Revision to Correct Immaterial Error in Previously Issued Financial Statements Restatement Adjustments (Details) - USD ($)	3 Months Ended										6 Months Ended			9 Months Ended		12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Selling, general and administrative expenses	$ 51,418,000	$ 51,492,000	$ 52,456,000	$ 48,787,000	$ 47,134,000	$ 48,915,000	$ 49,904,000	$ 47,478,000	$ 48,500,000	$ 50,307,000	$ 102,910,000	$ 96,049,000	$ 98,807,000	$ 144,836,000	$ 146,286,000	$ 197,291,000	$ 196,190,000	$ 183,600,000
Income (Loss) from operations	1,056,000	603,000	(31,379,000)	9,638,000	6,903,000	1,745,000	37,573,000	6,803,000	5,531,000	802,000	1,659,000	8,649,000	6,333,000	18,287,000	13,136,000	(13,093,000)	50,709,000	(6,137,000)
Income (Loss) before taxes	386,000	(621,000)	(34,738,000)	7,423,000	5,838,000	705,000	35,810,000	5,622,000	4,474,000	(314,000)	(235,000)	6,543,000	4,160,000	13,968,000	9,781,000	(20,771,000)	45,591,000	(9,372,000)
Income tax expense (benefit)	2,710,000	2,072,000	6,192,000	3,487,000	2,183,000	430,000	(844,000)	1,395,000	1,403,000	(98,000)	4,782,000	2,613,000	1,304,000	6,100,000	2,700,000	12,292,000	1,855,000	(612,000)
Net income (loss)	$ (2,324,000)	$ (2,693,000)	$ (40,929,000)	$ 3,936,000	$ 3,655,000	$ 275,000	$ 36,655,000	$ 4,227,000	$ 3,071,000	$ (216,000)	$ (5,017,000)	$ 3,930,000	$ 2,856,000	$ 7,868,000	$ 7,081,000	$ (33,063,000)	$ 43,736,000	$ (8,760,000)
Net income (loss) per share:
Basic earnings (loss) per share (in usd per share)	$ (0.04)	$ (0.05)	$ (0.77)	$ 0.07	$ 0.07	$ 0.01	$ 0.69	$ 0.08	$ 0.06	$ 0	$ (0.09)	$ 0.07	$ 0.06	$ 0.15	$ 0.14	$ (0.63)	$ 0.84	$ (0.17)
Diluted earnings (loss) per share (in usd per share)	$ (0.04)	$ (0.05)	$ (0.77)	$ 0.07	$ 0.07	$ 0.01	$ 0.68	$ 0.08	$ 0.06	$ 0	$ (0.09)	$ 0.07	$ 0.05	$ 0.15	$ 0.13	$ (0.63)	$ 0.82	$ (0.17)
Comprehensive income (loss)	$ (3,714,000)	$ (3,163,000)	$ (43,312,000)	$ 2,072,000	$ 5,753,000	$ (6,167,000)	$ 32,241,000	$ (362,000)	$ 3,578,000	$ 100,000	$ (6,877,000)	$ (414,000)	$ 3,679,000	$ 1,658,000	$ 3,317,000	$ (41,654,000)	$ 35,558,000	$ (6,257,000)
Statement of Financial Position [Abstract]
Deferred income taxes				3,926,000	3,186,000	4,254,000	3,818,000	2,713,000	2,207,000	2,759,000		3,186,000	2,207,000	3,926,000	2,713,000		3,818,000	2,660,000
Total current assets	318,453,000		329,837,000	337,648,000	317,533,000	303,582,000	306,227,000	328,757,000	312,546,000	301,849,000	318,453,000	317,533,000	312,546,000	337,648,000	328,757,000	329,837,000	306,227,000	281,212,000
Total assets	593,567,000		608,467,000	662,513,000	643,003,000	626,432,000	633,250,000	661,098,000	649,692,000	639,495,000	593,567,000	643,003,000	649,692,000	662,513,000	661,098,000	608,467,000	633,250,000	616,208,000
Accrued expenses	17,818,000	24,257,000	17,866,000	15,584,000	12,843,000	17,196,000	15,156,000	20,132,000	14,498,000	21,920,000	17,818,000	12,843,000	14,498,000	15,584,000	20,132,000	17,866,000	15,156,000	21,100,000
Total current liabilities	202,460,000	204,416,000	231,262,000	213,092,000	206,535,000	197,017,000	199,318,000	235,674,000	248,254,000	241,157,000	202,460,000	206,535,000	248,254,000	213,092,000	235,674,000	231,262,000	199,318,000	222,881,000
Deferred income taxes	11,620,000	10,476,000	10,526,000								11,620,000					10,526,000
