Segment Reporting Information (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015		Jun. 30, 2016		Jun. 30, 2015
Segment Reporting Information [Line Items]
Revenues	$ 178,251	$ 217,617		$ 358,543		$ 437,920
Gross Profit	24,331	29,506		50,036		58,580
Depreciation and Amortization Expense	3,998	4,397		8,409		8,874
Selling, General & Administrative Expenses	15,585	17,585		32,376		35,124
Operating Income	8,427	11,588		17,008		22,787
Capital Expenditures	2,951	4,747		5,236		7,665
Other General Expense	495	463	[1]	1,384	[2]	1,142	[3]
Operating Segments
Segment Reporting Information [Line Items]
Revenues	178,251	217,617		358,543		437,920
Corporate/ Other
Segment Reporting Information [Line Items]
Revenues	(2,400)	(2,425)		(4,380)		(6,075)
Gross Profit	(371)	(949)		(795)		(1,911)
Depreciation and Amortization Expense	472	694		1,328		1,431
Selling, General & Administrative Expenses	5,163	5,403		10,968		10,955
Operating Income	(5,534)	(6,352)		(11,762)		(12,867)
Capital Expenditures	380	1,828		573		2,151
Other General Expense	0	0	[1]	688	[2]	0	[3]
Global Truck & Bus
Segment Reporting Information [Line Items]
Revenues	112,126	149,345		228,630		295,251
Global Truck & Bus | Operating Segments
Segment Reporting Information [Line Items]
Revenues	111,883	149,263		228,167		295,068
Gross Profit	14,432	22,885		32,255		44,230
Depreciation and Amortization Expense	2,190	2,214		4,224		4,438
Selling, General & Administrative Expenses	5,642	7,492		12,137		14,438
Operating Income	8,506	15,095		19,535		29,195
Capital Expenditures	1,540	2,058		2,447		3,140
Other General Expense	284	463	[1]	375	[2]	1,142	[3]
Global Truck & Bus | Intersegment Revenues
Segment Reporting Information [Line Items]
Revenues	243	82		463		183
Global Construction & Agriculture
Segment Reporting Information [Line Items]
Revenues	68,525	70,697		134,293		148,744
Global Construction & Agriculture | Operating Segments
Segment Reporting Information [Line Items]
Revenues	66,368	68,354		130,376		142,852
Gross Profit	10,270	7,570		18,576		16,261
Depreciation and Amortization Expense	1,336	1,489		2,857		3,005
Selling, General & Administrative Expenses	4,780	4,690		9,271		9,731
Operating Income	5,455	2,845		9,235		6,459
Capital Expenditures	1,031	861		2,216		2,374
Other General Expense	211	0	[1]	321	[2]	0	[3]
Global Construction & Agriculture | Intersegment Revenues
Segment Reporting Information [Line Items]
Revenues	$ 2,157	$ 2,343		$ 3,917		$ 5,892

[1] Other items include costs associated with plant closures, including employee severance and retention costs, lease cancellation costs, building repairs and costs to transfer equipment.

[2] Other items in the GTB and GCA Segments include costs associated with plant closures, including employee severance and retention costs, lease cancellation costs, building repairs and costs to transfer equipment; and in corporate a write down of an asset held for sale and severance costs.

[3] Other items include costs associated with plant closures, including employee severance and retention costs, lease cancellation costs, building repairs and costs to transfer equipment.