Income Taxes (Tables)

12 Months Ended

Jan. 31, 2018

Income Tax Disclosure [Abstract]

Reconciliation of income tax computed at the federal statutory rate to the company's effective income tax rate

The reconciliation of income tax computed at the federal statutory rate to the Company's effective income tax rate was as follows:

	For the years ended January 31,
	2018		2017		2016
Tax at U.S. federal statutory rate	33.8	%	35.0	%	35.0	%
Impact of the Tax Cuts and Jobs Act	(0.1	)	—		—
State and local income taxes, net of U.S. federal tax benefit	1.6		0.7		(2.8	)
Tax credit for research activities	(1.8	)	(3.7	)	(24.2	)
Tax benefit on qualified production activities	(3.0	)	(2.8	)	(13.7	)
Tax benefit on insurance premiums	(1.3	)	(1.5	)	(10.3	)
Change in uncertain tax positions	0.1		(0.3	)	1.8
Foreign tax rate difference	—		(0.3	)	(2.9	)
Impact of settlement of stock-based awards	1.2		—		—
Other, net	—		0.4		(1.7	)
	30.5	%	27.5	%	(18.8	)%

Significant components of the company's income tax provision

Significant components of the Company's income tax provision were as follows:

	For the years ended January 31,
	2018			2017		2016
Income tax provision:
Currently payable	$	18,754		$	7,354	$	5,272
Deferred expense (benefit)	(787		)	307		(6,039		)
Income tax expense (benefit)	$	17,967		$	7,661	$	(767	)

Significant components of the company's deferred tax assets and liabilities

Significant components of the Company's deferred tax assets and liabilities were as follows:

	As of January 31,
	2018			2017
Deferred tax assets:
Accounts receivable	$	184		$	212
Inventories	664			978
Accrued vacation	647			887
Insurance obligations	137			383
Accrued benefit liabilities	—			41
Warranty obligations	262			565
Postretirement benefits	1,929			3,072
Uncertain tax positions	491			803
Share-based compensation	1,761			3,201
Other accrued liabilities	54			68
	6,129			10,210
Deferred tax (liabilities):
Depreciation and amortization	(6,082		)	(10,565		)
Other	(643		)	(1,048		)
	(6,725		)	(11,613		)
Net deferred tax (liability)	$	(596	)	$	(1,403	)

Summary of the activity related to the gross unrecognized tax benefits (excluding interest and penalties)

A summary of the activity related to the gross unrecognized tax benefits (excluding interest and penalties) is as follows:

	For the years ended January 31,
	2018			2017
Gross unrecognized tax benefits at beginning of year	$	2,110		$	2,327
Increases in tax positions related to the current year	426			279
Decreases in tax positions related to prior years	—			(193		)
Decreases as a result of lapses in applicable statutes of limitation	(320		)	(303		)
Gross unrecognized tax benefits at end of year	$	2,216		$	2,110