Basis of Presentation - Additional Information (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014 Location	May 31, 2013	Oct. 26, 2011
Basis Of Presentation [Line Items]
Number of locations	60
Percentage of common stock acquired		100.00%
Stock repurchase program, number of shares authorized to be repurchased			750,000
Stock repurchase program expiration date	Sep. 30, 2014
Minimum number of shares that company is required to repurchase	0
Stock repurchased under authorization	0
Impairment recorded	$ 0
Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	7
Abilene [Member]
Basis Of Presentation [Line Items]
Number of locations	11
Abilene [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Cleburne [Member]
Basis Of Presentation [Line Items]
Number of locations	2
Stephenville [Member]
Basis Of Presentation [Line Items]
Number of locations	2
Stephenville [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Granbury [Member]
Basis Of Presentation [Line Items]
Number of locations	2
San Angelo [Member]
Basis Of Presentation [Line Items]
Number of locations	3
San Angelo [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Weatherford [Member]
Basis Of Presentation [Line Items]
Number of locations	3
Mineral Wells [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Hereford [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Sweetwater [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Sweetwater [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Eastland [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Ranger [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Rising Star [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Cisco [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Southlake [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Grapevine [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Aledo [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Willow Park [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Brock [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Alvarado [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Burleson [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Keller [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Trophy Club [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Boyd [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Bridgeport [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Decatur [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Roby [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Trent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Merkel [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Clyde [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Moran [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Albany [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Midlothian [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Glen Rose [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Odessa [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Odessa [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Waxahachie [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Acton [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Fort Worth [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Fort Worth [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Orange [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Orange [Member] | Subsidiary of Common Parent [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Newton [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Port Arthur [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Vidor [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Mauriceville [Member]
Basis Of Presentation [Line Items]
Number of locations	1
Huntsville [Member]
Basis Of Presentation [Line Items]
Number of locations	1