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Commitments, Contingencies and Off-Balance Sheet Arrangements - Off-Balance Sheet Commitments (Detail) $ in Millions | 3 Months Ended
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Mar. 31, 2017 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Amount of Commitment Expiration by Period - 2017 | $ 0.1
Amount of Commitment Expiration by Period - 2018 | 0.2
Amount of Commitment Expiration by Period - 2019 | 0.2
Amount of Commitment Expiration by Period - 2020 | 0.2
Amount of Commitment Expiration by Period - 2021 | 0.2
Amount of Commitment Expiration by Period - Thereafter | 22.9
Total Amounts Committed | 23.8
Letters of Credit [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Amount of Commitment Expiration by Period - Thereafter | 21.1
Total Amounts Committed | 21.1
Financial Guarantees [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Amount of Commitment Expiration by Period - 2017 | 0.1
Amount of Commitment Expiration by Period - 2018 | 0.2
Amount of Commitment Expiration by Period - 2019 | 0.2
Amount of Commitment Expiration by Period - 2020 | 0.2
Amount of Commitment Expiration by Period - 2021 | 0.2
Amount of Commitment Expiration by Period - Thereafter | 1.4
Total Amounts Committed | 2.3
Funding Commitments [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Amount of Commitment Expiration by Period - Thereafter | 0.4
Total Amounts Committed | $ 0.4

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- Details
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