Derivative Financial Instruments - Recognized Gain (Loss) (Details) (Not Designated as Hedging Instrument, Interest Expense, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Interest Rate Swap
Derivative Instruments, Gain (Loss)
Net gain (loss) on change in the fair value of derivative financial instruments	$ 10,796	$ (7,578)	$ (562)
Interest Rate Cap
Derivative Instruments, Gain (Loss)
Net gain (loss) on change in the fair value of derivative financial instruments	$ 0	$ (89)	$ (294)