Borrowings - Schedule of Line of Credit Facility Debt and Key Terms (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Amount Due	$ 120.3
5.75% 2024 Convertible Notes
Debt Instrument [Line Items]
Annual interest rate	5.75%
Maturity date	Nov. 30, 2024
Amount Due	$ 5.0	$ 5.0
June 2020 Note
Debt Instrument [Line Items]
Maturity date	Jun. 30, 2020
Amount Due	$ 2.6	2.6
December 2020 Note
Debt Instrument [Line Items]
Maturity date	Dec. 31, 2020
Amount Due	$ 2.6	2.6
The Mann Group L L C \| Convertible Promissory Note
Debt Instrument [Line Items]
Annual interest rate	7.00%
Maturity date	Nov. 30, 2024
Amount Due	$ 35.0	35.0
Accrued interest paid-in-kind	$ 1.6	1.0
The Mann Group L L C \| Non Convertible Promissory Note
Debt Instrument [Line Items]
Annual interest rate	7.00%
Maturity date	Nov. 30, 2024
Amount Due	$ 35.1	35.1
Accrued interest paid-in-kind	$ 1.6	1.0
MidCap Credit Facility
Debt Instrument [Line Items]
Maturity date	Aug. 31, 2024
Amount Due	$ 40.0	$ 40.0
MidCap Credit Facility \| LIBOR
Debt Instrument [Line Items]
Annual interest rate	6.75%
Interest rate floor	2.00%

Accrued paid in kind interest.

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- Definition

Debt instrument floor rate.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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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.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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