Share-Based Compensation (Adjustments for Change in Attribution Method - Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2013
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Pre-forfeiture share-based compensation expense	$ (800)
Pre-forfeiture share-based compensation expense, net of tax	(500)
Retained earnings	1,263,464	$ 1,209,197
Increase in additional paid in capital	1,794,665	1,765,595
Decrease in deferred tax liabilities	$ 40,621	69,610
Change in Attribution Method
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Retained earnings		(18,312)	$ (21,100)
Increase in additional paid in capital		24,428	29,100
Decrease in deferred tax liabilities		$ (6,116)	$ (8,000)

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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(30)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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