Stock Compensation Plans (Details) (SOSARs and Stock Options, USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
SOSARs and Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options & SOSARs outstanding at beginning of period, shares	173
Options exercised, Shares	(121)
Options & SOSARs cancelled / forfeited, Shares	0
Options and SOSARs outstanding at end of period, shares	52	173
Vested and expected to vest at beginning of period, Shares	52
Options exercisable at end of period, Shares	52
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Options & SOSARs outstanding at beginning of period, Weighted-Average Exercise Price	$ 15.99
Options exercised, Weighted-Average Exercise Price	$ 13.49
Options & SOSARs cancelled / forfeited, Weighted-Average Exercise Price	$ 0.00
Options and SOSARs outstanding at end of period, Weighted-Average Exercise Price	$ 21.83	$ 15.99
Vested and expected to vest at end of period, Weighted-Average Exercise Price	$ 21.83
Options exercisable at end of period, Weighted-Average Exercise Price	$ 21.83
Options and SOSARs outstanding at end of period, Weighted-Average Remaining Contractual Term	1 month 28 days
Vested and expected to vest at end of period, Weighted Average Remaining Contractual Term	1 month 28 days
Options exercisable at end of period, Weighted-Average Remaining Contractual Term	1 month 28 days
Options and SOSARs outstanding at end of period, Aggregate Intrinsic Value	$ 1,615
Vested and expected to vest at end of period, Aggregate Intrinsic Value	1,615
Options exercisable at end of period, Aggregate Intrinsic Value	1,615
Total intrinsic value of SOSARs exercised	5,193	4,678	1,937
Total fair value of shares vested	$ 0	$ 576	$ 818
Weighted average fair value of options granted	$ 0.00	$ 0.00	$ 0.00