Debt (Details) (USD $)	9 Months Ended					3 Months Ended						3 Months Ended			3 Months Ended
	Jun. 30, 2012 Rate	May 15, 2012 New Credit Facility [Member]	Jun. 30, 2012 Revolving Loans New Credit Facility[Member]	May 15, 2012 Revolving Loans New Credit Facility[Member]	May 15, 2012 Revolving Loans Prior Credit Facility [Member]	Mar. 31, 2012 Term Loans Prior Credit Facility [Member]	Dec. 31, 2011 Term Loans Prior Credit Facility [Member]	Jul. 02, 2011 Term Loans Prior Credit Facility [Member]	Apr. 02, 2011 Term Loans Prior Credit Facility [Member]	Jan. 01, 2011 Term Loans Prior Credit Facility [Member]	Apr. 04, 2008 Term Loans Prior Credit Facility [Member]	Jun. 30, 2012 Term Loans New Credit Facility [Member]	May 15, 2012 Term Loans New Credit Facility [Member]	Jun. 30, 2012 Increase Option [Member]	Jul. 02, 2011 Senior Notes [Member] Rate	Jun. 30, 2012 Senior Notes [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity		$ 250,000,000		$ 160,000,000	$ 100,000,000
Credit facility outstanding at end of period						90,000,000		101,300,000			150,000,000	86,300,000	90,000,000
Line of Credit Facility, Maximum Borrowing Capacity			260,000,000											100,000,000
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	1.00%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Deferred Finance Costs, Net	900,000
Gains (Losses) on Extinguishment of Debt	200,000
Repayment on outstanding Credit Facility						3,750,000	3,750,000	3,750,000	3,750,000	3,750,000		3,750,000
Issuance of Senior Notes, principal amount															175,000,000
Debt Instrument, Interest Rate, Stated Percentage															5.20%
Senior Notes, principal outstanding															$ 175,000,000	$ 175,000,000