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Hedging Activities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Feb. 29, 2012 | Dec. 31, 2013 | Dec. 31, 2012 | Jun. 30, 2011
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Trust preferred securities | $ 32.0 |  |  |
Bank payment on corresponding notional amount fixed rate/ Basis for determining strike rate on purchased interest rate cap |  | 30-Day Libor rate |  |
Interest rate swap agreement maturity date | 2018-01 |  |  |
Fair value of Interest rate swap, record as liability |  | 0.3 | 1.1 |
Notional amount of sold interest rate cap |  |  |  | 100
Strike rate of sold interest rate cap in basis points above strike rate on purchased interest rate cap |  |  |  | 1.25%
Payments made under interest rate cap contracts |  | 0 |  |
Interest rate swap agreement [Member] |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Bank payment on corresponding notional amount fixed rate/ Basis for determining strike rate on purchased interest rate cap |  | 90-Day Libor Rate |  |
Trust preferred securities interest rate index |  | 90-Day Libor Rate |  |
Fixed spread added to the variable rate on our trust preferred securities | 218 |  |  |
Notional amounts of interest rate swap agreement and purchased interest rate cap | 32.0 |  |  |
Interest rate cap contracts [Member] |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Notional amounts of interest rate swap agreement and purchased interest rate cap |  |  |  | $ 100.0

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Debt instrument descriptions of variable rate basis. + References No definition available. + Details
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- Definition Fair value of interest rate swap agreement liability. + References No definition available. + Details
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- Definition Fixed spread added to the variable rate on our trust preferred securities. + References No definition available. + Details
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- Definition Hedging activities interest rate swap agreement maturity date. + References No definition available. + Details
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- Definition Notional amount of sold interest rate cap. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Payment made under interest rate cap contract. + References No definition available. + Details
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- Definition Trust preferred securities. + References No definition available. + Details
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- Definition Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract. + References No definition available. + Details
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- Definition The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + Details
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- Details
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