Employee Benefit Plans (Tables) - Summit Materials, LLC [Member]

12 Months Ended

Jan. 02, 2016

Obligations and Funded Status—The following information is as of December 31, 2015 and December 27, 2014 and for the years ended December 31, 2015, December 27, 2014 and December 28, 2013:


	2015						2014
	Pension benefits			Healthcare & Life Ins.			Pension benefits			Healthcare & Life Ins.
Change in benefit obligations:
Beginning of period	$	28,909		$	13,356		$	25,644		$	14,155
Service cost		159			149			75			106
Interest cost		1,041			447			1,081			493
Actuarial (gain) loss		(1,465	)		(1,720	)		3,798			1,992
Change in plan provision		908			1,896			—			(2,553	)
Benefits paid		(1,638	)		(670	)		(1,689	)		(837	)

End of period		27,914			13,458			28,909			13,356


Change in fair value of plan assets:
Beginning of period	$	18,872		$	—		$	19,074		$	—
Actual return on plan assets		(63	)					526			—
Employer contributions		1,166			670			961			837
Benefits paid		(1,639	)		(670	)		(1,689	)		(837	)

End of period		18,336			—			18,872			—

Funded status of plans	$	(9,578	)	$	(13,458	)	$	(10,037	)	$	(13,356	)


Current liabilities	$	—		$	(964	)	$	—		$	(1,041	)
Noncurrent liabilities		(9,578	)		(12,494	)		(10,037	)		(12,315	)

Liability recognized	$	(9,578	)	$	(13,458	)	$	(10,037	)	$	(13,356	)


Amounts recognized in accumulated other comprehensive income:
Net actuarial loss	$	9,024		$	3,949		$	9,365		$	5,904
Prior service cost		—			(2,206	)		—			(2,380	)

Total amount recognized	$	9,024		$	1,743		$	9,365		$	3,524

Components of Net Periodic Benefit Cost

Components of net periodic benefit cost:
Service cost	$	159		$	149		$	75		$	106		$	295		$	236
Interest cost		1,041			447			1,081			493			963			513
Amortization of loss		326			235			117			227			387			314
Expected return on plan assets		(1,385	)		—			(1,378	)		—			(1,348	)		—
Curtailments		—			—			—			(1,346	)		—			—
Special termination benefits		—			—			—			—			—			39
Amortization of prior service credit		—			(174	)		—			(174	)		—			(180	)

Net periodic benefit cost	$	141		$	657		$	(105	)	$	(694	)	$	297		$	922

Amounts Recognized in Other Comprehensive (Gain) Loss

	2015						2014						2013
	Pension benefits			Healthcare & Life Ins.			Pension benefits			Healthcare & Life Ins.			Pension benefits			Healthcare & Life Ins.
Amounts recognized in other comprehensive (income) loss:
Net actuarial (loss) gain	$	(16	)	$	(1,720	)	$	4,650		$	1,992		$	(2,838	)	$	(1,048	)
Prior service cost		—			—			—			(2,553	)		—			—
Amortization of prior year service cost		—			174			—			174			—			180
Curtailment benefit		—			—			—			1,346			—			—
Amortization of gain		(326	)		(235	)		(117	)		(227	)		(387	)		(314	)
Adjustment to Prior Service Cost due to purchase accounting		—			—			—			—			—			—

Total amount recognized	$	(342	)	$	(1,781	)	$	4,533		$	732		$	(3,225	)	$	(1,182

Weighted-Average Assumptions Used to Determine Benefit Obligations

Assumptions—Weighted-average assumptions used to determine the benefit obligations as of year-end 2015 and 2014 are:


	2015		2014
	Pension benefits	Healthcare & Life Ins.	Pension benefits	Healthcare & Life Ins.
Discount rate	3.74% - 3.97%	3.34% - 3.80%	3.50% - 3.65%	3.52%
Expected long-term rate of return on plan assets	7.30%	N/A	7.30%	N/A

Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost

Weighted-average assumptions used to determine net periodic benefit cost for years ended January 2, 2016, December 27, 2014 and December 28, 2013:

2015

2014

2013

Pension

Healthcare

Pension

Healthcare

Pension

Healthcare

benefits

& Life Ins.

benefits

& Life Ins.

benefits

& Life Ins.

Discount rate

3.50% - 3.98%

3.52%

4.21% - 4.46%

4.33%

3.30% - 3.57%

3.41%

Expected long-term rate of return on plan assets

7.30%

N/A

7.50%

N/A

7.50%

N/A

Effects of One Percentage-Point Change in Assumed Health Care Cost Trend Rates

A one percentage-point change in assumed health care cost trend rates would have the following effects as of year-end 2015 and 2014:


	2015					2014
	Increase		Decrease			Increase		Decrease
Total service cost and interest cost components	$	45	$	(36	)	$	39	$	(34	)
APBO		1,302		(1,121	)		1,333		(1,136	)

Fair Value of Company's Pension Plans' Assets

The fair value of the Plans’ assets by asset class and fair value hierarchy level as of December 31, 2015 and December 27, 2014 are as follows:


	2015
			Quoted prices in active
	Total fair		markets for identical		Observable
	value		assets (Level 1)		inputs (Level 2)
Fixed income securities:
Intermediate - government	$	1,410	$	—	$	1,410
Intermediate - corporate		3,376		—		3,376
Short-term - government		390		—		390
Short-term - corporate		5,571		—		5,571
Equity securities:
U.S. Large cap value		1,148		1,148		—
U.S. Large cap growth		1,153		1,153		—
U.S. Mid cap value		557		557		—
U.S. Mid cap growth		569		569		—
U.S. Small cap value		554		554		—
U.S. Small cap growth		554		554		—
International		1,118		1,118		—
Cash		1,592		1,592		—
Precious metals		345		345		—

Total	$	18,337	$	7,590	$	10,747


	2014
			Quoted prices in active
	Total fair		markets for identical		Observable
	value		assets (Level 1)		inputs (Level 2)
Fixed income securities:
Intermediate - government	$	1,468	$	—	$	1,468
Intermediate - corporate		3,342		—		3,342
Short-term - government		2,435		—		2,435
Short-term - corporate		3,700		—		3,700
Equity securities:
U.S. Large cap value		1,180		1,180		—
U.S. Large cap growth		1,173		1,173		—
U.S. Mid cap value		590		590		—
U.S. Mid cap growth		598		598		—
U.S. Small cap value		597		597		—
U.S. Small cap growth		611		611		—
International		1,098		1,098		—
Cash		1,712		1,712		—
Precious metals		368		368		—

Total	$	18,872	$	7,927	$	10,945

Estimated Benefit Payments

The estimated benefit payments for each of the next five years and the five-year period thereafter are as follows:


	Pension		Healthcare and Life
	benefits		Insurance Benefits
2016		1,768		964
2017		1,768		913
2018		1,807		941
2019		1,812		918
2020		1,788		937
2021- 2024		8,680		4,598

Total	$	17,623	$	9,271