Balance Sheet Components - Other Property and Investments-Net and Other Non-current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Operating lease ROU assets	$ 71,891	$ 69,746
Finance lease ROU assets	47,338	50,980
Non-utility property	19,508	27,159
Equity investments	59,318	51,258
Investment in affiliated trust	11,547	11,547
Notes receivable	14,454	14,060
Deferred compensation assets	9,174	8,948
Assets held for sale	3,462
Other	26,947	23,394
Total	$ 263,639	$ 257,092

Assets held for sale.

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- Definition

Non regulated property.

+ References

No definition available.

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- References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

+ 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
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

Amount, after accumulated amortization, of right-of-use asset from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Amount of investments, and noncurrent assets classified as other.

+ References

No definition available.

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- Definition

Amount of investment in equity method investee and investment in and advance to affiliate.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount, after allowance for credit loss, of financing receivable, classified as noncurrent.

+ 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(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

+ Details

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- Definition

Amount of noncurrent assets classified as other.

+ References

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