Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Summary of Provision for Income Tax Expense (Benefit)

The provision for income tax expense (benefit) consisted of the following:

	(In thousands) Years Ended December 31,
	2016		2015			2014
Current tax expense (benefit)
Federal	$	5,953	$	(1,511	)	$	5,258
State	2,982		(418		)	244
	8,935		(1,929		)	5,502
Deferred tax expense (benefit)
Federal	3,876		(28,011		)	1,186
State	41		(1,771		)	(315		)
	3,917		(29,782		)	871
Income tax expense (benefit)	$	12,852	$	(31,711	)	$	6,373

Summary of Deferred Tax Assets (Liabilities)

Deferred tax (liabilities) assets were comprised of the following:

	(In thousands) December 31,
	2016			2015
Deferred tax assets:
Accrued expenses	$	760		$	1,363
Allowance for doubtful accounts	184			134
Contract overrun reserves	1,776			4,412
Deferred compensation	507			491
Employment-related accruals	2,888			2,463
Environmental reserves	769			772
Federal tax credit carryforwards	4,234			7,031
Inventory reserves	2,313			2,703
Investment in common stock	—			297
Pension obligation	4,002			3,299
State net operating loss carryforwards	63			1,402
State tax credit carryforwards	6,585			5,937
Stock-based compensation	1,950			2,165
Workers’ compensation	122			133
Other	2,098			1,595
Total gross deferred tax assets	28,251			34,197
Valuation allowance	(6,607		)	(7,477		)
Total gross deferred tax assets, net of valuation allowance	21,644			26,720
Deferred tax liabilities:
Depreciation	(13,167		)	(11,802		)
Goodwill	(3,909		)	(3,632		)
Intangibles	(35,071		)	(37,891		)
Prepaid insurance	(626		)	(514		)
Section 481(a) adjustment	—			(682		)
Unbilled receivables	(2		)	—
Total gross deferred tax liabilities	(52,775		)	(54,521		)
Net deferred tax liabilities	$	(31,131	)	$	(27,801	)

Principle Reasons for Variation Between Expected and Effective Tax Rate

The principal reasons for the variation between the statutory and effective tax rates were as follows:

	Years Ended December 31,
	2016	2015	2014
Statutory federal income tax (benefit) rate	35.0%	(35.0)%	35.0%
State income taxes (net of federal benefit)	5.7	(1.2)	0.9
Qualified domestic production activities	(2.0)	0.5	(2.3)
Research and development tax credits	(8.6)	(2.9)	(11.3)
Goodwill impairment	—	8.1	—
Changes in valuation allowance	0.9	0.6	8.5
Non-deductible book expenses	0.2	0.2	0.9
Changes in deferred tax assets	1.5	0.1	(5.0)
Remeasurement of deferred taxes for changes in state tax law	—	—	(1.9)
Changes in tax reserves	—	0.1	(0.7)
Other	1.0	(0.2)	0.2
Effective income tax (benefit) rate	33.7%	(29.7)%	24.3%

Reconciliation of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits was as follows:

	(In thousands) Years Ended December 31,
	2016			2015			2014
Balance at January 1,	$	2,963		$	2,803		$	2,297
Additions for tax positions related to the current year	476			702			668
Additions for tax positions related to prior years	385			—			31
Reductions for tax positions related to prior years	(567		)	(48		)	(22		)
Reductions for lapse of statute of limitations	(221		)	(494		)	(171		)
Balance at December 31,	$	3,036		$	2,963		$	2,803