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Fair Value of Financial Instruments - Equity Investments - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items] |  |  |  |  |
Equity investments, carrying value | $ 250,000,000 |  | $ 250,000,000 |  | $ 220,000,000
Equity investments, adjusted cost basis, amount | 18,000,000 |  | 18,000,000 |  | 17,000,000
Equity investments, impairments | $ 0 | $ 0 | $ 0 | $ 0 |
Waha JVs |  |  |  |  |
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items] |  |  |  |  |
Equity method investments, ownership percentage | 33.00% |  | 33.00% |  |
Equity investments, carrying value | $ 206,000,000 |  | $ 206,000,000 |  | 175,000,000
CCI |  |  |  |  |
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items] |  |  |  |  |
Equity investments, ownership percentage | 15.00% |  | 15.00% |  |
Equity investments, adjusted cost basis, amount | $ 15,000,000 |  | $ 15,000,000 |  |
FM Tech |  |  |  |  |
Fair Value, Financial Instruments Measured on a Non-Recurring Basis [Line Items] |  |  |  |  |
Equity method investments, ownership percentage | 50.00% |  | 50.00% |  |
Equity investments, carrying value | $ 17,000,000 |  | $ 17,000,000 |  | $ 16,000,000

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117539-209714 + Details
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