Derivative Financial Instruments (Schedule Of Cash Flow Hedging Instruments) (Detail) $ in Thousands	Sep. 30, 2016 USD ($)
Total Interest Rate Cap
Derivative [Line Items]
Notional amount	$ 265,000
Fair Value Asset (Liability)	18
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Swap, $25 million, October 2016
Derivative [Line Items]
Notional amount	25,000
Fair Value Asset (Liability)	(7)
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Swap, $250 million, July 2019
Derivative [Line Items]
Notional amount	250,000
Fair Value Asset (Liability)	106
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Swap, $275 million, August 2019
Derivative [Line Items]
Notional amount	275,000
Fair Value Asset (Liability)	426
Cash Flow Hedging \| Designated as Hedging Instrument \| Total Interest Rate Swap
Derivative [Line Items]
Notional amount	550,000
Fair Value Asset (Liability)	525
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Cap, $50 million, September 2017
Derivative [Line Items]
Notional amount	50,000
Fair Value Asset (Liability)	9
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Cap, $40 million, September 2017
Derivative [Line Items]
Notional amount	40,000
Fair Value Asset (Liability)	8
Cash Flow Hedging \| Designated as Hedging Instrument \| Total Interest Rate Cap
Derivative [Line Items]
Notional amount	90,000
Fair Value Asset (Liability)	17
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Swaps and Caps
Derivative [Line Items]
Notional amount	640,000
Fair Value Asset (Liability)	$ 542

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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- Definition

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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