Income Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Blanket purchase agreement, amount	$ 600,000,000
Limitation on use, amount	4,900,000
Excess tax benefit from exercise of stock options	1,550,000
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards	15,900,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards	$ 13,000,000
Minimum [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards, expiration date	Jan. 01, 2017
Minimum [Member] | State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards, expiration date	Jan. 01, 2020
Maximum [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards, expiration date	Jan. 01, 2033
Maximum [Member] | State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards, expiration date	Jan. 01, 2029