Organization and Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Recent Accounting Pronouncement
Package of practical expedients		true
Assets
Other current assets	$ 12,961	$ 13,673	$ 18,731
Total current assets	320,130	315,655	325,900
Property, plant and equipment, net	81,421	84,057	89,489
Other intangible assets, net	15,258	17,952	15,478
Deferred income taxes	65,051	70,481	65,635
Operating lease right-of-use assets	102,226	110,559
Other assets	8,304	11,305	7,766
Total assets	791,132	842,253	703,010
Current liabilities:
Current portion of long-term debt	7,964	8,752	8,583
Accrued expenses and other current liabilities	50,431	55,825	51,783
Current portion of operating lease liabilities	31,479	34,342
Total current liabilities	200,782	208,406	171,274
Long-term liabilities:
Long-term debt, less current portion	489,597	490,121	502,090
Operating lease liabilities	82,510	88,418
Other liabilities	38,620	45,804	51,570
Total liabilities	811,509	832,749	724,934
Shareholders' deficit:
Accumulated deficit	(359,476)	(331,951)	(361,023)
Total shareholders' deficit	(20,377)	9,504	(21,924)	$ (28,807)	$ (28,051)	$ 65,414
Total liabilities and shareholders' deficit	791,132	842,253	703,010
Deferred tax asset	65,051	70,481	$ 65,635
Capitalized implementation costs		1,964
ASU 2014-09
Assets
Deferred income taxes				300
Shareholders' deficit:
Accumulated deficit				(800)
Contract liability				1,000
Deferred tax asset				$ 300
ASU 2016-02
Recent Accounting Pronouncement
Accumulated deficit recognized	1,500
ASU 2018-15
Shareholders' deficit:
Capitalized implementation costs		$ 2,100
Restatement Adjustments | ASU 2016-02
Assets
Other current assets	(5,770)
Total current assets	(5,770)
Property, plant and equipment, net	(8,068)
Other intangible assets, net	(220)
Deferred income taxes	(584)
Operating lease right-of-use assets	102,226
Other assets	538
Total assets	88,122
Current liabilities:
Current portion of long-term debt	(619)
Accrued expenses and other current liabilities	(1,352)
Current portion of operating lease liabilities	31,479
Total current liabilities	29,508
Long-term liabilities:
Long-term debt, less current portion	(12,493)
Operating lease liabilities	82,510
Other liabilities	(12,950)
Total liabilities	86,575
Shareholders' deficit:
Accumulated deficit	1,547
Total shareholders' deficit	1,547
Total liabilities and shareholders' deficit	88,122
Deferred tax asset	$ (584)