The 401K Plan Employer Matching Contribution Vesting Period

No definition available.

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- Definition

The 401K Plan, Matching Component Requisite Service Period

+ References

No definition available.

+ Details

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- Definition

Represents the total fair value of assets under a deferred compensation arrangement.

+ References

No definition available.

+ Details

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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Retirement Plans - 401(k) Savings Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
401K Plan After January 1, 2016
Defined Contribution Plan Disclosure
Maximum employee contribution as a percent of covered compensation	50.00%
401K Plan After January 1, 2016 \| Minimum
Defined Contribution Plan Disclosure
Requisite years of service	1 year
401K Plan After January 1, 2016 \| Maximum
Defined Contribution Plan Disclosure
Maximum company contribution as a percent of covered compensation	5.00%
401K Plan Before January 1, 2016 \| Maximum
Defined Contribution Plan Disclosure
Matching contributions vesting period	5 years
TCF 401K Plan
Defined Contribution Plan Disclosure
Fair value of assets in the plan	$ 583.0
Contributions to the plan	12.3	$ 12.3	$ 12.3
TCF 401K Plan \| Common Stock
Defined Contribution Plan Disclosure
Fair value of assets in the plan	$ 194.0
TCF 401K Supplemental Plan
Defined Contribution Plan Disclosure
Maximum employee contribution as a percent of covered compensation	50.00%
Fair value of assets in the plan	$ 69.7	51.7
Contributions to the plan	1.2	1.3	$ 1.2
TCF 401K Supplemental Plan \| Common Stock
Defined Contribution Plan Disclosure
Fair value of assets in the plan	27.6	$ 23.0
Chemical 401K Plan
Defined Contribution Plan Disclosure
Contributions to the plan	$ 4.1
Chemical 401K Plan \| Maximum
Defined Contribution Plan Disclosure
Maximum company contribution as a percent of covered compensation	6.00%