Defined Benefit Plan, Accumulated Benefit Obligation, Increase (Decrease) For Plan Amendment

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- Definition

Defined benefit plan unfunded benefit obligation.

+ References

No definition available.

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- Definition

Defined Contribution Plan, Employer Matching Contribution, Additional Percent of Match

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- Definition

Defined Contribution Plan, Initial Savings Rate

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No definition available.

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- Definition

Defined Contribution Plan, Period Of Employement For Eligibility

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- Definition

Minimum age for increase in per capita cost of health care benefit.

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No definition available.

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- Definition

Period of which the assumed health care cost trend rate is changing

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- Definition

Year of service who have reached fifty five years of age.

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No definition available.

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- Definition

Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation).

+ References

No definition available.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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- Definition

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

+ 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 (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 35
-Paragraph 123
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-URI http://asc.fasb.org/extlink&oid=64937487&loc=d3e36068-114959

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12551-114930

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-Name Accounting Standards Codification
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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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

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12355-114930

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6749337

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6520858

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

+ Details

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Health Care Cost Trend Rate
-URI http://asc.fasb.org/extlink&oid=6514820

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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-Publisher FASB
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-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920

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- Definition

The ultimate trend rate for health care costs.

+ References

+ 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

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

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Retirement Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Newly eligible associates initial savings rate		3.00%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		$ 1,132	$ 16,123
Funded status at end of year-net asset (liability)		50,521	36,274
Excess of plan assets over the benefit obligation		66,200
Unfunded benefit obligation		15,700
Estimated amounts of actuarial loss that will be amortized from AOCI into net periodic benefit cost over the next year		4,000
Pension assets		564,365	515,555	$ 491,550
Benefit obligation		$ 513,844	479,281	462,819
Hancock Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum age for increase in per capita cost of health care benefit		55 years
Years of credited service reaching 55 years of age		10 years
Increase (decrease) in pre- and post-medicare age health costs rate		8.00%
Period of assumed health rate decline		10 years
Decrease in ultimate rate over a period of time		5.00%
Whitney 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		$ 8,400	$ 7,700	$ 7,400
Minimum age for increase in per capita cost of health care benefit		55 years
Years of credited service reaching 55 years of age		10 years
Amended Hancock Pension Plan And 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation decreased	$ 17,300
Amended Hancock 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Period of employment for eligibility		3 years
Additional matching percentage	2.00%
First 1% Of Contribution Saved [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage		100.00%
Percentage of compensation saved		1.00%
Next 5% Of Contribution Saved [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage		50.00%
Percentage of compensation saved		5.00%
2% Of Contribution [Member] \| Amended Hancock 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage	2.00%
4% Of Contribution [Member] \| Amended Hancock 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage	4.00%
6% Of Contribution [Member] \| Amended Hancock 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage	6.00%