Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares of the Company's common stock	1,785,000
Options granted, vesting conditions	Most options granted since 2005 contain performance-based vesting conditions.
Outstanding restricted shares	377,725
Compensation expense	$ 1,041,000	$ 947,000	$ 569,000
Stock-based compensation expense related to stock options	0	97,000	216,000
Unrecognized compensation cost related to nonvested share	0
Options granted	0	0	0
Stock based compensation grants	0	0	0
Unearned compensation related to restricted stock	2,129,000	1,608,000	1,679,000
Non-Performance Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of non-performance based options, issued	0	0	0
Unrecognized compensation cost related to nonvested share	$ 0
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	5 years
Minimum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	3 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	10 years
Maximum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	5 years

Share based compensation arrangement by share based payment award award vesting terms description.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award options and restricted stock shares outstanding number.

+ References

No definition available.

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- Definition

Unearned stock based compensation expense.

+ References

No definition available.

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- Definition

The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Value, after forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 30

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6743629&loc=d3e3913-113898

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 30

-Section 35

-Paragraph 1

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- Definition

Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

+ References

No definition available.

+ Details

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ References

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