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Revenue from Contract with Customer - Contract Assets and Contract Liabilities (Details) - American States Utility Services [Member] - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
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Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |
Government Contract Receivable | $ 56,261 | $ 40,150
Contract with Customer, Asset, Net | 16,153 | 30,388
Contract with Customer, Liability | $ 7,043 | $ 3,911

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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130549-203045 + Details
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130549-203045 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 + Details
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- Definition The amount of receivables that are derived from government contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 912 -SubTopic 310 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68054760&loc=d3e55295-109406 + Details
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