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Derivatives and Hedging Activities - Additional Information (Detail) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 USD ($) Contract | Sep. 30, 2015 USD ($) | Sep. 30, 2016 USD ($) Contract | Sep. 30, 2015 USD ($)
Credit Default Option [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Credit Risk Related Contingent Features Termination Value | $ 9,600,000 |  | $ 9,600,000 |
Net Liability Position [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Credit Risk Related Contingent Features Termination Value | 9,600,000 |  | 9,600,000 |
ERROR in label resolution. |  |  |  |
Derivative [Line Items] |  |  |  |
Fair Value of Credit Risk Derivatives | $ 9,000,000 |  | $ 9,000,000 |
Designated as Hedging Instrument [Member] | Interest Rate Caps |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Number of Instruments Held | Contract | 3 |  | 3 |
Derivative, Notional Amount | $ 75,000,000 |  | $ 75,000,000 |
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Number of Instruments Held | Contract | 7 |  | 7 |
Derivative, Notional Amount | $ 550,000,000 |  | $ 550,000,000 |
Designated as Hedging Instrument [Member] | Interest Expense |  |  |  |
Derivative [Line Items] |  |  |  |
Loss on Cash Flow Hedge Ineffectiveness | $ 96,000 | $ (44,000) | (67,000) | $ (117,000)
Change in fair value of interest rate derivatives included in AOCI and expected to be reclassified in the next 12 months |  |  | $ 2,600,000 |

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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 Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226003-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959 + Details
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