Related Party Transactions (Detail) (USD $)	3 Months Ended		9 Months Ended					3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2013 Management [Member] Related Customer [Member]	Sep. 30, 2012 Management [Member] Related Customer [Member]	Sep. 30, 2013 Management [Member] Related Customer [Member]	Sep. 30, 2012 Management [Member] Related Customer [Member]	Dec. 31, 2012 Management [Member] Related Customer [Member]	Sep. 30, 2013 Management [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Dec. 31, 2012 Management [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2013 Board of Directors Chairman [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2012 Board of Directors Chairman [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2013 Board of Directors Chairman [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2012 Board of Directors Chairman [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Oct. 16, 2013 Board of Directors Chairman [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member] Scenario, Forecast [Member] Subsequent Event [Member] Maximum [Member]	Sep. 30, 2013 Chief Executive Officer [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2012 Chief Executive Officer [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2013 Chief Executive Officer [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]	Sep. 30, 2012 Chief Executive Officer [Member] Life Insurance [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]
Related Party Transaction [Line Items]
Charges to related party	$ 135,000	$ 123,000	$ 422,000	$ 382,000
Due from related party	45,000		45,000		907,000
Revenue, related party	350,000	318,000	951,000	924,000
Accounts receivable, related party	414,000		414,000		1,232,000
Life insurance, face amount												200,000,000
Payments for life insurance policies								1,100,000	0	1,200,000	300,000		0	0	0	0
Carrying amount, life insurance policies						$ 10,100,000	$ 8,700,000