Employee Benefit Plans Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended					12 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Pension Plan, Defined Benefit [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member]	Dec. 31, 2011 Pension Plan, Defined Benefit [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Fair Value, Level 2 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Equity Securities, Domestic [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Equity Securities, Domestic [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Equity Securities, Domestic [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Equity Securities, Domestic [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Equity Securities, Domestic [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Equity Securities, Domestic [Member] Fair Value, Level 2 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Equity Securities, International [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Equity Securities, International [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Equity Securities, International [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Equity Securities, International [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Equity Securities, International [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Equity Securities, International [Member] Fair Value, Level 2 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Domestic Debt Securities [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Domestic Debt Securities [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Domestic Debt Securities [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Domestic Debt Securities [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Domestic Debt Securities [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Domestic Debt Securities [Member] Fair Value, Level 2 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Foreign Debt Securities [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Foreign Debt Securities [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Foreign Debt Securities [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Foreign Debt Securities [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Foreign Debt Securities [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Foreign Debt Securities [Member] Fair Value, Level 2 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Real Estate Funds [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Real Estate Funds [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Real Estate Funds [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Real Estate Funds [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Real Estate Funds [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Real Estate Funds [Member] Fair Value, Level 2 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Short-term Investments [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Short-term Investments [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Short-term Investments [Member] Fair Value, Level 1 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Short-term Investments [Member] Fair Value, Level 1 [Member]	Dec. 31, 2013 Pension Plan, Defined Benefit [Member] Short-term Investments [Member] Fair Value, Level 2 [Member]	Dec. 31, 2012 Pension Plan, Defined Benefit [Member] Short-term Investments [Member] Fair Value, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value			$ 341,905	$ 320,699	$ 295,655	$ 110,676	$ 128,393	$ 231,229	$ 192,306	$ 139,694	$ 126,904	$ 29,293	$ 50,653	$ 110,401	$ 76,251	$ 87,039	$ 78,931	$ 55,692	$ 51,758	$ 31,347	$ 27,173	$ 85,222	$ 81,045	$ 0	$ 0	$ 85,222	$ 81,045	$ 15,134	$ 15,745	$ 15,134	$ 15,745	$ 0	$ 0	$ 9,678	$ 10,208	$ 9,678	$ 10,208	$ 0	$ 0	$ 5,138	$ 7,866	$ 879	$ 29	$ 4,259	$ 7,837
Valuation Methodology						Level 1 — Net asset value in an observable market.		Level 2 — Assets classified as level two are held in collective trust funds. The net asset value of a collective trust is calculated by determining the fair value of the fund’s underlying assets, deducting its liabilities, and dividing by the units outstanding as of the valuation date. These funds are not publicly traded; however, the unit price calculation is based on observable market inputs of the funds’ underlying assets.
Changes in Valuation Methodology	no changes in the methodology	no changes in the methodology