Employee Benefit Plans - Narrative (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended						3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Minimum	Mar. 31, 2013 Maximum	Mar. 31, 2013 Other Postretirement Benefits plan	Oct. 31, 2011 Western Conference of Teamsters Pension Plan	Mar. 31, 2013 Labor Management Pension Fund	Dec. 31, 2011 Labor Management Pension Fund	Dec. 31, 2012 Labor Management Pension Fund quarter
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Withdrawal obligation						$ 0			$ 4.3
Quarterly installment payments on estimated withdrawal liability								0.1
Number of quarters relating to installment payments on estimated withdrawal liability									80
Determination period relating to withdrawal liability							24 months
Number of non-pension multiemployer plans that the Company participates in					5
Hours required for plan qualification			1000 hours
Elective employee contribution, as a percentage of their annual pay, range			1.00%	100.00%
Percentage of employee contribution eligible for Company matching	50.00%
Company contribution, maximum percentage of employee's eligible income	6.00%
Plan periodic vesting percentage	20.00%
Plan, periodic vesting period	5 years
Automatic vesting age	65 years
Current employees, percent vested	100.00%
Matching contributions recorded by Company	$ 0.8	$ 0.9