Total liabilities	342,984,000	345,466,000	354,331,000	367,176,000	350,878,000	340,894,000	340,270,000	401,671,000	398,689,000	395,227,000	342,984,000	350,878,000	398,689,000	367,176,000	401,671,000	354,331,000	340,270,000	373,208,000
Retained earnings	101,614,000	104,071,000	106,764,000	148,536,000	144,598,000	141,217,000	140,942,000	104,287,000	102,287,000	100,272,000	101,614,000	144,598,000	102,287,000	148,536,000	104,287,000	106,764,000	140,942,000	100,487,000
Total stockholders' equity	250,583,000	253,130,000	254,136,000	295,337,000	292,125,000	285,538,000	292,980,000	259,427,000	251,003,000	244,268,000	250,583,000	292,125,000	251,003,000	295,337,000	259,427,000	254,136,000	292,980,000	243,000,000
Total liabilities and stockholders' equity	593,567,000	598,596,000	608,467,000	662,513,000	643,003,000	626,432,000	633,250,000	661,098,000	649,692,000	639,495,000	593,567,000	643,003,000	649,692,000	662,513,000	661,098,000	608,467,000	633,250,000	616,208,000
Statement of Cash Flows [Abstract]
Net income (loss)	$ (2,324,000)	(2,693,000)	(40,929,000)	3,936,000	3,655,000	275,000	36,655,000	4,227,000	3,071,000	(216,000)	(5,017,000)	3,930,000	2,856,000	7,868,000	7,081,000	(33,063,000)	43,736,000	(8,760,000)
Deferred income taxes		(389,000)			1,366,141	(412,000)				(178,000)	449,670	1,366,000	853,000	768,000	1,244,000	6,947,000	(2,649,000)	(708,000)
Accrued expenses and other liabilities		11,518,000			(3,974,365)	(2,339,000)				4,108,000	4,632,392	(3,974,000)	3,627,000	2,989,000	7,297,000	2,118,000	3,345,000	(11,965,000)
Net cash provided by (used in) operating activities		(24,566,000)			987,003	(6,275,000)				(8,408,000)	$ (848,205)	988,000	(4,188,000)	(7,257,000)	(16,038,000)	43,402,000	(12,515,000)	37,371,000
As Reported
Statement of Comprehensive Income [Abstract]
Selling, general and administrative expenses		50,627,000	50,890,000	47,221,000	50,437,000	47,647,000	48,613,000	46,187,000	50,634,000	49,571,000		98,084,000	100,206,000	145,305,000	146,393,000	196,194,000	195,006,000	183,443,000
Income (Loss) from operations		1,468,000	(29,813,000)	11,204,000	3,600,000	3,013,000	38,864,000	8,094,000	3,397,000	1,537,000		6,614,000	4,934,000	17,818,000	13,029,000	(11,996,000)	51,893,000	(5,981,000)
Income (Loss) before taxes		244,000	(33,172,000)	8,989,000	2,535,000	1,973,000	37,101,000	6,913,000	2,340,000	422,000		4,508,000	2,761,000	13,499,000	9,674,000	(19,673,000)	46,775,000	(9,216,000)
Income tax expense (benefit)		2,393,000	6,720,000	4,007,000	1,104,000	834,000	(351,000)	1,799,000	733,000	132,000		1,939,000	865,000	5,946,000	2,665,000	12,665,000	2,313,000	(556,000)
Net income (loss)		$ (2,149,000)	$ (39,891,000)	$ 4,982,000	$ 1,431,000	$ 1,139,000	$ 37,454,000	$ 5,114,000	$ 1,605,000	$ 290,000		$ 2,570,000	$ 1,896,000	$ 7,553,000	$ 7,009,000	$ (32,338,000)	$ 44,462,000	$ (8,660,000)
Net income (loss) per share:
Basic earnings (loss) per share (in usd per share)		$ (0.04)	$ (0.75)	$ 0.09	$ 0.03	$ 0.02	$ 0.71	$ 0.10	$ 0.03	$ 0		$ 0.05	$ 0.04	$ 0.14	$ 0.13	$ (0.61)	$ 0.85	$ (0.17)
Diluted earnings (loss) per share (in usd per share)		$ (0.04)	$ (0.75)	$ 0.09	$ 0.03	$ 0.02	$ 0.69	$ 0.10	$ 0.03	$ 0		$ 0.05	$ 0.04	$ 0.14	$ 0.13	$ (0.61)	$ 0.84	$ (0.17)
Comprehensive income (loss)		$ (2,619,000)	$ (42,274,000)	$ 3,118,000	$ 3,529,000	$ (5,303,000)	$ 33,040,000	$ 525,000	$ 2,113,000	$ 605,000		$ (1,774,000)	$ 2,718,000	$ 1,344,000	$ 3,244,000	$ (40,930,000)	$ 36,284,000	$ (6,156,000)
