Stockholders' Equity (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) Vote shares
Class of Stock [Line Items]
Shares reserved (in shares)	30,028,517
Revolving Credit Facility [Member]
Class of Stock [Line Items]
Restricted payments (annual limit) | $	$ 100,000
Restricted payments (total limit) | $	300,000
Restricted payments (rollover limit) | $	$ 25,000
Restricted payments pro forma ratio	2.50
Class B Convertible Common Stock [Member]
Class of Stock [Line Items]
Voting rights per share | Vote	10
Conversion feature	one-for-one
Shares reserved (in shares)	12,097,148
Common Stock [Member]
Class of Stock [Line Items]
Voting rights per share | Vote	1
Restricted stock units outstanding [Member]
Class of Stock [Line Items]
Shares reserved (in shares)	877,000
Available to grant 2007 Stock Incentive Program - [Member]
Class of Stock [Line Items]
Shares reserved (in shares)	1,975,000
Phantom stock units outstanding [Member]
Class of Stock [Line Items]
Shares reserved (in shares)	212,000
Convertible Senior Notes, Due 2025 [Member]
Class of Stock [Line Items]
Shares reserved (in shares)	14,867,369