Operating Segment Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Sep. 30, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 235,166	$ 224,573	$ 775,941	$ 721,162
Long-lived assets	600,993	503,694	600,993	503,694	527,979
U.S. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	188,524	187,746	634,900	636,780
Long-lived assets	394,875	309,223	394,875	309,223	317,887
Mexico [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	36,902	29,912	110,560	72,162
Long-lived assets	159,546	141,423	159,546	141,423	155,488
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	3,070	2,877	8,998	7,976
Long-lived assets	4,758	10,133	4,758	10,133	10,199
U.K. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	6,670	4,038	21,483	4,244
Long-lived assets	41,772	42,873	41,772	42,873	44,363
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 42	$ 42	$ 42	$ 42	$ 42