Goodwill and Other Amortizing Intangible Assets - Summarized Other Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 23,454	$ 22,470
Accumulated Amortization	(21,789)	(21,159)
Net Intangible Assets	1,665us-gaap_FiniteLivedIntangibleAssetsNet	1,311us-gaap_FiniteLivedIntangibleAssetsNet
Customer Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	22,470	22,470
Accumulated Amortization	(21,773)	(21,159)
Net Intangible Assets	697	1,311
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	984	0
Accumulated Amortization	(16)	0
Net Intangible Assets	$ 968	$ 0

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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