Senior Debt Senior Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Aug. 05, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Senior debt	$ 239,500		$ 0
Original issue discount		$ 2,000
Debt issuance costs		$ 6,300
Unamortized debt issuance expense	(8,587)		(2,600)
Letters of credit, amount outstanding	92,000
Senior debt, net	230,913		0
2020	2,000
2021	2,000
2022	2,000
2023	2,000
2024	42,000
Thereafter	189,500
Debt Issuance Costs [Member]
Debt Instrument [Line Items]
Unamortized debt issuance expense	(6,700)
Original Issue Discount [Member]
Debt Instrument [Line Items]
Unamortized debt issuance expense	(1,900)
Term loan [Member]
Debt Instrument [Line Items]
Senior debt	199,500		0
Maximum borrowing capacity	200,000		0
Amount available	$ 0		0
Maturity date	Aug. 05, 2026
Frequency of periodic payment	quarterly
Periodic Payment, Percent	1.00%
Required consolidated senior secured leverage ratio, minimum	2.00
2020	$ 2,000
2021	2,000
2022	2,000
2023	2,000
2024	2,000
Thereafter	189,500
Term loan [Member] | Maximum [Member]
Debt Instrument [Line Items]
Senior debt	$ 200,000
Term loan [Member] | Eurodollar [Member]
Debt Instrument [Line Items]
Basis margin on variable rate	4.50%
Actual margin on variable rate	6.25%
ABL credit facility [Member]
Debt Instrument [Line Items]
Senior debt	$ 40,000		0
Maximum borrowing capacity	300,000		200,000
ABL credit facility availability	$ 168,200		95,900
Maturity date	Aug. 05, 2024
Line of credit commitment fee percentage	0.375%
Line of credit commitment fee	$ 500
Line of credit additional borrowing capacity	$ 100,000
Required minimum proforma fixed charge coverage ratio	1.10
Required minimum consolidated fixed charge coverage ratio	1.10
2020	$ 0
2021	0
2022	0
2023	0
2024	40,000
Thereafter	$ 0
ABL credit facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Line of credit commitment fee percentage	0.25%
ABL credit facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Senior debt	$ 300,000
Letters of credit, amount outstanding	$ 150,000
Line of credit commitment fee percentage	0.375%
ABL credit facility [Member] | Eurodollar [Member]
Debt Instrument [Line Items]
Actual margin on variable rate	3.25%
ABL credit facility [Member] | Eurodollar [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis margin on variable rate	1.50%
ABL credit facility [Member] | Eurodollar [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis margin on variable rate	2.00%
Term Loan and Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000		200,000
Amount available	168,200		95,900
Line of Credit [Member]
Debt Instrument [Line Items]
Unsecured line of credit, maximum facility	0		12,500
Unsecured line of credit, amount outstanding	0		0
Amount available	0		12,500
Senior Debt [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	500,000		212,500
Amount outstanding	239,500		0
Amount available	$ 168,200		$ 108,400