Business Acquisition, Equity Interest Issued or Issuable, Share Exchange Ratio

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Pending Merger with Chemical Financial Corporation - Pending Merger with Chemical Financial Corporation (Details) - USD ($) $ in Billions		12 Months Ended
	Jan. 28, 2019	Dec. 31, 2018	Dec. 31, 2017
Series C Preferred Stock
Pending Merger with Chemical Financial Corporation
Annual rate of dividend (as a percent)		5.70%	5.70%
Subsequent event \| Scenario, Forecast \| Chemical Common Stock
Pending Merger with Chemical Financial Corporation
Share conversion ratio	0.5081
Subsequent event \| Scenario, Forecast \| Series C Preferred Stock
Pending Merger with Chemical Financial Corporation
Annual rate of dividend (as a percent)	5.70%
Subsequent event \| Scenario, Forecast \| New Chemical Preferred Stock
Pending Merger with Chemical Financial Corporation
Share conversion ratio	1.0000
Subsequent event \| Chemical Financial Corporation \| Scenario, Forecast
Pending Merger with Chemical Financial Corporation
Assets of Chemical Financial Corporation	$ 21.5
Approximate ownership percentage of the combined company	46.00%
Subsequent event \| TCF Financial Corporation \| Scenario, Forecast
Pending Merger with Chemical Financial Corporation
Approximate ownership percentage of the combined company	54.00%