Debt - Credit Facility with a Lending Consortium Arranged by SunTrust (Details)	Oct. 01, 2019 USD ($)	May 08, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Long-term debt, gross			$ 349,684,000	$ 330,350,000
Truist | Revolving Credit Facility
Debt Instrument [Line Items]
Total net debt ratio, maximum	3.00
EBITDA Ratio, Maximum	1.00
Long-Term Debt, Threshold For EBITDA Ration Increase Election	$ 50,000,000
Total Net Debt Ratio, Maximum After Increase Election	3.50
EBITDA Ratio. Maximum After Increase Election	1.00
Total net debt ratio, minimum	1.50
EBITDA Ratio, Minimum	1.00
Long-term debt, gross			230,000,000	$ 210,000,000
Truist | Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.25%
Truist | Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.45%
Truist | Revolving Credit Facility | Third Amended Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 350,000,000
Long-term debt, gross			$ 230,000,000
Truist | Revolving Credit Facility | Third Amended Credit Facility | Subsequent Event
Debt Instrument [Line Items]
Long-term debt, gross		$ 110,000,000
Truist | Revolving Credit Facility | Base Rate | Minimum
Debt Instrument [Line Items]
Interest rate margin	0.50%
Truist | Revolving Credit Facility | Base Rate | Maximum
Debt Instrument [Line Items]
Interest rate margin	1.50%
Truist | Revolving Credit Facility | LIBOR | Minimum
Debt Instrument [Line Items]
Interest rate margin	1.50%
Truist | Revolving Credit Facility | LIBOR | Maximum
Debt Instrument [Line Items]
Interest rate margin	2.50%