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Intangible Assets (Details) (USD $) | 0 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Apr. 01, 2014 | Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Intangible Assets |  |  |  |  |
Amortization and impairment expenses of intangible assets |  | $ 28,700,000 | $ 32,700,000 | $ 84,200,000 | $ 98,100,000
Goodwill, Impairment Loss |  |  |  | 0 |
Tax deduction period for goodwill and client relationships amortization expense | 15 years |  |  |  |
Annual amortization expense attributable to current equity method Affiliates for next five years |  |  |  |  |
2014 |  | 120,000,000 |  | 120,000,000 |
2015 |  | 120,000,000 |  | 120,000,000 |
2016 |  | 120,000,000 |  | 120,000,000 |
Goodwill, Period Increase (Decrease) |  |  |  | 0 |
EIG Global Energy Partners, LLC |  |  |  |  |
Intangible Assets |  |  |  |  |
Acquired client relationships | 115,000,000 |  |  |  |
Acquired Client Relationships |  |  |  |  |
Intangible Assets |  |  |  |  |
Weighted average life |  |  |  | 10 years |
Amortization and impairment expenses of intangible assets |  | 28,700,000 | 32,700,000 | 84,200,000 | 98,100,000
Annual amortization expense attributable to current equity method Affiliates for next five years |  |  |  |  |
2017 |  | 120,000,000 |  | 120,000,000 |
2018 |  | 120,000,000 |  | 120,000,000 |
Acquired Client Relationships | EIG Global Energy Partners, LLC |  |  |  |  |
Intangible Assets |  |  |  |  |
Weighted average life |  |  |  | 12 years |
Amortization and impairment expenses of intangible assets |  | 7,300,000 | 10,400,000 | 20,000,000 | 31,100,000
Annual amortization expense attributable to current equity method Affiliates for next five years |  |  |  |  |
2014 |  | 26,400,000 |  | 26,400,000 |
2015 |  | 20,200,000 |  | 20,200,000 |
2016 |  | 17,600,000 |  | 17,600,000 |
2017 |  | 17,700,000 |  | 17,700,000 |
2018 |  | $ 17,700,000 |  | $ 17,700,000 |

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition The amount of identifiable intangible assets recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=25498275&loc=d3e2207-128464 + Details
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- Definition Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13854-109267 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267 + Details
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