EMPLOYEE BENEFIT PLANS (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 item	Dec. 31, 2013 item	Dec. 31, 2012	Dec. 31, 2011 item
401(k) Plan
Non-elective contribution by employer as percentage of gross annual wages	3.00%
Matching contribution by employer (as a percent)	100.00%
Percentage of gross annual wages matched by employer	4.00%
Expense under the plan	$ 3.0	$ 2.9	$ 2.5
Employee Stock Ownership Plan ("ESOP")
Number of significant acquisitions completed	1	0		2

Represents the number of significant acquisitions completed during the period.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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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

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Details

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