Risk Management and Derivatives (Fair Value of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Designated as hedge
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	$ 0	$ 0
Derivative Liabilities, Fair Value	0	47
Designated as hedge | Foreign exchange contracts
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	0	0
Derivative Liabilities, Fair Value	0
Designated as hedge | Foreign exchange contracts | Other Liabilities
Derivative financial instruments on consolidated balance sheets
Derivative Liabilities, Fair Value		8
Designated as hedge | Interest rate swaps
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	0	0
Derivative Liabilities, Fair Value	0
Designated as hedge | Interest rate swaps | Other Liabilities
Derivative financial instruments on consolidated balance sheets
Derivative Liabilities, Fair Value		39
Not designated as hedge
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	0	727
Derivative Liabilities, Fair Value	0	0
Not designated as hedge | Foreign exchange contracts
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	0
Derivative Liabilities, Fair Value	0	0
Not designated as hedge | Foreign exchange contracts | Other Assets
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value		702
Not designated as hedge | Interest rate cap
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	0
Derivative Liabilities, Fair Value	$ 0	0
Not designated as hedge | Interest rate cap | Other Assets
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value		$ 25