Share Based Compensation, 401(k) Plan and Deferred Compensation - Restricted Performance Share Units (Details) - Restricted Performance Share Units Plan [Member] - Executive Officer [Member] - USD ($) $ in Thousands					12 Months Ended
	Feb. 22, 2016	Feb. 23, 2015	Mar. 12, 2014	Mar. 11, 2014	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2016, shares					364,267
Granted, shares					231,388
Units Cancelled					(62,527)
Non-vested at December 31, 2016, shares					533,128
Units Granted	231,388	186,395	61,720	134,284
Fair Value of Units on Grant Date (in thousands)	$ 3,558	$ 3,933	$ 1,255	$ 2,624
March 11, 2014 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2016, shares					123,155
Granted, shares					0
Units Cancelled					(30,724)
Non-vested at December 31, 2016, shares					92,431
Measurement Period Commencement Date					Jan. 01, 2014
Measurement Period End Date					Dec. 31, 2016
March 12, 2014 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2016, shares					61,720
Granted, shares					0
Units Cancelled					0
Non-vested at December 31, 2016, shares					61,720
Measurement Period Commencement Date					Jan. 01, 2014
Measurement Period End Date					Dec. 31, 2016
February 23, 2015 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2016, shares					179,392
Granted, shares					0
Units Cancelled					(31,803)
Non-vested at December 31, 2016, shares					147,589
Measurement Period Commencement Date					Jan. 01, 2015
Measurement Period End Date					Dec. 31, 2017
February 22, 2016 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2016, shares					0
Granted, shares					231,388
Units Cancelled					0
Non-vested at December 31, 2016, shares					231,388
Measurement Period Commencement Date					Jan. 01, 2016
Measurement Period End Date					Dec. 31, 2018