Retirement Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Net settlement loss	$ 2,400		$ 1,900
Minimum time period for expected rate of return	10 years
Maximum time period for expected rate of return	20 years
Accrued cost related to retirement plans included in other long term liabilities	$ 36,900	$ 35,100
Change in equity as a result of change in deferred net loss	100	(16,100)	14,700
Change in equity as result of change in deferred net loss taxes	$ (100)	2,600	7,100
Reit Conversion Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Net settlement loss			700
Corporate Operating Expenses [Member]
Defined Benefit Plan Disclosure [Line Items]
Net settlement loss			1,200
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of qualified earnings credited to the account of the participant of benefit plan	3.00%
Retirement age benefit payable to a terminated vested participant upon retirement	65 years
Retirement age for benefit payments, earliest age allowed contingent of minimum service requirement	55 years
Number of years of service at the time plan was frozen for the eligibility of benefit payable to terminated vested participant at age 55	15 years
Net settlement loss	$ 2,356		$ 1,878
Expected contribution to defined benefit plan	0
Net (gain) loss recognized in other comprehensive income	(200)	18,700
Unrecognized actuarial losses included in other comprehensive loss, net of tax	31,700	31,800
Unrecognized actuarial losses included in other comprehensive loss	44,200	$ 44,400
Defined benefit plan amounts that will be amortized from accumulated other comprehensive income loss in next fiscal year	1,200
Non Qualified Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for defined benefit plan	$ 15,100