Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2011
Impaired Intangible Assets [Abstract]
Goodwill	$ 44,871,000	$ 44,871,000	$ 44,668,000
Other Intangible assets	31,833,000	31,833,000	33,050,000
Amortization expense for intangible assets	652,000	1,929,000
Estimated amortization expense for intangible assets for remainder year	632,000	632,000
Estimated amortization expense for intangible assets for year two	2,527,000	2,527,000
Estimated amortization expense for intangible assets for year three	2,527,000	2,527,000
Estimated amortization expense for intangible assets for year four	2,527,000	2,527,000
Estimated amortization expense for intangible assets for year five	2,503,000	2,503,000
Estimated amortization expense for intangible assets for year six	2,261,000	2,261,000
Estimated amortization expense for intangible assets thereafter	$ 1,483,000	$ 1,483,000