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
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Average fixed interest rate related to the group of interest rate derivatives.

+ References

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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.

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Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

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- Definition

The net gain (loss) during the reporting period due to ineffectiveness in interest rate cash flow hedges. Recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Derivatives and Hedging Activities - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	May 31, 2017	Dec. 31, 2016
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Net loss on derivative instruments	$ (600,000)
Ineffective portion due to change in fair value of derivatives	0
Interest expense	174,059,000	$ 184,669,000
Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Notional value	1,200,000,000
Interest Rate Swap [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Interest expense	$ 3,000,000
Interest Rate Swap [Member] \| Subsequent Event [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Weighted average fixed rate of interest			1.844%
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member] \| Subsequent Event [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Notional value			$ 1,200,000,000
Interest Rate Swap [Member] \| LIBOR [Member] \| Minimum [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Variable rate of interest	0.75%			0.75%
Interest Rate Swap [Member] \| LIBOR [Member] \| Minimum [Member] \| Subsequent Event [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Variable rate of interest			0.00%