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v3.19.3.a.u2

Segment Information - Schedule of Segment Reporting Information by Segment (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues before reimbursements |  |  |  |  |  |  |  |  | $ 7,056.4 | $ 6,792.4 | $ 6,113.0 |
Total revenues |  |  |  |  |  |  |  |  | 7,195.0 | 6,934.0 | 6,249.0 |
Compensation |  |  |  |  |  |  |  |  | 3,339.5 | 3,026.3 | 2,747.4 |
Operating |  |  |  |  |  |  |  |  | 1,068.5 | 903.7 | 829.1 |
Reimbursements |  |  |  |  |  |  |  |  | 138.6 | 141.6 | 136.0 |
Cost of revenues from clean coal activities |  |  |  |  |  |  |  |  | 1,352.8 | 1,816.0 | 1,635.9 |
Interest |  |  |  |  |  |  |  |  | 179.8 | 138.4 | 124.1 |
Depreciation |  |  |  |  |  |  |  |  | 140.4 | 127.8 | 121.1 |
Amortization |  |  |  |  |  |  |  |  | 334.0 | 291.2 | 264.7 |
Change in estimated acquisition earnout payables |  |  |  |  |  |  |  |  | 15.3 | 9.6 | 30.9 |
Total expenses |  |  |  |  |  |  |  |  | 6,568.9 | 6,454.6 | 5,889.2 |
Earnings (loss) before income taxes |  |  |  |  |  |  |  |  | 626.1 | 479.4 | 359.8 |
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  | (89.7) | (196.5) | (157.1) |
Net earnings (loss) |  |  |  |  |  |  |  |  | 715.8 | 675.9 | 516.9 |
Net earnings attributable to noncontrolling interests |  |  |  |  |  |  |  |  | 47.0 | 42.4 | 35.6 |
Net earnings (loss) attributable to controlling interests | $ 98.5 | $ 126.1 | $ 110.1 | $ 334.1 | $ 117.3 | $ 127.6 | $ 114.9 | $ 273.7 | 668.8 | 633.5 | 481.3 | [1]
Net foreign exchange gain |  |  |  |  |  |  |  |  | (6.7) | 2.9 | (3.9) |
Total revenues |  |  |  |  |  |  |  |  | 7,195.0 | 6,934.0 | 6,249.0 |
Total identifiable assets | 19,634.8 |  |  |  | 16,334.0 |  |  |  | 19,634.8 | 16,334.0 | 14,909.7 |
Goodwill - net | 5,618.5 |  |  |  | 4,625.6 |  |  |  | 5,618.5 | 4,625.6 | 4,164.8 |
Amortizable intangible assets - net | 2,318.7 |  |  |  | 1,773.0 |  |  |  | 2,318.7 | 1,773.0 | 1,644.6 |
Unites States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 5,379.1 | 5,377.8 | 4,839.3 |
Total revenues |  |  |  |  |  |  |  |  | 5,379.1 | 5,377.8 | 4,839.3 |
Total identifiable assets | 10,782.7 |  |  |  | 9,237.6 |  |  |  | 10,782.7 | 9,237.6 | 8,230.2 |
Goodwill - net | 3,196.9 |  |  |  | 2,744.9 |  |  |  | 3,196.9 | 2,744.9 |  |
United Kingdom [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 963.4 | 773.9 | 709.9 |
Total revenues |  |  |  |  |  |  |  |  | 963.4 | 773.9 | 709.9 |
Total identifiable assets | 5,091.1 |  |  |  | 3,862.3 |  |  |  | 5,091.1 | 3,862.3 | 3,587.5 |
Goodwill - net | 1,190.7 |  |  |  | 762.9 |  |  |  | 1,190.7 | 762.9 |  |
Australia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 298.6 | 290.6 | 269.3 |
Total revenues |  |  |  |  |  |  |  |  | 298.6 | 290.6 | 269.3 |
Total identifiable assets | 1,307.9 |  |  |  | 1,143.3 |  |  |  | 1,307.9 | 1,143.3 | 1,151.8 |
Goodwill - net | 427.0 |  |  |  | 406.6 |  |  |  | 427.0 | 406.6 |  |
Canada [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 226.0 | 185.4 | 153.6 |
Total revenues |  |  |  |  |  |  |  |  | 226.0 | 185.4 | 153.6 |
Total identifiable assets | 916.7 |  |  |  | 787.5 |  |  |  | 916.7 | 787.5 | 750.1 |
Goodwill - net | 454.4 |  |  |  | 378.6 |  |  |  | 454.4 | 378.6 |  |
New Zealand [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 160.8 | 157.5 | 149.7 |
Total revenues |  |  |  |  |  |  |  |  | 160.8 | 157.5 | 149.7 |
Total identifiable assets | 718.7 |  |  |  | 709.8 |  |  |  | 718.7 | 709.8 | 728.6 |
Goodwill - net | 218.1 |  |  |  | 219.8 |  |  |  | 218.1 | 219.8 |  |
Other Foreign [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 167.1 | 148.8 | 127.2 |
