Pension And Other Postretirement Benefit Plans, Total Funding Deficit

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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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.

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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=49170846&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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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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- Definition

The amount of cash or cash equivalents contributed during the reporting period by the entity to fund its pension plans and its non-pension postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

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- Definition

The amount of pension and other (such as medical, dental and life insurance) postretirement benefit costs recognized during the period for (1) defined benefit plans (periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss) on assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments) and for (2) defined contribution plans (to the extent that a plan's defined contributions to an individual's account are to be made for periods in which that individual renders services, the net cost for a period is the contribution called for in that period; if a plan calls for contributions for periods after an individual retires or terminates, the estimated cost is accrued during the employee's service 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=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 3: 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=49170846&loc=d3e28014-114942

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Savings Plans And Multiemployer Pension Plans (Details) £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 GBP (£)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Sep. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Mar. 31, 2014 GBP (£)
United Kingdom Merchant Navy Officers Pension Fund [Member] \| Foreign Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Pension and other postretirement benefit expense					$ 19.4
United Kingdom Merchant Navy Ratings Pension Fund [Member] \| Foreign Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Pension and other postretirement benefit expense		$ 6.9	£ 4.5			$ 0.4
Pension and other postretirement benefit plans, total funding deficit								$ 491.7	£ 325.0
American Maritime Officers Pension Plan [Member] \| Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Multiemployer Plans, Withdrawal Obligation							$ 39.9
Pension and Other Postretirement Benefit Contributions	$ 1.4	1.1		$ 1.1
Seafarers Pension Plan [Member] \| Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Benefit Contributions	$ 1.9	1.6		1.5
SEACOR Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	75.00%
Deferred compensation obligation	$ 0.4	0.3
SEACOR Deferred Compensation Plan [Member] \| Deferred Bonus [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	100.00%
SEACOR Deferred Compensation Plan [Member] \| Restricted Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	100.00%
SEACOR Savings Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer Matching Contribution Percent of Employees' Gross Pay	3.50%
Defined Contribution Plan Contributions	$ 1.8	3.8		2.4
Other Defined Contribution Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan Contributions	$ 0.7	$ 0.7		$ 0.7