Employee Benefits (Tables)

12 Months Ended

Dec. 31, 2014

Compensation and Retirement Disclosure [Abstract]

Schedule of multiemployer plans

The following table presents the Company's participation in these plans:

	Pension Plan	Pension Protection Act ("PPA")		FIP/RP								Expiration
Pension Trust	Employer	Certified Zone Status (1)		Status	Contributions						Surcharge	of Collective
Fund	Identification Number	2014	2013	P/I (2)	2014		2013		2012		Imposed	Bargaining Agreement
International Union of Operating Engineers-Employers Construction Industry Retirement Plan	91-6028571	Green	Green	N/A	$	1,295	$	534	$	486	—	2015
Associated General Contractors of Washington Carpenter, Piledrivers, and Millwrights	91-6029051	Green	Green	N/A	$	737	$	438	$	400	—	2015
Alaska Carpenters Trust Fund	92-0120866	Green	Green	N/A	$	1,044	$	856	$	142	—	2017
Alaska Laborers Trust Fund	91-6028298	Orange	Orange	P	$	246	$	52	$	—	—	2015

1.    The most recent PPA zone status available in 2014 and 2013 is for the plan's year end during 2013 and 2012, respectively. Zone status is based on information received from the plan and is indicative of the plans funding status. Among other factors, plans in the red zone are generally less than 65 percent funded, plans in the orange zone are less than 80 percent funded and have an Accumulated Funding Deficiency in the current year or projected into the next six years, plans in the yellow zone are less than 80 percent funded, and plans in the green zone are at least 80 percent funded.

2.    The FIP/RP Status P/I column indicates plans for which a financial improvement plan ("FIP") or a rehabilitation plan ("RP") is either pending ("P"), or implemented ("I").