Total revenues |  |  |  |  |  |  |  |  | 167.1 | 148.8 | 127.2 |
Total identifiable assets | 817.7 |  |  |  | 593.5 |  |  |  | 817.7 | 593.5 | 461.5 |
Goodwill - net | 131.4 |  |  |  | 112.8 |  |  |  | 131.4 | 112.8 |  |
Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 4,901.5 |  |  |
Total revenues |  |  |  |  |  |  |  |  | 4,901.5 |  |  |
Goodwill - net | 5,548.9 |  |  |  | 4,573.6 |  |  |  | 5,548.9 | 4,573.6 | 4,119.2 |
Brokerage [Member] | Unites States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 3,163.8 |  |  |  | 2,715.3 |  |  |  | 3,163.8 | 2,715.3 |  |
Brokerage [Member] | United Kingdom [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 1,177.8 |  |  |  | 753.7 |  |  |  | 1,177.8 | 753.7 |  |
Brokerage [Member] | Australia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 416.5 |  |  |  | 406.3 |  |  |  | 416.5 | 406.3 |  |
Brokerage [Member] | Canada [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 454.4 |  |  |  | 378.6 |  |  |  | 454.4 | 378.6 |  |
Brokerage [Member] | New Zealand [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 208.0 |  |  |  | 209.6 |  |  |  | 208.0 | 209.6 |  |
Brokerage [Member] | Other Foreign [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 128.4 |  |  |  | 110.1 |  |  |  | 128.4 | 110.1 |  |
Risk Management [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 977.1 |  |  |
Total revenues |  |  |  |  |  |  |  |  | 977.1 |  |  |
Goodwill - net | 66.6 |  |  |  | 49.3 |  |  |  | 66.6 | 49.3 | 42.6 |
Risk Management [Member] | Unites States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 33.1 |  |  |  | 29.6 |  |  |  | 33.1 | 29.6 |  |
Risk Management [Member] | United Kingdom [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 12.9 |  |  |  | 9.2 |  |  |  | 12.9 | 9.2 |  |
Risk Management [Member] | Australia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 10.5 |  |  |  | 0.3 |  |  |  | 10.5 | 0.3 |  |
Risk Management [Member] | New Zealand [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 10.1 |  |  |  | 10.2 |  |  |  | 10.1 | 10.2 |  |
Corporate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,316.4 |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,316.4 |  |  |
Goodwill - net | 3.0 |  |  |  | 2.7 |  |  |  | 3.0 | 2.7 | 3.0 |
Corporate [Member] | Other Foreign [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Goodwill - net | 3.0 |  |  |  | 2.7 |  |  |  | 3.0 | 2.7 |  |
Commissions [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 3,320.6 | 2,920.7 | 2,641.0 |
Total revenues |  |  |  |  |  |  |  |  | 3,320.6 | 2,920.7 | 2,641.0 |
Broker Fees [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,911.1 | 1,756.3 | 1,591.9 |
Total revenues |  |  |  |  |  |  |  |  | 1,911.1 | 1,756.3 | 1,591.9 |
Supplemental Revenue Member [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 210.5 | 189.9 | 158.0 |
Total revenues |  |  |  |  |  |  |  |  | 210.5 | 189.9 | 158.0 |
Contingent Revenue [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 135.6 | 98.0 | 99.5 |
Total revenues |  |  |  |  |  |  |  |  | 135.6 | 98.0 | 99.5 |
Investment income [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 86.9 | 70.1 | 58.7 |
Total revenues |  |  |  |  |  |  |  |  | 86.9 | 70.1 | 58.7 |
Gains on Books of Business Sales [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 75.3 | 10.2 | 3.4 |
Total revenues |  |  |  |  |  |  |  |  | 75.3 | 10.2 | 3.4 |
Clean Coal Activities [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,319.3 | 1,746.3 | 1,560.5 |
Total revenues |  |  |  |  |  |  |  |  | 1,319.3 | 1,746.3 | 1,560.5 |
