Employee Benefit Plans - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2014
Compensation And Retirement Disclosure [Abstract]
Retirement benefits based on years of service and compensation		5 years
Expected cash contribution		$ 320,000
Benefit payments from Restoration Plan		59,000
Defined benefit plan, expected additional contribution		54,000
Termination liability	$ 14,000,000

Defined benefit plan expected additional contribution.

No definition available.

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- Definition

Retirement benefits based on period of service and compensation.

+ References

No definition available.

+ Details

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- Details

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- Definition

If applicable, the cost of providing special or contractual termination benefits recognized during the period on the projected benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (q)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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