Condensed Consolidating Financial Statements (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 25, 2013	Jun. 26, 2012	Jun. 25, 2013	Jun. 26, 2012
Condensed Consolidating Statements of Income
Total sales	$ 261,958	$ 263,561	$ 540,927	$ 533,975
Total costs and expenses	241,044	242,839	494,162	488,377
Operating income	20,914	20,722	46,765	45,598
Interest expense	10,237	11,467	20,477	24,381
Gains (Losses) on Extinguishment of Debt	0	(5,144)	0	5,144
Equity in net income of subsidiary		0	0	0
Income before income taxes	10,677	4,111	26,288	16,073
Income tax expense	2,589	1,122	4,956	4,079
Net income	8,088	2,989	21,332	11,994
Parent Guarantor: Holdings [Member]
Condensed Consolidating Statements of Income
Total sales		0	0	0
Total costs and expenses		0	0	0
Operating income		0	0	0
Interest expense		0	0	0
Gains (Losses) on Extinguishment of Debt		0		0
Equity in net income of subsidiary	8,088	2,989	21,332	11,994
Income before income taxes	8,088	2,989	21,332	11,994
Income tax expense	0	0	0	0
Net income	8,088	2,989	21,332	11,994
Subsidiary Issuer: NPC [Member]
Condensed Consolidating Statements of Income
Total sales	261,958	263,561	540,927	533,975
Total costs and expenses	241,044	242,839	494,162	488,377
Operating income	20,914	20,722	46,765	45,598
Interest expense	10,237	11,467	20,477	24,381
Gains (Losses) on Extinguishment of Debt		(5,144)		(5,144)
Equity in net income of subsidiary		0	0	0
Income before income taxes	10,677	4,111	26,288	16,073
Income tax expense	2,589	1,122	4,956	4,079
Net income	8,088	2,989	21,332	11,994
Subsidiary Co-Issuer: NPC Op Co A [Member]
Condensed Consolidating Statements of Income
Total sales		0	0	0
Total costs and expenses		0	0	0
Operating income		0	0	0
Interest expense		0	0	0
Gains (Losses) on Extinguishment of Debt		0		0
Equity in net income of subsidiary		0	0	0
Income before income taxes		0	0	0
Income tax expense		0	0	0
Net income		0	0	0
Subsidiary Co-Issuer: NPC Op Co B [Member]
Condensed Consolidating Statements of Income
Total sales		0	0	0
Total costs and expenses		0	0	0
Operating income		0	0	0
Interest expense		0	0	0
Gains (Losses) on Extinguishment of Debt		0		0
Equity in net income of subsidiary		0	0	0
Income before income taxes		0	0	0
Income tax expense		0	0	0
Net income		0	0	0
Eliminations [Member]
Condensed Consolidating Statements of Income
Total sales		0	0	0
Total costs and expenses		0	0	0
Operating income		0	0	0
Interest expense		0	0	0
Gains (Losses) on Extinguishment of Debt		0		0
Equity in net income of subsidiary	(8,088)	(2,989)	(21,332)	(11,994)
Income before income taxes	(8,088)	(2,989)	(21,332)	(11,994)
Income tax expense	0	0	0	0
Net income	$ (8,088)	$ (2,989)	$ (21,332)	$ (11,994)