Property and Equipment (Schedule) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 162,822	$ 145,002
Less: Accumulated depreciation	(68,099)	(62,588)
Property and equipment, net	94,723	82,414
Land and building
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,109	6,277
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment, gross	31,120	33,985
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	106,037	89,307
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,687	3,603
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 13,869	$ 11,830