Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Jun. 30, 2014	Feb. 20, 2015
Document Information [Line Items]
Entity Registrant Name	Customers Bancorp, Inc.
Entity Central Index Key	0001488813
Trading Symbol	CUBI
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2014
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float		$ 450,339,717
Voting Common Stock, Entity Common Stock, Shares Outstanding
Document Information [Line Items]
Entity Common Stock, Shares Outstanding			25,685,524
Class B Non-Voting Common Stock, Entity Common Stock, Shares Outstanding
Document Information [Line Items]
Entity Common Stock, Shares Outstanding			1,121,730