Debt and Credit Facilities - Margin for Borrowings under Revolving Credit Facility (Details) - Revolving Credit Facility	3 Months Ended
	Mar. 31, 2020 USD ($)
Minimum | III
Line of Credit Facility [Line Items]
Availability of borrowing	$ 30,000,000
Minimum | II
Line of Credit Facility [Line Items]
Availability of borrowing	15,000,000
Maximum | II
Line of Credit Facility [Line Items]
Availability of borrowing	30,000,000
Maximum | I
Line of Credit Facility [Line Items]
Availability of borrowing	$ 15,000,000
Tranche A | Base Rate | III
Line of Credit Facility [Line Items]
Basis spread (as a percent)	0.50%
Tranche A | Base Rate | II
Line of Credit Facility [Line Items]
Basis spread (as a percent)	0.75%
Tranche A | Base Rate | I
Line of Credit Facility [Line Items]
Basis spread (as a percent)	1.00%
Tranche A | LIBOR | III
Line of Credit Facility [Line Items]
Basis spread (as a percent)	1.50%
Tranche A | LIBOR | II
Line of Credit Facility [Line Items]
Basis spread (as a percent)	1.75%
Tranche A | LIBOR | I
Line of Credit Facility [Line Items]
Basis spread (as a percent)	2.00%
Tranche B | Base Rate | III
Line of Credit Facility [Line Items]
Basis spread (as a percent)	1.50%
Tranche B | Base Rate | II
Line of Credit Facility [Line Items]
Basis spread (as a percent)	1.75%
Tranche B | Base Rate | I
Line of Credit Facility [Line Items]
Basis spread (as a percent)	2.00%
Tranche B | LIBOR | III
Line of Credit Facility [Line Items]
Basis spread (as a percent)	2.50%
Tranche B | LIBOR | II
Line of Credit Facility [Line Items]
Basis spread (as a percent)	2.75%
Tranche B | LIBOR | I
Line of Credit Facility [Line Items]
Basis spread (as a percent)	3.00%