Statement of Financial Position [Abstract]
Deferred income taxes				2,082,000	1,861,000	1,850,000	1,819,000	1,207,000	1,105,000	987,000		1,861,000	1,105,000	2,082,000	1,207,000		1,819,000	1,119,000
Total current assets				335,804,000	316,208,000	301,178,000	304,228,000	327,251,000	311,444,000	300,077,000		316,208,000	311,444,000	335,804,000	327,251,000		304,228,000	279,671,000
Total assets				660,669,000	641,678,000	624,028,000	631,251,000	659,592,000	648,590,000	637,723,000		641,678,000	648,590,000	660,669,000	659,592,000		631,251,000	614,667,000
Accrued expenses		17,129,000	11,603,000	10,887,000	9,710,000	10,762,000	9,990,000	16,258,000	11,915,000	17,203,000		9,710,000	11,915,000	10,887,000	16,258,000	11,603,000	9,990,000	17,118,000
Total current liabilities		197,288,000	224,999,000	208,395,000	203,404,000	190,583,000	194,152,000	231,800,000	245,671,000	236,440,000		203,404,000	245,671,000	208,395,000	231,800,000	224,999,000	194,152,000	218,899,000
Deferred income taxes		13,168,000	12,898,000													12,898,000
Total liabilities		341,031,000	350,440,000	362,479,000	347,747,000	334,460,000	335,104,000	397,797,000	396,106,000	390,510,000		347,747,000	396,106,000	362,479,000	397,797,000	350,440,000	335,104,000	369,226,000
Retained earnings		108,506,000	110,655,000	151,389,000	146,405,000	145,247,000	144,109,000	106,655,000	103,768,000	103,218,000		146,405,000	103,768,000	151,389,000	106,655,000	110,655,000	144,109,000	102,928,000
Total stockholders' equity		257,565,000	258,027,000	298,190,000	293,932,000	289,568,000	296,147,000	261,795,000	252,484,000	247,214,000		293,932,000	252,484,000	298,190,000	261,795,000	258,027,000	296,147,000	245,441,000
Total liabilities and stockholders' equity		598,596,000	608,467,000	660,669,000	641,678,000	624,029,000	631,251,000	659,592,000	648,590,000	637,724,000		641,678,000	648,590,000	660,669,000	659,592,000	608,467,000	631,251,000	614,667,000
Statement of Cash Flows [Abstract]
Net income (loss)		(2,149,000)	(39,891,000)	4,982,000	1,431,000	1,139,000	37,454,000	5,114,000	1,605,000	290,000		2,570,000	1,896,000	7,553,000	7,009,000	(32,338,000)	44,462,000	(8,660,000)
Deferred income taxes		(68,000)				(7,000)				53,000		692,000	414,000	613,000	1,209,000	7,320,000	(2,192,000)	(653,000)
Accrued expenses and other liabilities		10,653,000				(3,608,000)				3,371,000		(1,940,000)	5,026,000	3,459,000	7,404,000	1,021,000	2,162,000	(12,121,000)
Net cash provided by (used in) operating activities		(24,566,000)				(6,275,000)				(8,408,000)		988,000	(4,188,000)	(7,257,000)	(16,038,000)	43,402,000	(12,515,000)	37,371,000
Adjustments
Statement of Comprehensive Income [Abstract]
Selling, general and administrative expenses		865,000	1,566,000	1,566,000	(3,303,000)	1,268,000	1,291,000	1,291,000	(2,134,000)	736,000		(2,035,000)	(1,399,000)	(469,000)	(107,000)	1,097,000	1,184,000	157,000
Income (Loss) from operations		(865,000)	(1,566,000)	(1,566,000)	3,303,000	(1,268,000)	(1,291,000)	(1,291,000)	2,134,000	(736,000)		2,035,000	1,399,000	469,000	107,000	(1,097,000)	(1,184,000)	(157,000)
Income (Loss) before taxes		(865,000)	(1,566,000)	(1,566,000)	3,303,000	(1,268,000)	(1,291,000)	(1,291,000)	2,134,000	(736,000)		2,035,000	1,399,000	469,000	107,000	(1,097,000)	(1,184,000)	(157,000)
