Restructuring Expense - Fan Pier Restructuring Liability (Details) ft² in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) ft²	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) ft²	Dec. 31, 2013 USD ($)
Restructuring activities
Restructuring expenses	$ 1,524	$ 1,826	$ 2,128	$ (3,272)	$ 4,164	$ 40,843	$ (270)	$ 6,188	$ 2,206	$ 50,925	$ 40,521
Fan Pier Move Restructuring
Restructuring Cost and Reserve [Line Items]
Discount rate, lease restructuring liability (percent)						9.00%
Area of real estate property (in square feet) | ft²					120					120
Restructuring activities
Liability, beginning of the period				$ 33,390				$ 797	33,390	$ 797	0
Cash payments									(30,022)	(18,271)	(401)
Cash received from subleases									4,229	0	0
Restructuring expenses									(1,633)	50,864	1,198
Liability, end of the period	$ 5,964				$ 33,390				$ 5,964	$ 33,390	$ 797