Indebtedness - Additional Information (Detail) (USD $)	6 Months Ended
Jun. 30, 2014 Contract	Jun. 30, 2013
Debt Instrument [Line Items]
Number of Interest rate swap contract outstanding	1
Losses in other comprehensive income expected to be reclassified to earnings	$ (59,000)
Duration of losses in other comprehensive income expected to be reclassified to earnings	12 months
Fixed interest rate for interest rate swap contract	3.39%	3.39%
Interest rate swap, start date	Mar. 30, 2011
Interest rate swap, termination date	Dec. 31, 2014
Maximum
Debt Instrument [Line Items]
Capacity to increase borrowings under credit agreement	64,057,000
Cash Flow Hedging \| Interest Rate Swap
Debt Instrument [Line Items]
Notional amount of interest rate swap	33,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Senior secured credit facility	200,000,000
Senior secured credit facility term	5 years
Revolving Credit Facility \| Accordion Feature
Debt Instrument [Line Items]
Senior secured credit facility	$ 100,000,000

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

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

No definition available.

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- Definition

Estimated period for the anticipated transfer of gain (loss), net, from accumulated other comprehensive income into earnings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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