RETIREMENT AND POSTRETIREMENT BENEFIT PLANS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Components of total pension cost
Service cost	$ 5,426	$ 4,544	$ 16,275	$ 13,205
Interest cost	10,368	11,127	31,097	33,067
Expected return on plan assets	(14,688)	(14,323)	(44,059)	(43,061)
Amortization of prior service cost	(23)	(16)	(68)	(47)
Amortization of net loss	7,773	5,444	23,316	16,392
Defined benefit plans	8,856	6,776	26,561	19,556
Multi-employer plans	223	241	690	717
Defined contribution plans	2,435	2,137	7,032	6,327
Total pension cost	11,514	9,154	34,283	26,600
Voluntarily contribution to defined benefit plans in United States			53,277
Expected contribution to defined benefit plans in United States during the current fiscal year	$ 60,000		$ 60,000

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The employer's best estimate of total contributions, expected to be paid to the plan in the current fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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

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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.

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The increase in the fair value of plan assets from contributions made by the employer.

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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.

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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.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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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.

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

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Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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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.

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