Derivative Financial Instruments (Schedule Of Cash Flow Hedging Instruments) (Detail) - Cash Flow Hedging - Designated as Hedging Instrument	Sep. 30, 2018 USD ($)
June 2019
Derivative [Line Items]
Notional Amount	$ 200,000,000
Fair Value Asset (Liability)	1,445,000
July 2019
Derivative [Line Items]
Notional Amount	250,000,000
Fair Value Asset (Liability)	3,275,000
August 2019
Derivative [Line Items]
Notional Amount	275,000,000
Fair Value Asset (Liability)	4,399,000
January 2020
Derivative [Line Items]
Notional Amount	175,000,000
Fair Value Asset (Liability)	1,554,000
January 2020
Derivative [Line Items]
Notional Amount	25,000,000
Fair Value Asset (Liability)	222,000
April 2020
Derivative [Line Items]
Notional Amount	50,000,000
Fair Value Asset (Liability)	317,000
April 2020
Derivative [Line Items]
Notional Amount	200,000,000
Fair Value Asset (Liability)	1,267,000
June 2020
Derivative [Line Items]
Notional Amount	200,000,000
Fair Value Asset (Liability)	3,741,000
September 2023
Derivative [Line Items]
Notional Amount	150,000,000
Fair Value Asset (Liability)	51,000
Total Cash Flow Hedges
Derivative [Line Items]
Notional Amount	1,525,000,000
Fair Value Asset (Liability)	$ 16,271,000

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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=77997519&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=77997519&loc=d3e13495-108611

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