Debt - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended													0 Months Ended	3 Months Ended		1 Months Ended	0 Months Ended	3 Months Ended		0 Months Ended		3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Year One	Dec. 31, 2013 Year Two	Dec. 31, 2013 There After	Dec. 31, 2013 Minimum Year One	Dec. 31, 2013 Maximum	Dec. 31, 2013 Maximum There After	Dec. 31, 2013 Average Year Two	Dec. 31, 2013 Base Rate Loans Minimum	Dec. 31, 2013 Base Rate Loans Maximum	Dec. 31, 2013 Eurodollar Loans Minimum	Dec. 31, 2013 Eurodollar Loans Maximum	Oct. 26, 2012 Credit Facility	Dec. 31, 2013 Credit Facility	Dec. 31, 2013 Term Loan	Feb. 28, 2007 Senior Notes	Oct. 26, 2012 Senior Notes Credit Agreement	Dec. 31, 2013 Senior Notes Credit Agreement	Oct. 26, 2012 Senior Notes Credit Facility	Oct. 26, 2012 Revolving Loans Credit Facility	Dec. 31, 2013 Revolving Loans Credit Facility	Dec. 31, 2013 Standby Letters of Credit	Dec. 31, 2013 Letter of Credit
Debt Instrument [Line Items]
Aggregate principal amount																	$ 110,000
Annual interest rate										0.75%	1.50%	1.75%	2.50%				9.00%
Line of credit facility, expiration date																	Feb. 01, 2015						Apr. 01, 2016	Apr. 01, 2017
Aggregate principal amount outstanding																		65,000
Redemption price percentage of principal amount																		102.25%
Net loss on debt retirement		(2,835)																	2,835
Call premium amount included in the debt retirement net loss																			1,463
Unamortized debt issuance cost included in the debt retirement net loss																			1,252
Other expenses included in the debt retirement net loss																			120
Line of credit facility maximum borrowing capacity																				85,000	25,000
Principal amount under the credit facility														60,000
Maturity period for the credit facility														5 years
Outstanding amount in connection with the issuance of letter of credit																					5,000
Letter of credit outstanding	4,791																					4,791	169
Letter of credit available																						20,209
Amortization of term loan, 2013																4,500
Amortization of term loan, 2014																6,000
Amortization of term loan, 2015																6,000
Amortization of term loan, 2016																6,000
Amortization of term loan, 2017																7,500
Amortization of term loan, thereafter																30,000
Leverage Ratio	0.97						3.00
Debt Service Coverage Ratio	6.24					2.00		2.50	2.25
Debt Service Coverage Ratio Commencing Date			Sep. 30, 2014	Sep. 29, 2015	Sep. 30, 2015
Debt issuance cost															$ 1,386
Percentage of Letter of credit outstanding																								105.00%