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Fair Value Measurements - Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring and Non-Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
Investment debt securities available-for-sale | 6,783.4 |  | 6,783.4 |  | $ 4,820.5
Derivative assets | 42.7 |  | 42.7 |  | 28.1
Derivative liabilities | 169.9 |  | 169.9 |  | 18.2
Write downs | (0.2) | $ 0.0 | (0.2) | $ 0.0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Loans held for sale | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan assets | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan liabilities | 0.0 |  | 0.0 |  | 0.0
Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Loans held for sale | 93.6 |  | 93.6 |  | 30.1
Deferred compensation plan assets | 19.0 |  | 19.0 |  | 21.4
Deferred compensation plan liabilities | 19.0 |  | 19.0 |  | 21.4
Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Loans held for sale | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan assets | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan liabilities | 0.0 |  | 0.0 |  | 0.0
U.S. Treasury notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 336.8 |  | 336.8 |  | 684.7
U.S. Treasury notes | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 336.8 |  | 336.8 |  | 684.7
U.S. Treasury notes | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
U.S. Treasury notes | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
State, county, and municipal securities |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 260.5 |  | 260.5 |  | 427.5
State, county, and municipal securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
State, county, and municipal securities | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 260.5 |  | 260.5 |  | 427.5
State, county, and municipal securities | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Obligations of U.S. government agencies |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 199.0 |  | 199.0 |  | 346.9
Obligations of U.S. government agencies | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Obligations of U.S. government agencies | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 199.0 |  | 199.0 |  | 346.9
Obligations of U.S. government agencies | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
U.S. agency residential & commercial mortgage-backed securities & collateralized mortgage obligations |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 4,409.7 |  | 4,409.7 |  | 2,018.1
U.S. agency residential & commercial mortgage-backed securities & collateralized mortgage obligations | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
U.S. agency residential & commercial mortgage-backed securities & collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 4,409.7 |  | 4,409.7 |  | 2,018.1
U.S. agency residential & commercial mortgage-backed securities & collateralized mortgage obligations | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Private mortgage-backed securities |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 233.2 |  | 233.2 |  | 173.4
Private mortgage-backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Private mortgage-backed securities | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 233.2 |  | 233.2 |  | 173.4
Private mortgage-backed securities | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Corporate securities |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 239.1 |  | 239.1 |  | 270.5
Corporate securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Corporate securities | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 239.1 |  | 239.1 |  | 270.5
Corporate securities | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Collateral dependent loans | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Collateral dependent loans | 0.0 |  | 0.0 |  | 0.0
Collateral dependent loans | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Collateral dependent loans | 0.0 |  | 0.0 |  | 0.0
Collateral dependent loans | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Collateral dependent loans |  |  |  |  | 11.7
Collateralized Loan Obligations |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 1,105.1 |  | 1,105.1 |  | 899.4
Collateralized Loan Obligations | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Collateralized Loan Obligations | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 1,105.1 |  | 1,105.1 |  | 899.4
Collateralized Loan Obligations | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Estimated Fair Value |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 6,783.4 |  | 6,783.4 |  | 4,820.5
Derivative assets | 42.7 |  | 42.7 |  | 28.1
Derivative liabilities | 169.9 |  | 169.9 |  | 18.2
Deferred compensation plan assets | 19.0 |  | 19.0 |  | 21.4
Deferred compensation plan liabilities | 19.0 |  | 19.0 |  | 21.4
Estimated Fair Value | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Loans held for sale | 93.6 |  | 93.6 |  | 30.1
Deferred compensation plan assets | 19.0 |  | 19.0 |  | 21.4
Deferred compensation plan liabilities | 19.0 |  | 19.0 |  | 21.4
Estimated Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 336.8 |  | 336.8 |  | 684.7
Derivative assets | 0.0 |  | 0.0 |  | 0.0
Derivative liabilities | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan assets | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan liabilities | 0.0 |  | 0.0 |  | 0.0
Estimated Fair Value | Significant Other Observable Inputs (Level 2) |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 6,446.6 |  | 6,446.6 |  | 4,135.8
Derivative assets | 42.7 |  | 42.7 |  | 28.1
Derivative liabilities | 169.9 |  | 169.9 |  | 18.2
Deferred compensation plan assets | 19.0 |  | 19.0 |  | 21.4
