Name:	exc_EquityMethodInvestmentDifferenceBetweenCarryingAmountAndConsideration
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting sold.

No definition available.

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Represents the number of shares issued to acquire equity method investment.

No definition available.

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Represents the value of shares issued to acquire equity method investment.

No definition available.

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Balance Type:	credit
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Long-Term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. This does not include advances to clients.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 850
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The total amount of dividends declared in the period for each class of stock and the contractual amount of dividends (or interest on participating income bonds) that must be paid for the period (for example, unpaid cumulative dividends). Dividends declared in the current period do not include dividends declared in respect of prior-period unpaid cumulative dividends. Preferred dividends that are cumulative only if earned are deducted only to the extent that they are earned.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 323
-SubTopic 10
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Balance Type:	debit
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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-Name Accounting Standards Codification
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-Paragraph 1
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-Topic 323
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-Publisher FASB
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(10))
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or the sale of investment in consolidated subsidiaries (generally greater than 50 percent).

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-Name Accounting Standards Codification
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The cash inflow from the sale of an investment interest in a joint venture that the reporting entity has not previously accounted for using consolidation or the equity method of accounting.

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Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50 percent or less owned persons accounted for by the equity method (equity method investees).

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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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
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-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
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-Topic 323
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-Topic 323
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Name:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Price of a single share of a number of saleable stocks of a company.

No definition available.

Name:	us-gaap_SharePrice
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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

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Period Type:

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Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=exc_HubeiDongjunAutomotiveElectronicsTechnologyCo.Ltd.Member
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