Amounts paid to related parties and their affiliates for products or services.

No definition available.

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Namespace Prefix:	cubi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Benchmark percentage of aggregate assets for related party transactions

+ References

No definition available.

+ Details

Name:	cubi_BenchmarkPercentageOfAggregateAssetsForRelatedPartyTransactions
Namespace Prefix:	cubi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Benchmark percentage of gross revenues for related party transactions.

+ References

No definition available.

+ Details

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Namespace Prefix:	cubi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage ownership of related parties in their affiliates.

+ References

No definition available.

+ Details

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Namespace Prefix:	cubi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of participation in equity.

+ References

No definition available.

+ Details

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Namespace Prefix:	cubi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of deposits held by the entity for a related party (entity, shareholder, employee).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_UnfundedLoanCommitmentMember
Namespace Prefix:
Data Type:	na
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Transactions with Executive Officers, Directors, and Principal Shareholders - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Percentage of gross revenue	5.00%
Percentage of aggregate amount of consolidated assets	5.00%
Related party deposits	$ 14,000,000	$ 11,700,000
Director \| Jaxxon Promotions, Inc.
Related Party Transaction [Line Items]
Amount paid to related party	$ 27,300	$ 46,900	$ 45,800
Percentage of shareholding by director	25.00%
Minimum
Related Party Transaction [Line Items]
Percentage of participation in equity	10.00%
Line of Credit \| Affiliated Entity
Related Party Transaction [Line Items]
Available credit line	$ 1,800,000.0
Unfunded Loan Commitment \| Affiliated Entity
Related Party Transaction [Line Items]
Commitment to provide short-term commercial real estate financing	$ 8,000,000