Income tax expense (benefit)		(321,000)	(528,000)	(520,000)	1,079,000	(405,000)	(493,000)	(404,000)	670,000	(231,000)		674,000	439,000	154,000	35,000	(373,000)	(458,000)	(56,000)
Net income (loss)		$ (544,000)	$ (1,038,000)	$ (1,046,000)	$ 2,224,000	$ (864,000)	$ (799,000)	$ (887,000)	$ 1,465,000	$ (505,000)		$ 1,360,000	$ 960,000	$ 314,000	$ 73,000	$ (724,000)	$ (726,000)	$ (101,000)
Net income (loss) per share:
Basic earnings (loss) per share (in usd per share)		$ (0.01)	$ (0.02)	$ (0.02)	$ 0.04	$ (0.01)	$ (0.02)	$ (0.02)	$ 0.03	$ 0		$ 0.02	$ 0.02	$ 0.01	$ 0.01	$ (0.02)	$ (0.01)	$ 0.00
Diluted earnings (loss) per share (in usd per share)		$ (0.01)	$ (0.02)	$ (0.02)	$ 0.04	$ (0.01)	$ (0.01)	$ (0.02)	$ 0.03	$ 0		$ 0.02	$ 0.01	$ 0.01	$ 0.00	$ (0.02)	$ (0.02)	$ 0.00
Comprehensive income (loss)		$ (544,000)	$ (1,038,000)	$ (1,046,000)	$ 2,224,000	$ (864,000)	$ (799,000)	$ (887,000)	$ 1,465,000	$ (505,000)		$ 1,360,000	$ 960,000	$ 314,000	$ 73,000	$ (724,000)	$ (726,000)	$ (101,000)
Statement of Financial Position [Abstract]
Deferred income taxes				1,844,000	1,325,000	2,404,000	1,999,000	1,506,000	1,102,000	1,772,000		1,325,000	1,102,000	1,844,000	1,506,000		1,999,000	1,541,000
Total current assets				1,844,000	1,325,000	2,404,000	1,999,000	1,506,000	1,102,000	1,772,000		1,325,000	1,102,000	1,844,000	1,506,000		1,999,000	1,541,000
Total assets				1,844,000	1,325,000	2,404,000	1,999,000	1,506,000	1,102,000	1,772,000		1,325,000	1,102,000	1,844,000	1,506,000		1,999,000	1,541,000
Accrued expenses		7,128,000	6,263,000	4,697,000	3,131,000	6,434,000	5,166,000	3,874,000	2,583,000	4,717,000		3,131,000	2,583,000	4,697,000	3,874,000	6,263,000	5,166,000	3,982,000
Total current liabilities		7,128,000	6,263,000	4,697,000	3,131,000	6,434,000	5,166,000	3,874,000	2,583,000	4,717,000		3,131,000	2,583,000	4,697,000	3,874,000	6,263,000	5,166,000	3,982,000
Deferred income taxes		(2,692,000)	(2,372,000)													(2,372,000)
Total liabilities		4,435,000	3,891,000	4,697,000	3,131,000	6,434,000	5,166,000	3,874,000	2,583,000	4,717,000		3,131,000	2,583,000	4,697,000	3,874,000	3,891,000	5,166,000	3,982,000
Retained earnings		(4,435,000)	(3,891,000)	(2,853,000)	(1,807,000)	(4,030,000)	(3,167,000)	(2,368,000)	(1,481,000)	(2,946,000)		(1,807,000)	(1,481,000)	(2,853,000)	(2,368,000)	(3,891,000)	(3,167,000)	(2,441,000)
Total stockholders' equity		(4,435,000)	(3,891,000)	(2,853,000)	(1,807,000)	(4,030,000)	(3,167,000)	(2,368,000)	(1,481,000)	(2,946,000)		(1,807,000)	(1,481,000)	(2,853,000)	(2,368,000)	(3,891,000)	(3,167,000)	(2,441,000)
Total liabilities and stockholders' equity		0	0	1,844,000	1,325,000	2,404,000	1,999,000	1,506,000	1,102,000	1,771,000		1,325,000	1,102,000	1,844,000	1,506,000	0	1,999,000	1,541,000
Statement of Cash Flows [Abstract]
Net income (loss)		(544,000)	$ (1,038,000)	$ (1,046,000)	$ 2,224,000	(864,000)	$ (799,000)	$ (887,000)	$ 1,465,000	(505,000)		1,360,000	960,000	314,000	73,000	(724,000)	(726,000)	(101,000)
Deferred income taxes		(321,000)				(405,000)				(231,000)		674,000	439,000	155,000	35,000	(373,000)	(457,000)	(55,000)
Accrued expenses and other liabilities		865,000				1,269,000				737,000		(2,034,000)	(1,399,000)	(470,000)	(107,000)	1,097,000	1,183,000	156,000
Net cash provided by (used in) operating activities		$ 0				$ 0				$ 0		$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0