Property, Plant, and Equipment, Net (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2015	Sep. 30, 2014
Construction in progress	$ 216,021	$ 223,958
Property, Plant and Equipment, Net	688,336	513,279
Second Campus Rockford Illinois [Member]
Construction in progress	27,633	85,283
Capitalized interest	430	2,963
New Campus Fort Collins Colorado [Member]
Construction in progress	117,882	37,268
Capitalized interest	3,996	2,392
Building Site Niles Illinois [Member]
Construction in progress	4,960	55,629
Building and Building Improvements [Member] \| Second Campus Rockford Illinois [Member]
Contruction in progress placed into service	120,000
Buildings and improvements and Office furniture and equipment [Member] \| Building Site Niles Illinois [Member]
Contruction in progress placed into service	72,000
Assets Held-for-sale [Member] \| Land and Building [Member]
Property, Plant and Equipment, Net	$ 692	$ 2,465

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

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- Definition

Amount of reclassification, impairment, donation, or other change to long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230

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- Definition

The amount of interest that was capitalized on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

+ References

No definition available.

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