Commitments - Additional Information (Detail) $ in Thousands						1 Months Ended								12 Months Ended
	Oct. 12, 2015 T	Nov. 13, 2014 T	Nov. 30, 2012 USD ($)	Jan. 30, 2012 T	Nov. 01, 2008 USD ($)	Nov. 30, 2017 T	Sep. 30, 2017 T	Jun. 30, 2017 T	Apr. 30, 2017 T	Oct. 31, 2014	May 31, 2012	Jul. 31, 2011 T	Jan. 31, 2003	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2011	Nov. 30, 2015
Long-term Purchase Commitment [Line Items]
Annual rental fee | $														$ 20,310	$ 22,040	$ 23,757
Net book value of property leased | $														324,186	494,103
Lease Agreements
Long-term Purchase Commitment [Line Items]
Net book value of property leased | $														262,319
Eufaula | kaolin | Supplier 2
Long-term Purchase Commitment [Line Items]
Commitment effective date																	Jan. 01, 2011
Purchase commitment, period																	3 years
Additional purchase commitment, period																	6 years
Purchase commitment amount | $														$ 2,207	968	$ 2,380
Eufaula | kaolin | Supplier 2 | After Amendment
Long-term Purchase Commitment [Line Items]
Additional purchase commitment, period											3 years
Eufaula | Minimum | kaolin | Supplier 2
Long-term Purchase Commitment [Line Items]
Purchase obligation percentage of annual requirements																	70.00%
Eufaula | Minimum | kaolin | Supplier 2 | After Amendment
Long-term Purchase Commitment [Line Items]
Purchase commitment, period											5 years
Purchase obligation percentage of annual requirements											50.00%
McIntyre | Lease Agreements
Long-term Purchase Commitment [Line Items]
Lease expiration period																Jan. 01, 2021
McIntyre | Wilkinson County Development Authority
Long-term Purchase Commitment [Line Items]
Agreement entry date					Nov. 01, 2008
Annual rental fee | $					$ 50
Lease agreement period														Through November 1, 2017
McIntyre | kaolin | Supplier 3
Long-term Purchase Commitment [Line Items]
Commitment effective date													Jan. 01, 2003
Purchase commitment amount | $														$ 950	1,196	$ 3,245
Agreement entry date													Jan. 01, 2003
McIntyre | Minimum | kaolin | Supplier 3
Long-term Purchase Commitment [Line Items]
Purchase obligation percentage of annual requirements													80.00%
McIntyre And Toomsboro [Member] | kaolin | Supplier 3
Long-term Purchase Commitment [Line Items]
Purchase obligation percentage of annual requirements																		100.00%
Marshfield, Wisconsin | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Purchase commitment amount | $														3,876	0	3,997
Minimum quantity to be purchased annually								360,000
Additional Minimum Purchase Requirements								0
Marshfield, Wisconsin | Frac sand
Long-term Purchase Commitment [Line Items]
Purchase commitment amount | $														3,837	252	1,751
Marshfield, Wisconsin | After Amendment | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Purchase commitment, commencing date				Jan. 30, 2012
Marshfield, Wisconsin | Prior Agreement | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Commitment effective date												Jul. 30, 2011
Purchase commitment, period												5 years
Marshfield, Wisconsin | Agreement on September 2017 | Frac sand
Long-term Purchase Commitment [Line Items]
Purchase commitment amount | $														675
Marshfield, Wisconsin | Agreement on November 2017 | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Purchase commitment amount | $														$ 0
Minimum quantity to be purchased annually						40,000
Marshfield, Wisconsin | During 2011 | Prior Agreement | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually												40,000
Marshfield, Wisconsin | During 2012 | After Amendment | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually				150,000
Marshfield, Wisconsin | During 2012 | Prior Agreement | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually												100,000
Marshfield, Wisconsin | During 2013 | After Amendment | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually				150,000
Marshfield, Wisconsin | During 2014 | After Amendment | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually				350,000
Marshfield, Wisconsin | During 2015 | After Amendment | Hydro sized sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually				0
Marshfield, Wisconsin | During 2015 | After Amendment | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually	123,203
Marshfield, Wisconsin | During 2015 | Prior Agreement | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually		300,000
Marshfield, Wisconsin | Each year after 2015 | Prior Agreement | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually		400,000
Marshfield, Wisconsin | During 2016 | After Amendment | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually	116,599
Marshfield, Wisconsin | During 2017 | After Amendment | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually									400,000
Marshfield, Wisconsin | 2018 and thereafter | After Amendment | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually									400,000
Marshfield, Wisconsin | Through February 2018 | Agreement on September 2017 | Frac sand
Long-term Purchase Commitment [Line Items]
Minimum quantity to be purchased annually							16,000
Millen Georgia | Jenkins County Development Authority
Long-term Purchase Commitment [Line Items]
Agreement entry date			Nov. 01, 2012
Lease agreement period														Until the tenth anniversary of completion of the final phase of the facility.
Lease administrative fees | $			$ 50
Millen Georgia | Kaolin And Bauxite | Supplier 7
Long-term Purchase Commitment [Line Items]
Purchase commitment, period											5 years
Additional purchase commitment, period											5 years
Purchase commitment amount | $														$ 0	0	561
Agreement entry date											May 31, 2012
Millen Georgia | Kaolin And Bauxite | Supplier 8
Long-term Purchase Commitment [Line Items]
Purchase commitment, period										5 years
Additional purchase commitment, period										2 years
Purchase commitment amount | $														$ 0	$ 0	$ 1,300
Agreement entry date										Oct. 31, 2014
Millen Georgia | Minimum | Kaolin And Bauxite | Supplier 7
Long-term Purchase Commitment [Line Items]
Purchase obligation percentage of annual requirements											50.00%
Millen Georgia | Minimum | Kaolin And Bauxite | Supplier 8
Long-term Purchase Commitment [Line Items]
Purchase obligation percentage of annual requirements										50.00%