Employee Benefit Plans - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014 SERP_retirement_age	Dec. 31, 2013	Dec. 31, 2012
Compensation and Retirement Disclosure [Abstract]
Employers matching contribution	50.00%
Employees first contribution	6.00%
401(k) profit sharing plan, employers matching contribution amount	$ 1,000,000	$ 600,000	$ 300,000
SERP annual retirement benefits period	15 years
SERP retirement age	65
SERP target annual retirement benefit	300,000
SERP annual rate of return	7.00%
SERP present value of the amount owed	$ 3,600,000

Supplemental executive retirement plans annual rate of return.

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- Definition

Supplemental executive retirement plans obligation period.

+ References

No definition available.

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- Definition

Supplemental executive retirement plans retirement age.

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- Definition

Supplemental executive retirement plans target annual retirement benefit.

+ References

No definition available.

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 710

-SubTopic 10

-Section 30

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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No definition available.

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Percentage employer matches of the employee's percentage contribution matched.

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