Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue out of scope of ASC 606	$ 77,623	$ (4,802)
Noninterest income	136,963	51,561
Fees and service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenue out of scope of ASC 606	2,985	24
Noninterest income	34,597	26,278
Wealth management revenue
Disaggregation of Revenue [Line Items]
Revenue out of scope of ASC 606	5,912	0
Noninterest income	6,151	0
Card and ATM revenue
Disaggregation of Revenue [Line Items]
Revenue out of scope of ASC 606	2,478	12
Noninterest income	21,685	18,659
Other noninterest income
Disaggregation of Revenue [Line Items]
Revenue out of scope of ASC 606	66,248	(4,838)
Noninterest income	74,530	6,624
Consumer Banking
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	53,459	46,505
Consumer Banking \| Fees and service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	30,218	25,193
Consumer Banking \| Wealth management revenue
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	239	0
Consumer Banking \| Card and ATM revenue
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	19,181	18,630
Consumer Banking \| Other noninterest income
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	3,821	2,682
Commercial Banking
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	3,384	5,904
Commercial Banking \| Fees and service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	1,394	1,061
Commercial Banking \| Wealth management revenue
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	0	0
Commercial Banking \| Card and ATM revenue
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	26	17
Commercial Banking \| Other noninterest income
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	1,964	4,826
Enterprise Services
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	2,497	3,954
Enterprise Services \| Fees and service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	0	0
Enterprise Services \| Wealth management revenue
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	0	0
Enterprise Services \| Card and ATM revenue
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	0	0
Enterprise Services \| Other noninterest income
Disaggregation of Revenue [Line Items]
Revenues within the scope of 606	$ 2,497	$ 3,954

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.

No definition available.

+ Details

Name:	us-gaap_DisaggregationOfRevenueLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

+ Details

Name:	us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue that is not accounted for under Topic 606.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

Name:	us-gaap_RevenueNotFromContractWithCustomer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_DepositAccountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_FiduciaryAndTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_CreditAndDebitCardMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_ProductAndServiceOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tcf_ConsumerBankingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tcf_CommercialBankingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tcf_EnterpriseServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: