Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

Name:	us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Basis of Presentation and Summary of Significant Accounting Policies (Details) $ in Millions		6 Months Ended
	Jan. 02, 2020 USD ($)	Jun. 30, 2020 center office
Accounting Policies [Abstract]
Number of offices \| office		17
Business Acquisition [Line Items]
Number of mortgage loan production office		1
Metro Detroit
Business Acquisition [Line Items]
Number of banking centers		11
Grand Rapids
Business Acquisition [Line Items]
Number of banking centers		1
Jackson
Business Acquisition [Line Items]
Number of banking centers		1
Ann Arbor
Business Acquisition [Line Items]
Number of banking centers		3
Ann Arbor Bancorp, Inc
Business Acquisition [Line Items]
Total cash consideration \| $	$ 67.9