Derivative Financial Instruments - Recurring Basis and Basis for Measurement (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets
Total Derivative Assets	$ 3,379	$ 1,087
Liabilities
Total Derivative Liabilities	33	57
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Total Derivative Assets	0	0
Liabilities
Total Derivative Liabilities	0	0
Significant Observable Inputs (Level 2)
Assets
Total Derivative Assets	3,379	1,087
Liabilities
Total Derivative Liabilities	33	57
Significant Unobservable Inputs (Level 3)
Assets
Total Derivative Assets	0	0
Liabilities
Total Derivative Liabilities	0	0
Forward Currency Contracts
Assets
Total Derivative Assets	186	26
Liabilities
Total Derivative Liabilities	33	57
Forward Currency Contracts | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Total Derivative Assets	0	0
Liabilities
Total Derivative Liabilities	0	0
Forward Currency Contracts | Significant Observable Inputs (Level 2)
Assets
Total Derivative Assets	186	26
Liabilities
Total Derivative Liabilities	33	57
Forward Currency Contracts | Significant Unobservable Inputs (Level 3)
Assets
Total Derivative Assets	0	0
Liabilities
Total Derivative Liabilities	0	0
Interest Rate Swap
Assets
Total Derivative Assets	3,193	1,061
Interest Rate Swap | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Total Derivative Assets	0	0
Interest Rate Swap | Significant Observable Inputs (Level 2)
Assets
Total Derivative Assets	3,193	1,061
Interest Rate Swap | Significant Unobservable Inputs (Level 3)
Assets
Total Derivative Assets	$ 0	$ 0