Borrowing Arrangements - Additional Information (Details) - USD ($)		1 Months Ended	12 Months Ended
	Feb. 20, 2015	May 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2018
Debt Instrument [Line Items]
Notional amount			$ 222,300,000
Redemption value of convertible debentures outstanding			1,100,000	$ 1,100,000
Senior Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Amount of senior credit facility aggregated			$ 369,000,000.0
Weighted average interest rate on senior credit facility (in percentage)			3.60%	4.30%
Convertible debentures
Debt Instrument [Line Items]
Redemption price (in USD per share)			$ 19.18
Debt redemptions			$ 0	$ 0
Restated credit agreement
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 550,000,000
Percentage of scheduled quarterly amortization (in percentage)			1.25%
Restated credit agreement | Senior Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 174,800,000		325,000,000
Letters of credit outstanding			$ 50,200,000
Restated credit agreement | Letter of credit facility
Debt Instrument [Line Items]
Maximum borrowing capacity					100,000,000
Restated credit agreement | Term loan facility
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 225,000,000
Restated credit agreement | Maximum | Senior Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Total debt to EBITDA ratio that is required to be maintained (less than)	4.00
Restated credit agreement | Minimum | Senior Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Fixed charge coverage ratio that is required to be maintained	3.50
Restated credit agreement | LIBOR Loans | Senior Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Period of total debt to EBITDA ratio	12 months
Restated credit agreement | Base rate loans | Senior Credit Facility, net of original discount on borrowings and deferred financing costs | Base Rate
Debt Instrument [Line Items]
Interest rate margin on variable rate basis (in percentage)	0.50%
Restated credit agreement | Base rate loans | Senior Credit Facility, net of original discount on borrowings and deferred financing costs | LIBOR
Debt Instrument [Line Items]
Interest rate margin on variable rate basis (in percentage)	1.00%
Senior credit facility | Senior Credit Facility, net of original discount on borrowings and deferred financing costs
Debt Instrument [Line Items]
Weighted average interest rate on senior credit facility (in percentage)			3.40%	4.00%
Interest rate contract
Debt Instrument [Line Items]
Derivative term of contract		3 years
Notional amount		$ 222,300,000
LIBOR ceiling (in percentage)			2.50%