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v3.19.3.a.u2

Derivatives - Interest Rate Swap (Details) - USD ($) | 3 Months Ended | 8 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2019 | Jun. 15, 2018 | May 11, 2018
Derivative [Line Items] |  |  |  |  |
Debt | $ 283,500,000 | $ 192,700,000 | $ 283,500,000 |  |
NSM Holding Co LLC |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Debt | 219,200,000 | 178,500,000 | 219,200,000 |  |
NSM Bank Facility | NSM Holding Co LLC |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total commitment under revolving credit facility |  |  |  |  | $ 234,000,000.0
NSM Bank Facility | NSM Holding Co LLC | Term Loan |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total commitment under revolving credit facility |  |  |  |  | $ 224,000,000.0
Debt | $ 217,400,000 | $ 176,600,000 | $ 217,400,000 |  |
NSM Bank Facility | NSM Holding Co LLC | Term Loan | London Interbank Offered Rate (LIBOR) | Minimum |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Basis spread on variable rate | 4.25% | 4.25% |  |  |
NSM Bank Facility | NSM Holding Co LLC | Term Loan | London Interbank Offered Rate (LIBOR) | Maximum |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Basis spread on variable rate | 4.75% | 4.75% |  |  |
NSM Bank Facility | NSM Holding Co LLC | Term Loan | Prime Rate | Minimum |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Basis spread on variable rate | 3.25% | 3.25% |  |  |
NSM Bank Facility | NSM Holding Co LLC | Term Loan | Prime Rate | Maximum |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Basis spread on variable rate | 3.75% | 3.75% |  |  |
Interest Rate Swap | NSM Holding Co LLC |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Fixed interest rate | 2.97% |  | 2.97% |  |
Variable interest rate | 1.71% |  | 1.71% |  |
Net interest expense |  | $ 700,000 | $ 1,100,000 |  |
Derivative, fair value, net | $ 6,600,000 | 2,700,000 | 6,600,000 |  |
Change in the fair value of the swap |  | $ (2,700,000) | $ (3,900,000) |  |
Interest Rate Swap | NSM Bank Facility | NSM Holding Co LLC | Term Loan |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total commitment under revolving credit facility |  |  |  | $ 151,000,000.0 |
Fixed interest rate | 2.97% |  | 2.97% |  |
Debt | $ 148,700,000 |  | $ 148,700,000 |  |
Debt, weighted average interest rate | 7.06% |  | 7.06% |  |
Designated as Hedging Instrument | Interest Rate Swap | NSM Bank Facility | NSM Holding Co LLC | Term Loan |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Debt | $ 148,700,000 |  | $ 148,700,000 |  |
Debt, weighted average interest rate | 7.47% |  | 7.47% |  |

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