Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended		1 Months Ended	6 Months Ended	12 Months Ended		6 Months Ended			6 Months Ended			6 Months Ended
	Dec. 31, 2012	Nov. 15, 2012	May 31, 2006 Ohio State Economic Development Revenue Bonds, series 2002-4 [Member]	Dec. 31, 2012 Ohio State Economic Development Revenue Bonds, series 2002-4 [Member]	Mar. 31, 2002 Ohio State Economic Development Revenue Bonds, series 2002-4 [Member]	Dec. 31, 2012 Letters of credit [Member]	Dec. 31, 2012 Minimum [Member]	Dec. 31, 2012 Minimum [Member] Libor Rate [Member]	Dec. 31, 2012 Minimum [Member] Bank Base Rate [Member]	Dec. 31, 2012 Maximum [Member]	Dec. 31, 2012 Maximum [Member] Libor Rate [Member]	Dec. 31, 2012 Maximum [Member] Bank Base Rate [Member]	Dec. 31, 2012 Revolving Credit Facility [Member]	Nov. 15, 2012 Revolving Credit Facility [Member]	Nov. 15, 2012 Acquisition Facility [Member]
Debt Instrument [Line Items]
Revolving line-of-credit facility		$ 65.0												$ 35.0	$ 30.0
Additional revolving credit loan	35
The Credit Facility expiry Date													Nov. 15, 2017
Amortization percentage	2.50%
Effective interest rate on outstanding borrowings under the Credit Facility	1.71%							1.25%	0.25%		2.00%	1.00%
Unused commitment fees							0.25%			0.375%
LIBOR plus	Outstanding borrowings under the Credit Facility bear interest, at the Company’s option, at either LIBOR, fixed for interest periods of one, two, three or six month periods, plus 1.25% to 2.00%, or at the bank’s base rate, as defined, plus 0.25% to 1.00%, based upon the Company’s Total Funded Debt/EBITDA Ratio, as defined. The Company is also required to pay commitment fees on unused portions of the Credit Facility ranging from 0.25% to 0.375%, based on the Company’s Total Funded Debt/EBITDA Ratio, as defined.
Current borrowings drawn against credit facility	0.5					0.5							14.0
Principal amount, including premium					2.9
Bonds issued, Interest rate				5.00%
Bonds issued, Interest rate				5.45%
Discount on bonds issued			0.2
Irrevocable letter of credit	$ 0.3