Long-term Debt and Financing Arrangements - Additional Information (Detail)		6 Months Ended
	Feb. 18, 2014 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2014	Feb. 20, 2014 USD ($)
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 100,000,000		$ 100,000,000
Line of credit facility maximum borrowing capacity increased value	$ 100,000,000
Line of credit facility maximum borrowing capacity possible value of increase	50,000,000
Credit facility fixed charge coverage ratio		2.0
Required consolidated leverage ratio as of end of each fiscal quarter		3.0
Required Consolidated EBITDA		$ 30,000,000.0
Line of credit facility, remaining borrowing capacity		57,700,000
Standby letters of credit, outstanding		$ 2,300,000
Debt, Weighted Average Interest Rate		1.40%	1.50%
Federal Funds Effective Swap Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Eurocurrency Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Minimum [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	35,000,000
Minimum [Member] | Eurocurrency Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.75%
Maximum [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	100,000,000
Maximum [Member] | Eurocurrency Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%
Domestic Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 35,000,000.0