Long-Term Debt (Narrative) (Details) - USD ($)				1 Months Ended		12 Months Ended
	Dec. 10, 2018	Aug. 07, 2018	Jul. 02, 2016	Nov. 30, 2016	Jul. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jul. 01, 2016
Disclosure Long Term Debt Additional Information [Line Items]
Proceeds from issuance of long-term debt						$ 107,607,000	$ 10,000,000	$ 132,000,000
Long-term debt						610,787,000	630,597,000
Debt Issuance Costs, Noncurrent						14,600,000
Deferred financing costs						100,000	900,000	300,000
Interest expense						57,100,000	55,100,000	46,200,000
Amortization of financing costs						$ 4,500,000	3,900,000	2,800,000
Debt instrument, covenant description						(a) in the event the consolidated total leverage ratio was at least 4.00:1.00, 75% thereof, (b) in the event the consolidated total leverage ratio was less than 4.00:1.00 but at least 3.00:1.00, 50% thereof and (c) in the event the consolidated total leverage ratio was less than 3.00:1.00, 0% thereof. The loans under the New Amended FS/KKR Credit Agreement will continue to amortize in quarterly installments of approximately $2.1 million.
Non cash interest expense						$ 400,000	$ 600,000	$ 800,000	$ 1,200,000
Interest Expense [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Deferred financing costs						500,000
Interest Rate Cap [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Derivative, notional amount				$ 500,000,000		$ 500,000,000
Derivative, cap interest rate						1.50%
Derivative, maturity date						Nov. 23, 2018
Benchmark LIBOR rate for repayment to company from financial institutions				1.50%
Interest Rate Swap [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Derivative, notional amount	$ 300,000,000					$ 300,000,000
Derivative, maturity date	Dec. 31, 2021
BoA Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument period of credit agreement		5 years
Proceeds from issuance of long-term debt		$ 335,000,000	$ 287,500,000
Long-term debt										$ 258,000,000
Debt instrument covenant payment percentage of intellectual property disposed liquidation value		50.00%
Debt instrument covenant payment percentage of net proceeds related to other assets constituting collateral		100.00%
Debt instrument orderly liquidation value of registered trademarks percentage benchmark		15.00%
Quarterly amortization installments						$ 5,000,000
Line of credit facility, covenant terms						The Amended BoA Credit Agreement contained customary representations and warranties and customary affirmative and negative covenants applicable to the BoA Facility Loan Parties and their subsidiaries. Moreover, the Amended BoA Credit Agreement contained financial covenants that required the BoA Facility Loan Parties and their subsidiaries to (i) maintain a positive net income (as defined), (ii) satisfy a maximum loan to value ratio set at 50.0% (applicable to the Revolving Loans and Tranche A Loans) and (iii) satisfy a maximum consolidated first lien leverage ratio, initially set at 2.80:1.00, decreasing over the term of the Amended BoA Credit Agreement until reaching the final maximum ratio of 2.50:1.00 for the fiscal quarter ending September 30, 2018 and thereafter
BoA Credit Agreement [Member] | Revolving Credit Facility [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Line of credit facility, maximum borrowing capacity										110,000,000
Line of credit facility, unused capacity, commitment fee percentage						0.375%
Debt instrument increase conditions						The Company could have requested an increase in (i) the Revolving Credit Facility and Tranche A Loans as would not have caused the consolidated first lien leverage ratio, determined on a pro forma basis after giving effect to any such increase, to exceed 2.33:1.00 and (ii) the Tranche A-1 Loans, as would not have caused the consolidated first lien leverage ratio, determined on a pro forma basis after giving effect to any such increase, to exceed (a) with respect to any increase, the proceeds of which will be used solely to finance an acquisition, 2.50:100 and (b) with respect to any other increase, 2.40:1.00, subject to the satisfaction of certain conditions in the Amended BoA Credit Agreement
Long-term Line of Credit										80,500,000
BoA Credit Agreement [Member] | Tranche A -1 Term Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, face amount										44,500,000
Long-term debt										44,500,000
BoA Credit Agreement [Member] | Tranche A -1 Term Loans [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						7.00%
BoA Credit Agreement [Member] | Tranche A -1 Term Loans [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						6.00%
BoA Credit Agreement [Member] | Tranche A [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, face amount										133,000,000
Long-term debt										133,000,000
BoA Credit Agreement [Member] | Tranche A [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate					3.50%
BoA Credit Agreement [Member] | Tranche A [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						2.50%
BoA Term Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Long-term debt						$ 5,000,000
Tranche A [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Maximum loan to value ratio						50.00%
Tranche A [Member] | Revolving Credit Facility [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio		2.80%
