Debt and Financing Arrangements - Summary of Reconciliation of Debt (Detail) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Debt Instruments [Abstract]
Credit Agreement with Banks	$ 25,000,000	$ 45,000,000
Senior Notes under a Master Shelf Agreement	17,857,000	21,429,000
Capital Leases, described below	38,337,000	16,606,000
Total debt	81,194,000	83,035,000
Less: current portion of long-term debt	12,031,000	9,138,000
Long-term debt, less current portion	$ 69,163,000	$ 73,897,000