Derivative Instruments -Additional information about the financial statement effects related to our cash flow hedges (Details) - Jun. 30, 2014 - Cash Flow Hedging - Reclassification out of Accumulated Other Comprehensive Income [Member] - USD ($) $ in Thousands	Total	Total
Effects of derivative instruments
Amount of Gain Recognized in OCI on Derivatives (Effective Portion)	$ 124	$ 249
Interest expense Member
Effects of derivative instruments
Amount of Gain Recognized in OCI on Derivatives (Effective Portion)	$ 124	$ 249