Loans - Schedule of Carrying Amount of Loans Acquired under ASC Topic 310-10 (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Loans [Line Items]
Contractually required principal and interest at acquisition	$ 87,001
Nonaccretable difference (expected losses and foregone interest)	(6,478)
Cash flows expected to be collected at acquisition	80,523
Fair value of acquired loans at acquisition	66,675
Asc 310-10 Loan [Member]
Loans [Line Items]
Contractually required principal and interest at acquisition	1,224,635
Nonaccretable difference (expected losses and foregone interest)	(20,790)
Cash flows expected to be collected at acquisition	1,203,845
Fair value of acquired loans at acquisition	$ 1,014,903

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Fair value at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

+ Details

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- Definition

Amount of cash flows expected to be collected at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

+ References

+ Details

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- Definition

Amount of contractually required payments receivable at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

+ References

+ Details

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- Definition

The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

No definition available.

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