Employee Benefit and Deferred Compensation Plans (Details 5) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	$ 36,892	$ 26,532
Cash and cash equivalents
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	13,927	1,882
U.S. large cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	9,277	9,144
U.S. mid cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	5,085	5,210
U.S. small cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	1,516	2,791
International companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	1,505	1,489
Investments in registered investment companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	848	898
U.S. government bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	1,883	2,003
Corporate bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	2,750	3,008
Municipal Obligations [Member]
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	101	107
Quoted Prices In Active Markets for Identical Assets (Level 1)
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	32,158	21,414
Quoted Prices In Active Markets for Identical Assets (Level 1) | Cash and cash equivalents
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	13,927	1,882
Quoted Prices In Active Markets for Identical Assets (Level 1) | U.S. large cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	9,277	9,144
Quoted Prices In Active Markets for Identical Assets (Level 1) | U.S. mid cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	5,085	5,210
Quoted Prices In Active Markets for Identical Assets (Level 1) | U.S. small cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	1,516	2,791
Quoted Prices In Active Markets for Identical Assets (Level 1) | International companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	1,505	1,489
Quoted Prices In Active Markets for Identical Assets (Level 1) | Investments in registered investment companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	848	898
Quoted Prices In Active Markets for Identical Assets (Level 1) | U.S. government bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Quoted Prices In Active Markets for Identical Assets (Level 1) | Corporate bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Quoted Prices In Active Markets for Identical Assets (Level 1) | Municipal Obligations [Member]
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2)
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	4,734	5,118
Significant Other Observable Inputs (Level 2) | Cash and cash equivalents
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2) | U.S. large cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2) | U.S. mid cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2) | U.S. small cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2) | International companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2) | Investments in registered investment companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Other Observable Inputs (Level 2) | U.S. government bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	1,883	2,003
Significant Other Observable Inputs (Level 2) | Corporate bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	2,750	3,008
Significant Other Observable Inputs (Level 2) | Municipal Obligations [Member]
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	101	107
Significant Unobservable Inputs (Level 3)
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | Cash and cash equivalents
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | U.S. large cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | U.S. mid cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | U.S. small cap companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | International companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | Investments in registered investment companies
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | U.S. government bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | Corporate bonds
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	0	0
Significant Unobservable Inputs (Level 3) | Municipal Obligations [Member]
Fair values of defined benefit pension plan assets by category of the firm
Fixed income securities	$ 0	$ 0