Derivatives and Hedging Activities (Outstanding Interest Rate Derivatives Designated as Cash Flow Hedges of Interest Rate Risk) (Details) - Designated as Hedging Instrument	Dec. 31, 2016 USD ($) Contract
Interest Rate Cap
Derivative
Number of Instruments | Contract	2
Derivative, Notional Amount | $	$ 50,000,000
Interest Rate Swap
Derivative
Number of Instruments | Contract	15
Derivative, Notional Amount | $	$ 850,000,000