Product and Service, Other [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | (2.9) | 0.9 |  |
Total revenues |  |  |  |  |  |  |  |  | (2.9) | 0.9 |  |
Reimbursements [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 138.6 | 141.6 | 136.0 |
Total revenues |  |  |  |  |  |  |  |  | 138.6 | 141.6 | 136.0 |
Operating Segments [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  |  |  | 6,249.0 |
Total revenues |  |  |  |  |  |  |  |  |  |  | 6,249.0 |
Operating Segments [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues before reimbursements |  |  |  |  |  |  |  |  | 4,901.5 | 4,246.9 | 3,815.1 |
Total revenues |  |  |  |  |  |  |  |  | 4,901.5 | 4,246.9 | 3,815.1 |
Compensation |  |  |  |  |  |  |  |  | 2,745.9 | 2,447.1 | 2,212.3 |
Operating |  |  |  |  |  |  |  |  | 796.5 | 673.5 | 614.0 |
Depreciation |  |  |  |  |  |  |  |  | 66.6 | 60.9 | 61.8 |
Amortization |  |  |  |  |  |  |  |  | 329.1 | 286.9 | 261.8 |
Change in estimated acquisition earnout payables |  |  |  |  |  |  |  |  | 16.9 | 14.3 | 29.3 |
Total expenses |  |  |  |  |  |  |  |  | 3,955.0 | 3,482.7 | 3,179.2 |
Earnings (loss) before income taxes |  |  |  |  |  |  |  |  | 946.5 | 764.2 | 635.9 |
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  | 229.2 | 191.0 | 221.2 |
Net earnings (loss) |  |  |  |  |  |  |  |  | 717.3 | 573.2 | 414.7 |
Net earnings attributable to noncontrolling interests |  |  |  |  |  |  |  |  | 17.2 | 10.7 | 7.6 |
Net earnings (loss) attributable to controlling interests |  |  |  |  |  |  |  |  | 700.1 | 562.5 | 407.1 |
Net foreign exchange gain |  |  |  |  |  |  |  |  | (1.0) |  | (2.0) |
Total revenues |  |  |  |  |  |  |  |  | 4,901.5 | 4,246.9 | 3,815.1 |
Total identifiable assets | 16,741.9 |  |  |  | 13,785.1 |  |  |  | 16,741.9 | 13,785.1 | 12,404.3 |
Goodwill - net | 5,548.9 |  |  |  | 4,573.7 |  |  |  | 5,548.9 | 4,573.7 | 4,119.2 |
Amortizable intangible assets - net | 2,289.9 |  |  |  | 1,753.7 |  |  |  | 2,289.9 | 1,753.7 | 1,630.6 |
Operating Segments [Member] | Brokerage [Member] | Unites States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 3,234.3 | 2,840.9 | 2,533.7 |
Total revenues |  |  |  |  |  |  |  |  | 3,234.3 | 2,840.9 | 2,533.7 |
Total identifiable assets | 8,132.3 |  |  |  | 6,865.4 |  |  |  | 8,132.3 | 6,865.4 | 5,890.5 |
Operating Segments [Member] | Brokerage [Member] | United Kingdom [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 921.8 | 738.5 | 679.3 |
Total revenues |  |  |  |  |  |  |  |  | 921.8 | 738.5 | 679.3 |
Total identifiable assets | 4,964.5 |  |  |  | 3,758.5 |  |  |  | 4,964.5 | 3,758.5 | 3,496.2 |
Operating Segments [Member] | Brokerage [Member] | Australia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 211.3 | 195.9 | 191.1 |
Total revenues |  |  |  |  |  |  |  |  | 211.3 | 195.9 | 191.1 |
Total identifiable assets | 1,217.9 |  |  |  | 1,096.1 |  |  |  | 1,217.9 | 1,096.1 | 1,102.9 |
Operating Segments [Member] | Brokerage [Member] | Canada [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 221.4 | 181.1 | 149.4 |
Total revenues |  |  |  |  |  |  |  |  | 221.4 | 181.1 | 149.4 |
Total identifiable assets | 913.6 |  |  |  | 783.1 |  |  |  | 913.6 | 783.1 | 743.3 |
Operating Segments [Member] | Brokerage [Member] | New Zealand [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 145.6 | 141.7 | 134.4 |
Total revenues |  |  |  |  |  |  |  |  | 145.6 | 141.7 | 134.4 |
Total identifiable assets | 695.9 |  |  |  | 688.5 |  |  |  | 695.9 | 688.5 | 709.9 |
Operating Segments [Member] | Brokerage [Member] | Other Foreign [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 167.1 | 148.8 | 127.2 |
