Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent		50.00%
Employers matching contribution, annual vesting percentage		20.00%
Employers matching contribution, vesting term (in years)		5 years
Defined benefit plan, cost of employer contribution		$ 1,509	$ 2,886	$ 3,269
Change in projected benefit obligation		1,200
Projected change in 2015 pension expense		100
Special charges		2,092	1,996
Fair value of plan assets	$ 31,776	31,776	39,369	39,826
Defined benefit plan, settlement charge	$ 4,500	4,457	0	$ 0
Defined Benefit Plan, Other Costs		$ (8,800)	$ 0
Barclays Capital Aggregate Bond Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Composite benchmark index markup		25.00%
Morgan Stanley Capital International EAFE Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Composite benchmark index markup		8.00%
Russell 1000 Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Composite benchmark index markup		47.00%
Russell 2000 Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Composite benchmark index markup		10.00%
Russell 600 Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Composite benchmark index markup		8.00%
Qualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash contributions to defined benefit pension plan		$ 1,000
Expected voluntary cash contributions for next year		1,600
Nonqualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash contributions to defined benefit pension plan		400
Expected voluntary cash contributions for next year		$ 400
Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Long-term target allocations for plan assets in equities		73.00%
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Long-term target allocations for plan assets in equities		25.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Composite benchmark index markup		2.00%
Long-term target allocations for plan assets in equities		2.00%
401K [Member] | United States Postretirement Benefit Plan of US Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of employees' gross pay		5.00%