Operating Segment Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 277,126	$ 248,873
Long-lived assets	603,349	317,344	527,979
U.S. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	224,756	225,715
Long-lived assets	391,169	283,462	317,887
Mexico [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	40,245	19,421
Long-lived assets	158,073	23,899	155,488
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	4,814	3,661
Long-lived assets	9,658	9,745	10,199
U.K. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	7,311	76
Long-lived assets	44,407	238	44,363
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 42	$ 0	$ 42