Total revenues |  |  |  |  |  |  |  |  | 167.1 | 148.8 | 127.2 |
Total identifiable assets | 817.7 |  |  |  | 593.5 |  |  |  | 817.7 | 593.5 | 461.5 |
Operating Segments [Member] | Risk Management [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues before reimbursements |  |  |  |  |  |  |  |  | 838.5 | 798.3 | 737.4 |
Total revenues |  |  |  |  |  |  |  |  | 977.1 | 939.9 | 873.4 |
Compensation |  |  |  |  |  |  |  |  | 515.7 | 489.7 | 446.9 |
Operating |  |  |  |  |  |  |  |  | 184.9 | 174.6 | 164.8 |
Reimbursements |  |  |  |  |  |  |  |  | 138.6 | 141.6 | 136.0 |
Depreciation |  |  |  |  |  |  |  |  | 46.2 | 38.7 | 31.1 |
Amortization |  |  |  |  |  |  |  |  | 4.9 | 4.3 | 2.9 |
Change in estimated acquisition earnout payables |  |  |  |  |  |  |  |  | (1.6) | (4.7) | 1.6 |
Total expenses |  |  |  |  |  |  |  |  | 888.7 | 844.2 | 783.3 |
Earnings (loss) before income taxes |  |  |  |  |  |  |  |  | 88.4 | 95.7 | 90.1 |
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  | 22.2 | 25.3 | 34.4 |
Net earnings (loss) |  |  |  |  |  |  |  |  | 66.2 | 70.4 | 55.7 |
Net earnings (loss) attributable to controlling interests |  |  |  |  |  |  |  |  | 66.2 | 70.4 | 55.7 |
Net foreign exchange gain |  |  |  |  |  |  |  |  | (0.1) |  | (0.1) |
Total revenues |  |  |  |  |  |  |  |  | 977.1 | 939.9 | 873.4 |
Total identifiable assets | 898.1 |  |  |  | 748.1 |  |  |  | 898.1 | 748.1 | 738.6 |
Goodwill - net | 66.6 |  |  |  | 49.2 |  |  |  | 66.6 | 49.2 | 42.6 |
Amortizable intangible assets - net | 28.8 |  |  |  | 19.3 |  |  |  | 28.8 | 19.3 | 14.0 |
Operating Segments [Member] | Risk Management [Member] | Unites States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 828.4 | 789.7 | 745.1 |
Total revenues |  |  |  |  |  |  |  |  | 828.4 | 789.7 | 745.1 |
Total identifiable assets | 655.6 |  |  |  | 571.4 |  |  |  | 655.6 | 571.4 | 572.9 |
Operating Segments [Member] | Risk Management [Member] | United Kingdom [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 41.6 | 35.4 | 30.6 |
Total revenues |  |  |  |  |  |  |  |  | 41.6 | 35.4 | 30.6 |
Total identifiable assets | 126.6 |  |  |  | 103.8 |  |  |  | 126.6 | 103.8 | 91.3 |
Operating Segments [Member] | Risk Management [Member] | Australia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 87.3 | 94.7 | 78.2 |
Total revenues |  |  |  |  |  |  |  |  | 87.3 | 94.7 | 78.2 |
Total identifiable assets | 90.0 |  |  |  | 47.2 |  |  |  | 90.0 | 47.2 | 48.9 |
Operating Segments [Member] | Risk Management [Member] | Canada [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 4.6 | 4.3 | 4.2 |
Total revenues |  |  |  |  |  |  |  |  | 4.6 | 4.3 | 4.2 |
Total identifiable assets | 3.1 |  |  |  | 4.4 |  |  |  | 3.1 | 4.4 | 6.8 |
Operating Segments [Member] | Risk Management [Member] | New Zealand [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 15.2 | 15.8 | 15.3 |
Total revenues |  |  |  |  |  |  |  |  | 15.2 | 15.8 | 15.3 |
Total identifiable assets | 22.8 |  |  |  | 21.3 |  |  |  | 22.8 | 21.3 | 18.7 |
Operating Segments [Member] | Corporate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues before reimbursements |  |  |  |  |  |  |  |  | 1,316.4 | 1,747.2 | 1,560.5 |
Total revenues |  |  |  |  |  |  |  |  | 1,316.4 | 1,747.2 | 1,560.5 |
Compensation |  |  |  |  |  |  |  |  | 77.9 | 89.5 | 88.2 |
Operating |  |  |  |  |  |  |  |  | 87.1 | 55.6 | 50.3 |
Cost of revenues from clean coal activities |  |  |  |  |  |  |  |  | 1,352.8 | 1,816.0 | 1,635.9 |
Interest |  |  |  |  |  |  |  |  | 179.8 | 138.4 | 124.1 |
Depreciation |  |  |  |  |  |  |  |  | 27.6 | 28.2 | 28.2 |
