Risk Management and Derivatives (Fair Value of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Derivative financial instruments on consolidated balance sheets
Expected amount related to cash flow hedge that will be reclassified over next twelve months	$ 1,000
Designated as hedge
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	3,669
Derivative Liabilities, Fair Value		$ 10,244
Designated as hedge \| Interest rate swaps \| Other assets
Derivative financial instruments on consolidated balance sheets
Derivative Assets, Fair Value	$ 3,669
Designated as hedge \| Interest rate swaps \| Other liabilities
Derivative financial instruments on consolidated balance sheets
Derivative Liabilities, Fair Value		$ 10,244

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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