Fair Values of Derivative Instruments on Condensed Consolidated Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Other assets
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 132	$ 396
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	24	49
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative financial instruments, Liability	17,997	20,015
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	0	0
Parent Company [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	132	396
Derivative financial instruments, Liability	17,997	20,015
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	24	49
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	$ 0	$ 0

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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

+ References

+ Details

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- Definition

Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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