Tranche A -1 Term Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						3.00%
Revolving Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Long-term debt		$ 115,000,000
GSO Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Line of credit facility, maximum borrowing capacity										415,000,000
Line of credit facility, covenant terms						The Amended FS/KKR Credit Agreement contained customary representations and warranties and customary affirmative and negative covenants applicable to the FS/KKR Facility Loan Parties and their subsidiaries. Moreover, the Amended FS/KKR Credit Agreement contained financial covenants that require the GSO Facility Loan Parties and their subsidiaries to satisfy (i) a maximum consolidated total leverage ratio, initially set at 7.25:1.00, decreasing over the term of the Amended FS/KKR Credit Agreement until reaching the final maximum ratio of 6.50:1.00 for the fiscal quarter ending September 30, 2018 and thereafter and (ii) a maximum consolidated first lien leverage ratio, initially set at 2.80:1.00, decreasing over the term of the Amended FS/KKR Credit Agreement until reaching the final maximum ratio of 2.50:1.00 for the fiscal quarter ending September 30, 2018 and thereafter
Amended KKR Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Line of credit facility, maximum borrowing capacity										$ 415,000,000
Debt instrument increase conditions						The Company could have requested one or more additional term loan facilities or the increase of term loan commitments under the Amended FS/KKR Credit Agreement as would not have caused the consolidated total leverage ratio, determined on a pro forma basis after giving effect to any such addition and increase, to exceed 6.00:1.00, subject to the satisfaction of certain conditions in the Amended FS/KKR Credit Agreement
Amended KKR Credit Agreement [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of consolidated excess cash flow for mandatory prepayment						75.00%
Amended KKR Credit Agreement [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of consolidated excess cash flow for mandatory prepayment						50.00%
Amended KKR Credit Agreement [Member] | Scenario Plan Three [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of consolidated excess cash flow for mandatory prepayment						0.00%
Amended FS/KKR Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of disposed intellectual property for mandatory prepayment						50.00%
Percent of assets disposed of other than intellectual property for mandatory prepayment						100.00%
Annual amortization as a percent of original aggregate principal						2.00%
Amended FS/KKR Credit Agreement [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of consolidated excess cash flow for mandatory prepayment						75.00%
Amended FS/KKR Credit Agreement [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of consolidated excess cash flow for mandatory prepayment						50.00%
Amended FS/KKR Credit Agreement [Member] | Scenario Plan Three [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of consolidated excess cash flow for mandatory prepayment						0.00%
FS/KKR Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, face amount		314,000,000
Debt instrument, periodic payment		$ 2,100,000
Debt instrument, covenant description		(i) a maximum consolidated total leverage ratio, initially set at 7.25:1.00, decreasing over the term of the New Amended FS/KKR Credit Agreement until reaching a final maximum ratio of 6.25:1.00 for the fiscal quarter ending September 30, 2022 and thereafter and (ii) a maximum consolidated first lien leverage ratio, initially set at 3.875:1.00, decreasing over the term of the New Amended FS/KKR Credit Agreement until reaching a final maximum ratio of 2.875:1.00 for the fiscal quarter ending September 30, 2022 and thereafter
Debt instrument consolidated total leverage ratio		6.00%
FS/KKR Credit Agreement [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		8.75%
FS/KKR Credit Agreement [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		7.75%
New Amended FS/KKR Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Percent of disposed intellectual property for mandatory prepayment						50.00%
Percent of assets disposed of other than intellectual property for mandatory prepayment						100.00%
New Amended FS/KKR Credit Agreement [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						3.875%
Final consolidated total leverage ratio						7.25%
New Amended FS/KKR Credit Agreement [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.875%
Final consolidated total leverage ratio						6.25%
New Amended FS/KKR Credit Agreement [Member] | Scenario Plan Three [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated total leverage ratio						6.00%
Amended GSO Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument increase conditions						The Company may request one or more additional term loan facilities or the increase of term loan commitments under the Amended GSO Credit Agreement as would not cause the consolidated total leverage ratio, determined on a pro forma basis after giving effect to any such addition and increase, to exceed 6.00:1.00, subject to the satisfaction of certain conditions in the Amended GSO Credit Agreement
Third Amended BoA Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Long-term debt		$ 335,000,000
