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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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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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

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

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Derivatives and Hedging Activities - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) Derivative	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) Derivative	Jun. 30, 2015 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Termination value of derivatives in net liability position	$ 32,100,000		$ 32,100,000
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Effective portion of change in fair value of cash flow hedges	(2,894,000)		$ (7,034,000)
Interest rate hedging exposure to variability in future cash flows for forecasted transactions, maximum period			20 years 3 months
Interest Rate Swap [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of interest rate swaps	$ 51,500,000		$ 51,500,000
Number of interest rate swaps \| Derivative	2		2
Interest Rate Swap [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Fair Value Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of interest rate swaps	$ 15,900,000		$ 15,900,000
Number of interest rate swaps \| Derivative	2		2
Interest Rate Swap [Member] \| Derivatives not Designated as Hedging Instruments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of interest rate swaps	$ 574,200,000		$ 574,200,000
Number of interest rate swaps \| Derivative	48		48
Gain (Loss) related to changes in fair value of swaps	$ (440,000)	$ 20,000	$ (792,000)	$ (86,000)
Interest Rate Products [Member] \| Derivatives Designated as Hedging Instruments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) related to changes in fair value of swaps	(1,000)	7,000	(2,000)	2,000
Interest Rate Products [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Effective portion of change in fair value of cash flow hedges	(2,894,000)		(7,034,000)
Interest Rate Products [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Fair Value Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) related to changes in fair value of swaps	137,000	(114,000)	329,000	(4,000)
Interest Rate Products [Member] \| Derivatives not Designated as Hedging Instruments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) related to changes in fair value of swaps	$ (440,000)	$ 20,000	$ (792,000)	$ (86,000)