Document And Entity Information	12 Months Ended
	Dec. 31, 2011	Mar. 16, 2012 Common Class A [Member]	Mar. 16, 2012 Common Class B [Member]
Entity Information [Line Items]
Entity Registrant Name	Customers Bancorp, Inc.
Entity Central Index Key	0001488813
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	FY
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2011
Entity Common Stock, Shares Outstanding		8,503,541	2,884,142