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Intangible Assets and Goodwill - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items] |
Weighted-average life | 6 years 6 months
Customer Related Intangibles [Member] |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average life | 8 years 9 months 18 days
Core Deposit Intangibles [Member] |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average life | 5 years 10 months 24 days
Mortgage Servicing Intangibles [Member] |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average life | 2 years 3 months 18 days

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- Details
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Balance Type: | na
Period Type: | duration

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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Period Type: | duration

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |