Derivative Financial Instruments (Schedule of Cash Flow Hedging Derivatives) (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Total Interest Rate Cap
Derivative [Line Items]
Derivative, notional amount	$ 190,000
Fair Value Asset (Liability)	12
Cash flow hedging \| Interest Rate Swap, $250 million, July 2019 \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	250,000
Fair Value Asset (Liability)	3,519
Cash flow hedging \| Interest Rate Swap, $275 million, August 2019 \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	275,000
Fair Value Asset (Liability)	4,480
Cash flow hedging \| Total Interest Rate Swaps \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	525,000
Fair Value Asset (Liability)	7,999
Cash flow hedging \| Interest Rate Cap $50 million Notional September 2017 Maturity \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	50,000
Fair Value Asset (Liability)	6
Cash flow hedging \| Interest Rate Cap $40 million Notional September 2017 Maturity \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	40,000
Fair Value Asset (Liability)	6
Cash flow hedging \| Total Interest Rate Cap \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	90,000
Fair Value Asset (Liability)	12
Cash flow hedging \| Interest rate swaps and caps \| Designated as hedging instrument
Derivative [Line Items]
Derivative, notional amount	615,000
Fair Value Asset (Liability)	$ 8,011

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

No definition available.

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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13495-108611

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