Commitments, Guarantees and Contingencies - Leasing Agreements (Details) $ in Millions |
Jun. 30, 2018
USD ($)
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| Leasing Agreements [Line Items] | |
| Minimum Lease Payments Due for Remainder of 2018 | $ 7.1 |
| Minimum Lease Payments Due in 2019 | 12.8 |
| Minimum Lease Payments Due in 2020 | 9.5 |
| Minimum Lease Payments Due in 2021 | 7.3 |
| Minimum Lease Payments Due in 2022 | 6.1 |
| Minimum Lease Payments Thereafter | 30.0 |
| BNI Energy Dragline [Member] | |
| Leasing Agreements [Line Items] | |
| Minimum Lease Payments Due Annually | 2.8 |
| Termination Fee | 3.0 |
| Minimum Lease Payments Due in 2019 | 2.8 |
| Minimum Lease Payments Due in 2020 | 2.8 |
| Minimum Lease Payments Due in 2021 | 2.8 |
| Minimum Lease Payments Due in 2022 | 2.8 |
| Minimum Lease Payments Thereafter | $ 14.0 |
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- Definition A lump sum payment in conjunction with a lease termination. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Details
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