosure [Line Items]
Unrepatriated foreign earnings
Depreciation and amortization	2,466	3,174
Postretirement benefits	1,411	2,003
Deferred Gain
Branch losses subject to recapture		918
Other	2,897	3,245
Total deferred tax liabilities	$ 6,774	$ 9,340