Employee Benefits (Fair Value Measurement Inputs) (Details) (Retirement Plans, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Cash and Cash Equivalents	Dec. 31, 2012 Cash and Cash Equivalents	Dec. 31, 2012 US Treasury Securities	Dec. 31, 2013 Common Collective Trusts		Dec. 31, 2013 Investment Contracts	Dec. 31, 2012 Investment Contracts	Dec. 31, 2012 Common Stock	Dec. 31, 2012 Mututal Funds - Fixed Income	Dec. 31, 2012 Equity Mutual Funds	Dec. 31, 2013 Limited Partnership Interest in Real Estate		Dec. 31, 2012 Limited Partnership Interest in Real Estate		Dec. 31, 2011 Limited Partnership Interest in Real Estate	Dec. 31, 2013 Fair Value, Inputs, Level 1	Dec. 31, 2012 Fair Value, Inputs, Level 1	Dec. 31, 2013 Fair Value, Inputs, Level 1 Cash and Cash Equivalents	Dec. 31, 2012 Fair Value, Inputs, Level 1 Cash and Cash Equivalents	Dec. 31, 2012 Fair Value, Inputs, Level 1 US Treasury Securities	Dec. 31, 2013 Fair Value, Inputs, Level 1 Common Collective Trusts		Dec. 31, 2013 Fair Value, Inputs, Level 1 Investment Contracts	Dec. 31, 2012 Fair Value, Inputs, Level 1 Investment Contracts	Dec. 31, 2012 Fair Value, Inputs, Level 1 Common Stock	Dec. 31, 2012 Fair Value, Inputs, Level 1 Mututal Funds - Fixed Income	Dec. 31, 2012 Fair Value, Inputs, Level 1 Equity Mutual Funds	Dec. 31, 2013 Fair Value, Inputs, Level 1 Limited Partnership Interest in Real Estate		Dec. 31, 2012 Fair Value, Inputs, Level 1 Limited Partnership Interest in Real Estate		Dec. 31, 2013 Fair Value, Inputs, Level 2	Dec. 31, 2012 Fair Value, Inputs, Level 2	Dec. 31, 2013 Fair Value, Inputs, Level 2 Cash and Cash Equivalents	Dec. 31, 2012 Fair Value, Inputs, Level 2 Cash and Cash Equivalents	Dec. 31, 2012 Fair Value, Inputs, Level 2 US Treasury Securities	Dec. 31, 2013 Fair Value, Inputs, Level 2 Common Collective Trusts		Dec. 31, 2013 Fair Value, Inputs, Level 2 Investment Contracts	Dec. 31, 2012 Fair Value, Inputs, Level 2 Investment Contracts	Dec. 31, 2012 Fair Value, Inputs, Level 2 Common Stock	Dec. 31, 2012 Fair Value, Inputs, Level 2 Mututal Funds - Fixed Income	Dec. 31, 2012 Fair Value, Inputs, Level 2 Equity Mutual Funds	Dec. 31, 2013 Fair Value, Inputs, Level 2 Limited Partnership Interest in Real Estate		Dec. 31, 2012 Fair Value, Inputs, Level 2 Limited Partnership Interest in Real Estate		Dec. 31, 2013 Fair Value, Inputs, Level 3	Dec. 31, 2012 Fair Value, Inputs, Level 3	Dec. 31, 2013 Fair Value, Inputs, Level 3 Cash and Cash Equivalents	Dec. 31, 2012 Fair Value, Inputs, Level 3 Cash and Cash Equivalents	Dec. 31, 2012 Fair Value, Inputs, Level 3 US Treasury Securities	Dec. 31, 2013 Fair Value, Inputs, Level 3 Common Collective Trusts		Dec. 31, 2013 Fair Value, Inputs, Level 3 Investment Contracts	Dec. 31, 2012 Fair Value, Inputs, Level 3 Investment Contracts	Dec. 31, 2012 Fair Value, Inputs, Level 3 Common Stock	Dec. 31, 2012 Fair Value, Inputs, Level 3 Mututal Funds - Fixed Income	Dec. 31, 2012 Fair Value, Inputs, Level 3 Equity Mutual Funds	Dec. 31, 2013 Fair Value, Inputs, Level 3 Limited Partnership Interest in Real Estate		Dec. 31, 2012 Fair Value, Inputs, Level 3 Limited Partnership Interest in Real Estate		Dec. 31, 2013 Common Collective Trusts Equity Funds		Dec. 31, 2013 Common Collective Trusts Fixed Income Funds		Dec. 31, 2013 Common Collective Trusts Fair Value, Inputs, Level 1 Equity Funds		Dec. 31, 2013 Common Collective Trusts Fair Value, Inputs, Level 1 Fixed Income Funds		Dec. 31, 2013 Common Collective Trusts Fair Value, Inputs, Level 2 Equity Funds		Dec. 31, 2013 Common Collective Trusts Fair Value, Inputs, Level 2 Fixed Income Funds		Dec. 31, 2013 Common Collective Trusts Fair Value, Inputs, Level 3 Equity Funds		Dec. 31, 2013 Common Collective Trusts Fair Value, Inputs, Level 3 Fixed Income Funds
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets at end of year	$ 257,831,000	$ 220,568,000	$ 940,000	$ 9,163,000	$ 24,854,000	$ 246,908,000	[1]	$ 1,126,000	$ 1,059,000	$ 52,149,000	$ 59,150,000	$ 65,634,000	$ 8,857,000	[2]	$ 8,559,000	[2]	$ 8,511,000	$ 940,000	$ 210,950,000	$ 940,000	$ 9,163,000	$ 24,854,000	$ 0	[1]	$ 0	$ 0	$ 52,149,000	$ 59,150,000	$ 65,634,000	$ 0	[2]	$ 0	[2]	$ 248,034,000	$ 1,059,000	$ 0	$ 0	$ 0	$ 246,908,000	[1]	$ 1,126,000	$ 1,059,000	$ 0	$ 0	$ 0	$ 0	[2]	$ 0	[2]	$ 8,857,000	$ 8,559,000	$ 0	$ 0	$ 0	$ 0	[1]	$ 0	$ 0	$ 0	$ 0	$ 0	$ 8,857,000	[2]	$ 8,559,000	[2]	$ 142,960,000	[1]	$ 103,948,000	[1]	$ 0	[1]	$ 0	[1]	$ 142,960,000	[1]	$ 103,948,000	[1]	$ 0	[1]	$ 0	[1]
Restriction Period To Sell Partnership Interest Minimum	5 years
Restriction Period To Sell Partnership Interest Maximum	7 years
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, Sales, Issuances, Settlements	$ 0	$ 0

[1] The Common Collective Trusts are invested in equity or fixed income securities, or a combination thereof. The investment objective of each trust is to produce returns in excess of, or commensurate with, its predefined index.

[2] This investment is a commercial real estate partnership that purchases land, develops limited infrastructure, and sells it for commercial development. The Company is restricted from selling its partnership interest during the life of the partnership which is generally 5-7 years. Return on investment is realized as land is sold. The fair value of the limited partnership interest in real estate is based on the NAV of the partnership which reflects the appraised value of the land.