Retirement Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2019	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Contributed to pension plan	$ 100
Newly eligible associates initial savings rate		3.00%
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%
Amended Hancock 401K Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Additional matching percentage		2.00%
Period of employment for eligibility		3 years
Amended Hancock 401K Plan [Member] \| 4% Of Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage		4.00%
Amended Hancock 401K Plan [Member] \| 6% Of Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage		6.00%
Amended Hancock 401K Plan [Member] \| 2% Of Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching percentage		2.00%

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

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- Definition

Defined Contribution Plan, Initial Savings Rate

+ References

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+ Details

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- Definition

Defined contribution plan, period of employment for eligibility.

+ 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

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

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

+ References

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- Definition

Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585

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