It represents multiemployer plans surcharge imposed.

No definition available.

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- Definition

It represents number of defined benefit pension plan.

+ References

No definition available.

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- Definition

Amount of contributions made by the employer to defined benefit plans.

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

- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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- Definition

The ultimate trend rate for health care costs.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of the obligation recognized by withdrawing from 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.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement and postemployment benefit plans.

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- Details

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PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Narrative) (Details)		12 Months Ended
	Jan. 01, 2027	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Number of defined benefit pension plans \| item		3
Multiemployer plans surcharge imposed		5.00%
Multiemployer plans, withdrawl obligation		$ 0
Defined benefit plan, ultimate health care cost trend rate		7.00%
Defined benefit plan, contributions by employer		$ 1,082,000	$ 0	$ 0
Defined benefit plans, estimated future employer contribution, next fiscal year		1,279,000
Defined contribution plan, employer discretionary contribution amount		2,244,000
Pension and other postretirement and postemployment benefit plans, noncurrent liabilities		$ 22,000	741,000
Cash and Cash Equivalents [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, target allocation percentage		5.00%
Marine Engineers Beneficial Association Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Multiemployer plans, withdrawl obligation			24,867,000
American Maritime Officers Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Multiemployer plans, withdrawl obligation					$ 21,891,000
United States Pension Plan of US Entity, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, contributions by employer		$ 1,082,000	$ 0
Scenario, Forecast [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, ultimate health care cost trend rate	4.75%
Minimum [Member] \| Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, target allocation percentage		55.00%
Minimum [Member] \| Fixed Income Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, target allocation percentage		25.00%
Maximum [Member] \| Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, target allocation percentage		75.00%
Maximum [Member] \| Fixed Income Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, target allocation percentage		45.00%