Operating Segment Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 241,380	$ 235,166	$ 770,437	$ 775,941
U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	184,396	188,524	612,261	634,900
Mexico
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	49,055	36,902	135,423	110,560
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	3,361	3,070	10,021	8,998
U.K.
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 4,568	$ 6,670	$ 12,732	$ 21,483