Fair Value Measurements - Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Company Owned Life Insurance	$ 1,544	$ 1,594
Assets, Fair Value Disclosure	1,544	1,594
Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Company Owned Life Insurance	0	0
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Company Owned Life Insurance	1,544	1,594
Assets, Fair Value Disclosure	1,544	1,594
Fair Value, Inputs, Level 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Company Owned Life Insurance	0	0
Assets, Fair Value Disclosure	$ 0	$ 0