Total expenses |  |  |  |  |  |  |  |  | 1,725.2 | 2,127.7 | 1,926.7 |
Earnings (loss) before income taxes |  |  |  |  |  |  |  |  | (408.8) | (380.5) | (366.2) |
Provision (benefit) for income taxes |  |  |  |  |  |  |  |  | (341.1) | (412.8) | (412.7) |
Net earnings (loss) |  |  |  |  |  |  |  |  | (67.7) | 32.3 | 46.5 |
Net earnings attributable to noncontrolling interests |  |  |  |  |  |  |  |  | 29.8 | 31.7 | 28.0 |
Net earnings (loss) attributable to controlling interests |  |  |  |  |  |  |  |  | (97.5) | 0.6 | 18.5 |
Net foreign exchange gain |  |  |  |  |  |  |  |  | (5.6) | 2.9 | (1.8) |
Total revenues |  |  |  |  |  |  |  |  | 1,316.4 | 1,747.2 | 1,560.5 |
Total identifiable assets | 1,994.8 |  |  |  | 1,800.8 |  |  |  | 1,994.8 | 1,800.8 | 1,766.8 |
Goodwill - net | 3.0 |  |  |  | 2.7 |  |  |  | 3.0 | 2.7 | 3.0 |
Operating Segments [Member] | Corporate [Member] | Unites States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,316.4 | 1,747.2 | 1,560.5 |
Total revenues |  |  |  |  |  |  |  |  | 1,316.4 | 1,747.2 | 1,560.5 |
Total identifiable assets | $ 1,994.8 |  |  |  | $ 1,800.8 |  |  |  | 1,994.8 | 1,800.8 | 1,766.8 |
Operating Segments [Member] | Commissions [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 3,320.6 | 2,920.7 | 2,641.0 |
Total revenues |  |  |  |  |  |  |  |  | 3,320.6 | 2,920.7 | 2,641.0 |
Operating Segments [Member] | Broker Fees [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,074.2 | 958.5 | 855.1 |
Total revenues |  |  |  |  |  |  |  |  | 1,074.2 | 958.5 | 855.1 |
Operating Segments [Member] | Broker Fees [Member] | Risk Management [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 836.9 | 797.8 | 736.8 |
Total revenues |  |  |  |  |  |  |  |  | 836.9 | 797.8 | 736.8 |
Operating Segments [Member] | Supplemental Revenue Member [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 210.5 | 189.9 | 158.0 |
Total revenues |  |  |  |  |  |  |  |  | 210.5 | 189.9 | 158.0 |
Operating Segments [Member] | Contingent Revenue [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 135.6 | 98.0 | 99.5 |
Total revenues |  |  |  |  |  |  |  |  | 135.6 | 98.0 | 99.5 |
Operating Segments [Member] | Investment income [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 85.3 | 69.6 | 58.1 |
Total revenues |  |  |  |  |  |  |  |  | 85.3 | 69.6 | 58.1 |
Operating Segments [Member] | Investment income [Member] | Risk Management [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1.6 | 0.5 | 0.6 |
Total revenues |  |  |  |  |  |  |  |  | 1.6 | 0.5 | 0.6 |
Operating Segments [Member] | Gains on Books of Business Sales [Member] | Brokerage [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 75.3 | 10.2 | 3.4 |
Total revenues |  |  |  |  |  |  |  |  | 75.3 | 10.2 | 3.4 |
Operating Segments [Member] | Clean Coal Activities [Member] | Corporate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 1,319.3 | 1,746.3 | 1,560.5 |
Total revenues |  |  |  |  |  |  |  |  | 1,319.3 | 1,746.3 | 1,560.5 |
Operating Segments [Member] | Product and Service, Other [Member] | Corporate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | (2.9) | 0.9 |  |
Total revenues |  |  |  |  |  |  |  |  | (2.9) | 0.9 |  |
Operating Segments [Member] | Reimbursements [Member] | Risk Management [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 138.6 | 141.6 | 136.0 |
Total revenues |  |  |  |  |  |  |  |  | $ 138.6 | $ 141.6 | $ 136.0 |
[1] | See Note 3 - Revenues from Contracts with Customers for additional information about the restatements related to Topic 606.

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