Fair Value Measurements--Nonrecurring Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Nonrecurring Fair Value Measurements [Line Items]
Liabilities incurred in current period	$ 139	$ 76
Significant unobservable inputs (Level 3) \| Nonrecurring fair value measurements
Nonrecurring Fair Value Measurements [Line Items]
Annual inflation rate	2.95%	2.95%
Credit-adjusted risk-free interest rate	5.80%	6.40%
Liabilities incurred in current period	$ 139	$ 76

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration