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Income Taxes - Reconciliation of U.S. Federal Statutory Tax Rate to Company's Effective Tax Rate (Details) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income tax provision |  |  |  |
Statutory U.S. federal tax rate |  | 21.00% | 21.00% | 35.00%
State income taxes, net of federal benefit |  | 3.50% | 3.70% | 2.70%
Foreign operations |  | (471.20%) | 1.30% | (5.40%)
Compensation plans |  | 240.60% | 1.60% | (0.70%)
Changes in tax laws |  | 0.00% | 0.00% | (25.20%)
Changes in valuation allowances |  | (107.20%) | 0.00% | 0.30%
Unrecognized tax benefits |  | 420.40% | 0.50% | 0.50%
Affiliate divestments |  | (120.40%) | 0.00% | 0.00%
Reduction in carrying value of Affiliates |  | 0.00% | 13.00% | 0.00%
Changes in U.S. tax provision to return |  | (195.70%) | (1.00%) | 0.00%
Other |  | 72.00% | 0.90% | (0.40%)
Effective tax rate (controlling interest) |  | (137.00%) | 41.00% | 6.80%
Non-Controlling Interests |  |  |  |
Income tax provision |  |  |  |
Effect of income from non-controlling interests |  | 137.90% | (15.60%) | (1.30%)
Controlling interests |  |  |  |
Income tax provision |  |  |  |
Effective tax rate (controlling interest) | [1] | (137.00%) | 41.00% | 6.80%
Effective tax rate |  | 0.90% | 25.40% | 5.50%
[1] | Taxes attributable to the controlling interest divided by Income before income taxes (controlling interest).

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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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