Carrying value of ACI commercial real estate loans at which discount is no longer being accreted

No definition available.

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- Definition

The carrying amount of commercial and commercial real estate ACI loans that are contractually delinquent in excess of 90 days but still classified as accruing loans due to discount accretion.

+ References

No definition available.

+ Details

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- Definition

Financing receivable credit quality indicator, the value at which relationships are reevaluated at least annually.

+ References

No definition available.

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- Definition

Maximum percent of one to four single family residential loans of any state not otherwise disclosed.

+ References

No definition available.

+ Details

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- Definition

Net pretax impact on earnings from loans sold.

+ References

No definition available.

+ Details

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- Definition

Percent of loans net of premiums, discounts and deferred fees and costs, covered and non-covered.

+ References

No definition available.

+ Details

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- Definition

Recorded investment in loans sold

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Amount of unpaid principal balance of ACI loans

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The unpaid principal balance of pledged real estate loans.

+ References

No definition available.

+ Details

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- Definition

The value of 1-4 single family residential and home equity ACI loans that are contractually delinquent by more than 90 days and accounted for in pools that are on accrual status.

+ References

No definition available.

+ Details

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- Definition

Unpaid principal balance of ACI loans sold

+ References

No definition available.

+ Details

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- Definition

The net investment in direct financing leases as of the balance sheet date consisting of: (a) minimum lease payments due on direct financing leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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- Definition

The effect of a change in method or methods for calculating the allowance for credit losses on the current period provision.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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Balance Type:	credit
Period Type:	duration

- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5111-111524

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. 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 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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- Definition

The cash outflow associated with purchasing loans held for investment purposes during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)(1)(i)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

+ Details

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Period Type:	instant

- Definition

The cash inflow associated with the sale of loans receivables arising from the financing of goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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Loans and Allowance for Loan and Lease Losses (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable Investment Past Due [Line Items]
Capital Leases, Net Investment in Direct Financing Leases	$ 458,182,000	$ 340,362,000
Unpaid principal balance of ACI loans	2,600,000,000bku_UnpaidPrincipalBalanceOfAciLoans	3,300,000,000bku_UnpaidPrincipalBalanceOfAciLoans
Purchases of loans	955,995,000	1,141,808,000	709,388,000
Unpaid principal balance of real estate loans pledged as security for FHLB advances	6,900,000,000
Unpaid principal balance of real estate loans pledged as security for FHLB advances	5,500,000,000
Unpaid principal balance of loans sold from pool of ACI loans with zero carrying value	50,000,000	102,000,000	73,000,000
Financing Receivable, Allowance for Credit Losses, Period Increase (Decrease)	10,000,000
Financing receivable credit quality indicator, the value at which relationships are reevaluated at least annually	1,000,000
Carrying value of 1-4 single family residential and home equity ACI loans delinquent more than 90 days and on accrual status	23,000,000	60,000,000
Carrying value of commercial and commercial real estate ACI loans that are delinquent more than 90 days and on accrual status		18,000,000
Maximum percent of one to four single family residential loans of any state not otherwise disclosed (in Percent) (more than)	5.00%
1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Recorded investment in loans sold	144,231,000	82,160,000	103,127,000
Cash proceeds, net of transaction costs	177,560,000	116,611,000	103,796,000
Net pretax impact on earnings from loans sold	33,329,000	34,451,000	669,000
Percent of loans net of premiums, discounts and deferred fees and costs, covered and non-covered (in Percent)	100.00%	100.00%
Commercial
Financing Receivable Investment Past Due [Line Items]
Recorded investment in loans sold	83,052,000
Cash proceeds, net of transaction costs	101,023,000
Commercial \| FLORIDA
Financing Receivable Investment Past Due [Line Items]
Percent of loans net of premiums, discounts and deferred fees and costs, covered and non-covered (in Percent)	48.30%
Commercial \| New York
Financing Receivable Investment Past Due [Line Items]
Percent of loans net of premiums, discounts and deferred fees and costs, covered and non-covered (in Percent)	36.60%
New Loans
Financing Receivable Investment Past Due [Line Items]
Non-covered loans, gross	11,230,392,000	7,514,113,000
New Loans \| Commercial finance subsidiaries
Financing Receivable Investment Past Due [Line Items]
Non-covered loans, gross	1,456,751,000	952,050,000
New Loans \| 1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Non-covered loans, gross	2,486,272,000	1,800,332,000
Purchases of loans	921,000,000	1,100,000,000
New Loans \| Consumer
Financing Receivable Investment Past Due [Line Items]
Non-covered loans, gross	26,293,000	213,107,000
Recorded investment in loans sold	302,800,000
New Loans \| Commercial
Financing Receivable Investment Past Due [Line Items]
Non-covered loans, gross	8,716,000,000	5,499,139,000
ACI loans \| Commercial real estate
Financing Receivable Investment Past Due [Line Items]
Carrying value of ACI commercial real estate loans at which discount is no longer being accreted		1,000,000
New and Non-ACI loans
Financing Receivable Investment Past Due [Line Items]
Loans 90 days past due and still accruing	$ 0	$ 500,000