Fair Values of Derivative Instruments on Condensed Consolidated Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Other assets
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 34	$ 72
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	0	6
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative financial instruments, Liability	15,007	13,392
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	34	72
Derivative financial instruments, Liability	15,007	13,392
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	0	6
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=56946850&loc=SL5624163-113959

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

+ References

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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=56946850&loc=SL5624163-113959

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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=56946850&loc=SL5624163-113959

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