Derivative Instruments and Hedging Activities (Tables)

12 Months Ended

Dec. 31, 2017

Derivative [Line Items]

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

The following table summarizes the notional amounts of the Company's outstanding interest rate swap and cap agreements as of December 31, 2017:

	Notional Amount
Interest rate swap contracts	$	75,000
Interest rate cap contracts	$	75,000