Balance Sheet Components Other Non-Current Liabilities and Deferred Credits (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Operating Lease, Liability, Noncurrent	$ 68,228	$ 0
Finance Lease, Liability, Noncurrent	53,150	0
Deferred investment tax credits	31,172	29,725
Asset Retirement Obligation	18,595	18,266
Derivative Liability, Noncurrent	27,198	10,300
Other	13,058	12,740
Other Liabilities, Noncurrent	$ 211,401	$ 71,031

The noncurrent portion of the reserve for accumulated deferred investment tax credits as of the balance sheet date. This is the remaining investment credit, which will reduce the cost of services collected from ratepayers by a ratable portion over the investment's regulatory life.

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer.

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