Retirement Plans (Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 Participant	Apr. 30, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Newly eligible associates initial savings rate	3.00%
Eligible participants under VERIP \| Participant	260
Pension plan assets		$ 808
Benefit obligation		$ 597
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 benefit pension plan eligible participants under voluntary early retirement incentive program.

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- Definition

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

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- Definition

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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921

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Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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