Derivatives (Interest Rate Swap) (Details) - USD ($) $ in Thousands			12 Months Ended
	May 13, 2014	Jul. 02, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	May 09, 2014	Mar. 31, 2014
Interest Rate Agreements
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount de-designated, percent of total		10.00%
Gain (loss) on derivative instruments					$ (687)
Interest Rate Agreements | Loss on Redemption of Debt
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments					(757)
Interest Rate Agreements | Other Income (Expense)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments					70
Senior Notes | Interest Rate Agreements
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount de-designated		$ 4,500
Cash Flow Hedging | Interest Rate Swap - Fixed
Derivative Instruments, Gain (Loss) [Line Items]
Cash flow hedge loss to be reclassified within 12 months			$ 1,900
Cash Flow Hedging | Interest Rate Swap - Fixed | Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative reclassified from accumulated OCI into income			(2,399)	$ 0
Cash Flow Hedging | Senior Loans | Interest Rate Swap - Fixed
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount			$ 220,000
Derivative, Fixed Interest Rate			4.85%
Cash Flow Hedging | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain (loss) recognized in other comprehensive income (loss)			$ 721	(1,909)	(1,392)
Effective portion of derivative reclassified from accumulated OCI into income			(1,129)	(2,131)	573
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Swap - Fixed
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion of derivative gain (loss) recognized in other comprehensive income (loss)			$ (2,056)	$ (2,378)
Fair Value Hedging | Senior Notes | Interest Rate Agreements
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount						$ 45,000
Derivative,cash paid on settlement of hedge	$ 1,100
Fair Value Hedging | Senior Notes | Interest Rate Agreements | Loss on Redemption of Debt
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments					$ (800)
Fair Value Hedging | Designated as Hedging Instrument | Senior Notes | Interest Rate Agreements
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount							$ 40,500