Fair Value Measurements Available-For-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 88,761	$ 77,244
Gross Unrealized Gain	11,404	11,203
Gross Unrealized Loss	(780)	(38)
Available-for-sale securities	99,385	88,409
Domestic equity mutual funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	26,950	25,361
Gross Unrealized Gain	9,363	8,920
Gross Unrealized Loss	(353)	0
Available-for-sale securities	35,960	34,281
Foreign equity mutual funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,656	4,581
Gross Unrealized Gain	2,028	2,235
Gross Unrealized Loss	0	0
Available-for-sale securities	6,684	6,816
Bond mutual funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	21,810	16,391
Gross Unrealized Gain	0	2
Gross Unrealized Loss	(303)	(22)
Available-for-sale securities	21,507	16,371
Bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	31,511	29,074
Gross Unrealized Gain	13	46
Gross Unrealized Loss	(124)	(16)
Available-for-sale securities	31,400	29,104
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,834	1,837
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	0
Available-for-sale securities	$ 3,834	$ 1,837

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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