Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 8,407	$ 8,924	$ 7,040
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	10 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	12 years
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	10 years
Customer And Renewal Lists [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	8 years
Customer And Renewal Lists [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	12 years
Other Intangible Assets [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	8 years
Other Intangible Assets [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization period of intangible assets, years	12 years