Share-Based Payments (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Share-based Compensation	$ 1,479	$ 1,014	$ 4,235	$ 3,332
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 532	$ 365	$ 1,524	$ 1,200
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)	$ 9.45	$ 10.50	$ 12.64	$ 7.21
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures (in Shares)	50,000	6,500	172,934	229,562
Description Of Restricted Stock Awards Granted Prior	Generally, the restrictions on the restricted stock units granted to employees prior to January 1, 2011 lapse at a rate of 50% on the three year anniversary and the remaining 50% on the fourth year anniversary. Restrictions on restricted stock units granted to employees after January 1, 2011 lapse at a rate of 25% each year.
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)			162,901	146,412
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)			$ 18.49	$ 13.24
Prior To January 1, 2011 [Member]
Percentage Of Lapse Rate On Restricted Stock Units Granted To Employees			50.00%
Remaining Percentage Of Lapse Rate On Restricted Stock Units Granted To Employees			50.00%
After January 1, 2011 [Member]
Percentage Of Lapse Rate On Restricted Stock Units Granted To Employees			25.00%