Amended BoA Revolving Credit Commitments [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, face amount		$ 130,000,000
Maximum loan to value ratio						50.00%
Consolidated first lien leverage ratio		3.875%
Final consolidated first lien leverage ratio		2.875%
Final consolidated first lien leverage ratio		2.875%
Percent of disposed intellectual property for mandatory prepayment						50.00%
Percent of assets disposed of other than intellectual property for mandatory prepayment						100.00%
Line of Credit Facility, Commitment Fee Percentage		0.375%
Amended BoA Revolving Credit Commitments [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.80%
Amended BoA Revolving Credit Commitments [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Final consolidated first lien leverage ratio						2.50%
Final consolidated first lien leverage ratio						2.50%
Third Amended BoA Tranche A-1 Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Long-term debt		$ 70,000,000
Third Amended BoA Tranche A-1 Loans [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		7.00%
Third Amended BoA Tranche A-1 Loans [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		6.00%
Amended BoA Revolving Loans and Amended Tranche A Loans [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						3.50%
Amended BoA Revolving Loans and Amended Tranche A Loans [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						2.50%
Third Amended BoA Tranche A Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, face amount		$ 150,000,000
Long-term debt		$ 150,000,000
New Amended BoA Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.90%
Amended FS/KKR Covenant Requirements - GSO Facility Loan Parties [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						7.25%
Final consolidated first lien leverage ratio						6.50%
Final consolidated first lien leverage ratio						6.50%
Amended FS/KKR Covenant Requirements - GSO Facility Loan Parties [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.80%
Final consolidated first lien leverage ratio						2.50%
Final consolidated first lien leverage ratio						2.50%
Maximum [Member] | Tranche A -1 Term Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument orderly liquidation value of registered trademarks percentage benchmark						10.00%
Maximum [Member] | Tranche A -1 Term Loans [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.50%
Maximum [Member] | Tranche A -1 Term Loans [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.40%
Maximum [Member] | Amended KKR Credit Agreement [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument consolidated total leverage ratio						4.00%
Maximum [Member] | Amended KKR Credit Agreement [Member] | Scenario Plan Three [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument consolidated total leverage ratio						3.00%
Maximum [Member] | Amended KKR Credit Agreement [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						9.00%
Maximum [Member] | Amended KKR Credit Agreement [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						8.00%
Maximum [Member] | Amended FS/KKR Credit Agreement [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated total leverage ratio						4.00%
Maximum [Member] | Amended FS/KKR Credit Agreement [Member] | Scenario Plan Three [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated total leverage ratio						3.00%
Maximum [Member] | Amended FS/KKR Credit Agreement [Member] | Scenario Plan Four [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated total leverage ratio						6.00%
Maximum [Member] | Third Amended BoA Credit Agreement [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Maximum loan to value ratio		42.50%
Maximum [Member] | Third Amended BoA Tranche A-1 Loans [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		6.00%
Maximum [Member] | Third Amended BoA Tranche A-1 Loans [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		5.00%
Maximum [Member] | Amended BoA Revolving Loans and Amended Tranche A Loans [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		3.00%
Maximum [Member] | Amended BoA Revolving Loans and Amended Tranche A Loans [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate		2.00%
Maximum [Member] | Revolving Credit Facility and Tranche A Loans [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated first lien leverage ratio						2.33%
Minimum [Member] | Amended KKR Credit Agreement [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument consolidated total leverage ratio		4.00%
Minimum [Member] | Amended KKR Credit Agreement [Member] | Scenario Plan Three [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument consolidated total leverage ratio		3.00%
Minimum [Member] | Amended KKR Credit Agreement [Member] | London Interbank Offered Rate (LIBOR) [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						8.25%
Minimum [Member] | Amended KKR Credit Agreement [Member] | Base Rate [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Debt instrument, basis spread on variable rate						7.25%
Minimum [Member] | Amended FS/KKR Credit Agreement [Member] | Scenario Plan One [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated total leverage ratio						4.00%
Minimum [Member] | Amended FS/KKR Credit Agreement [Member] | Scenario Plan Two [Member]
Disclosure Long Term Debt Additional Information [Line Items]
Consolidated total leverage ratio						3.00%