Deferred compensation plan liabilities | 19.0 |  | 19.0 |  | 21.4
Estimated Fair Value | Significant Unobservable Inputs (Level 3) |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 0.0 |  | 0.0 |  | 0.0
Derivative assets | 0.0 |  | 0.0 |  | 0.0
Derivative liabilities | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan assets | 0.0 |  | 0.0 |  | 0.0
Deferred compensation plan liabilities | 0.0 |  | 0.0 |  | 0.0
Estimated Fair Value | U.S. Treasury notes | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 336.8 |  | 336.8 |  | 684.7
Estimated Fair Value | State, county, and municipal securities | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 260.5 |  | 260.5 |  | 427.5
Estimated Fair Value | Obligations of U.S. government agencies | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 199.0 |  | 199.0 |  | 346.9
Estimated Fair Value | U.S. agency residential & commercial mortgage-backed securities & collateralized mortgage obligations | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 4,409.7 |  | 4,409.7 |  | 2,018.1
Estimated Fair Value | Private mortgage-backed securities | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 233.2 |  | 233.2 |  | 173.4
Estimated Fair Value | Corporate securities | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 239.1 |  | 239.1 |  | 270.5
Estimated Fair Value | Collateral dependent loans | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Collateral dependent loans | 57.6 |  | 57.6 |  | 11.7
Estimated Fair Value | Collateralized Loan Obligations | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 1,105.1 |  | 1,105.1 |  | 899.4
Carrying Amount |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Investment debt securities available-for-sale | 6,783.4 |  | 6,783.4 |  | 4,820.5
Derivative assets | 42.7 |  | 42.7 |  | 28.1
Derivative liabilities | 169.9 |  | 169.9 |  | 18.2
Deferred compensation plan assets | 19.0 |  | 19.0 |  | 21.4
Deferred compensation plan liabilities | 19.0 |  | 19.0 |  | 21.4
Carrying Amount | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Collateral dependent loans | 57.6 |  | 57.6 |  | 11.7
Long-lived assets to be disposed of by sale | 6.7 |  | 6.7 |  | 1.3
Interest Rate Swap |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 42.1 |  | 42.1 |  | 26.3
Derivative liabilities | 169.3 |  | 169.3 |  | 18.2
Interest Rate Swap | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 0.0 |  | 0.0 |  | 0.0
Derivative liabilities | 0.0 |  | 0.0 |  | 0.0
Interest Rate Swap | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 42.1 |  | 42.1 |  | 26.3
Derivative liabilities | 163.7 |  | 163.7 |  | 18.2
Interest Rate Swap | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 0.0 |  | 0.0 |  | 0.0
Derivative liabilities | 0.0 |  | 0.0 |  | 0.0
Interest Rate Swap | Estimated Fair Value | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 42.1 |  | 42.1 |  | 26.3
Derivative liabilities | 163.7 |  | 163.7 |  | 18.2
Interest Rate Lock Commitments | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets |  |  |  |  | 0.0
Derivative liabilities | 0.0 |  | 0.0 |  |
Interest Rate Lock Commitments | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets |  |  |  |  | 1.8
Derivative liabilities | 0.5 |  | 0.5 |  |
Interest Rate Lock Commitments | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets |  |  |  |  | 0.0
Derivative liabilities | 0.0 |  | 0.0 |  |
Interest Rate Lock Commitments | Estimated Fair Value | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets |  |  |  |  | 1.8
Derivative liabilities | 0.5 |  | 0.5 |  |
Forward Contracts | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 0.0 |  | 0.0 |  |
Forward Contracts | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 0.6 |  | 0.6 |  |
Forward Contracts | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 0.0 |  | 0.0 |  |
Forward Contracts | Estimated Fair Value | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative assets | 0.6 |  | 0.6 |  |
Risk Participation Agreements |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.1 |  | 0.1 |  |
Risk Participation Agreements | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.0 |  | 0.0 |  |
Risk Participation Agreements | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.1 |  | 0.1 |  |
Risk Participation Agreements | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.0 |  | 0.0 |  |
Risk Participation Agreements | Estimated Fair Value | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.1 |  | 0.1 |  |
Interest Rate Collars | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.0 |  | 0.0 |  |
Interest Rate Collars | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 5.6 |  | 5.6 |  |
Interest Rate Collars | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 0.0 |  | 0.0 |  |
Interest Rate Collars | Estimated Fair Value | Fair Value Measured on a Recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Derivative liabilities | 5.6 |  | 5.6 |  |
Long-lived assets to be disposed of by sale | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Long-lived assets to be disposed of by sale | 0.0 |  | 0.0 |  | 0.0
Long-lived assets to be disposed of by sale | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Long-lived assets to be disposed of by sale | 0.0 |  | 0.0 |  | 0.0
Long-lived assets to be disposed of by sale | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Long-lived assets to be disposed of by sale | 6.7 |  | 6.7 |  | 1.3
Long-lived assets to be disposed of by sale | Estimated Fair Value | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Long-lived assets to be disposed of by sale | $ 6.7 |  | $ 6.7 |  | $ 1.3

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