EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS - Employee benefit plan amounts recognized in the Consolidated Balance Sheets and Consolidated Statements of Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 1,175us-gaap_DefinedBenefitPlanServiceCost	$ 1,041us-gaap_DefinedBenefitPlanServiceCost
Interest cost	550us-gaap_DefinedBenefitPlanInterestCost	620us-gaap_DefinedBenefitPlanInterestCost
Expected return on plan assets	(2,375)	(2,292)
Amortization of prior service cost	(100)	(103)
Defined Benefit Plan, Amortization of Gains (Losses)	450	481
Net periodic benefit cost (income)	$ (300)us-gaap_PensionExpense	$ (253)us-gaap_PensionExpense

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS - Employee benefit plan amounts recognized in the Consolidated Balance Sheets and Consolidated Statements of Income (Details) (USD $)
In Thousands, unless otherwise specified

3 Months Ended

Mar. 31, 2015

Mar. 31, 2014

Compensation and Retirement Disclosure [Abstract]

Service cost

$ 1,175us-gaap_DefinedBenefitPlanServiceCost

$ 1,041us-gaap_DefinedBenefitPlanServiceCost

Interest cost

550us-gaap_DefinedBenefitPlanInterestCost

620us-gaap_DefinedBenefitPlanInterestCost

Expected return on plan assets

(2,375)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets

(2,292)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets

Amortization of prior service cost

(100)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

(103)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

Defined Benefit Plan, Amortization of Gains (Losses)

450us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses

481us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses

Net periodic benefit cost (income)

$ (300)us-gaap_PensionExpense

$ (253)us-gaap_PensionExpense

- Details

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- Definition

The amount of gains or losses recognized in net periodic benefit cost.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

+ Details

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512136

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

+ Details

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the 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 (h)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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Balance Type:	debit
Period Type:	duration

- Definition

The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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Balance Type:	debit
Period Type:	duration