Restructuring, Impairment and Other Costs - Restructuring and Executive Severance (Details) - Executive Severance - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Restructuring Reserve [Roll Forward]
Accrued beginning balance	$ 247
Costs Incurred	319	$ 711
Payments	(189)
Expenses/ Charges	0
Accrued end balance	$ 377

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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