Face (par) amount of debt instrument at time of issuance.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 55
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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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- References

No definition available.

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Period Type:	duration

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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Subsequent Events (Details) - USD ($) $ in Thousands	Oct. 08, 2019	Oct. 01, 2019	Sep. 30, 2019
5.00% Monthly Senior Notes, Series 2010A, due 2040 [Member]
Subsequent Events [Abstract]
Interest rate			5.00%
4.75% York County Industrial Development Authority Revenue Bonds, Series 2006, due 2036 [Member]
Subsequent Events [Abstract]
Interest rate			4.75%
4.50% Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2014, due 2038 [Member]
Subsequent Events [Abstract]
Interest rate			4.50%
Subsequent Event [Member] \| 3.23% Senior Notes, due 2040 [Member]
Subsequent Events [Abstract]
Face value		$ 15,000
Interest rate		3.23%
Maturity date		Oct. 01, 2040
Proceeds from debt, net of issuance costs		$ 14,888
Subsequent Event [Member] \| 5.00% Monthly Senior Notes, Series 2010A, due 2040 [Member]
Subsequent Events [Abstract]
Face value		$ 15,000
Interest rate		5.00%
Maturity date		Oct. 01, 2040
Subsequent Event [Member] \| 3.00% PEDFA Exempt Facilities Revenue Refunding Bonds, Series A of 2019 [Member]
Subsequent Events [Abstract]
Face value	$ 10,500
Interest rate	3.00%
Maturity date	Oct. 01, 2036
Subsequent Event [Member] \| 3.10% PEDFA Exempt Facilities Revenue Refunding Bonds, Series B of 2019 [Member]
Subsequent Events [Abstract]
Face value	$ 14,870
Interest rate	3.10%
Maturity date	Nov. 01, 2038
Subsequent Event [Member] \| Series A and Series B Bonds [Member]
Subsequent Events [Abstract]
Proceeds from debt, net of issuance costs	$ 25,049
Subsequent Event [Member] \| 4.75% York County Industrial Development Authority Revenue Bonds, Series 2006, due 2036 [Member]
Subsequent Events [Abstract]
Face value	$ 10,500
Interest rate	4.75%
Maturity date	Oct. 01, 2036
Subsequent Event [Member] \| 4.50% Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2014, due 2038 [Member]
Subsequent Events [Abstract]
Face value	$ 14,870
Interest rate	4.50%
Maturity date	Nov. 01, 2038