ASU 2016-16, Decrease in long-term deferred charge

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from intra-entity transfer of asset within consolidated group. Excludes intra-entity transfer of inventory.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Newly Adopted Accounting Pronouncements (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Selling and Administrative Expenses \| Scenario, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net benefit cost (credit)	$ 5,974	$ 233
Other Expense, Net \| Scenario, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net benefit cost (credit)	$ 5,974	$ 233
Accounting Standards Update 2016-16
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ 94
ASU 2016-16, Increase (Decrease) in long-term deferred charge			1,281
Deferred Tax Asset, Intra-entity Transfer, Asset Other than Inventory			1,187
Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ 1,262